Ann M. Arvin
Lucile Salter Packard Professor of Pediatrics and Professor of Microbiology and Immunology, Emerita
Pediatrics - Infectious Diseases
Academic Appointments
-
Emeritus Faculty, Acad Council, Pediatrics - Infectious Diseases
-
Member, Bio-X
-
Member, Stanford Cancer Institute
-
Member, Wu Tsai Neurosciences Institute
Administrative Appointments
-
Associate Dean of Research, Stanford University (2001 - 2006)
-
Vice Provost and Dean of Research, Stanford University (2006 - 2018)
Honors & Awards
-
E. Mead Johnson Award, Society for Pediatric Research (1992)
-
John F. Enders Award, Infectious Diseases Society of America (2002)
-
Elected member, Association of American Physicians (2002)
-
Elected member, Institute of Medicine of the National Academy of Science (2003)
-
Albion Walter Hewlett Award, Stanford University School of Medicine (2004)
-
Director's Advisory Council, National Institute of Allergy and Infectious Diseases (2007-2011)
-
Elected member, American Association for the Advancement of Science (2009)
-
Distinguished Graduate Award, University of Pennsylvania School of Medicine (2010)
-
Elected Member, American Academy of Arts and Sciences (2012)
Professional Education
-
M.D., University of Pennsylvania School of Medicine, Medicine (1972)
Current Research and Scholarly Interests
Varicella-zoster virus (VZV) causes varicella (chickenpox) and zoster (shingles). Our laboratory investigates the molecular virology of VZV, focusing on the functional roles of particular viral gene products in pathogenesis and virus-cell interactions in differentiated human cells in SCID mouse models of VZV infection in vivo. Aspects of VZV tropism are investigated using SCID mice that have human skin, T cell and dorsal root ganglion xenografts and VZV recombinant viruses that have targeted mutations of viral promoters, open reading frames and non-coding regions. The consequences of targeted mutations in the VZV genome reveal functions that are important for VZV pathogenesis and that counteract intrinsic cellular regulation of VZV replication. These studies provide information relevant for developing new genetically engineered vaccines to reduce the disease burden of VZV infections.
2023-24 Courses
-
Independent Studies (14)
- Directed Reading in Immunology
IMMUNOL 299 (Aut, Sum) - Directed Reading in Microbiology and Immunology
MI 299 (Win, Spr) - Directed Reading in Pediatrics
PEDS 299 (Aut, Win, Spr, Sum) - Early Clinical Experience
PEDS 280 (Aut, Win, Spr, Sum) - Early Clinical Experience in Immunology
IMMUNOL 280 (Aut, Sum) - Graduate Research
IMMUNOL 399 (Sum) - Graduate Research
MI 399 (Win, Spr) - Graduate Research
PEDS 399 (Aut, Win, Spr, Sum) - Medical Scholars Research
MI 370 (Win, Spr) - Medical Scholars Research
PEDS 370 (Aut, Win, Spr, Sum) - Teaching in Immunology
IMMUNOL 290 (Aut, Sum) - Undergraduate Directed Reading/Research
PEDS 199 (Aut, Win, Spr, Sum) - Undergraduate Research
IMMUNOL 199 (Aut, Sum) - Undergraduate Research
MI 199 (Win, Spr)
- Directed Reading in Immunology
Graduate and Fellowship Programs
All Publications
-
Targeted mutagenesis of the herpesvirus fusogen central helix captures transition states.
Nature communications
2023; 14 (1): 7958
Abstract
Herpesviruses remain a burden for animal and human health, including the medically important varicella-zoster virus (VZV). Membrane fusion mediated by conserved core glycoproteins, the fusogen gB and the heterodimer gH-gL, enables herpesvirus cell entry. The ectodomain of gB orthologs has five domains and is proposed to transition from a prefusion to postfusion conformation but the functional relevance of the domains for this transition remains poorly defined. Here we describe structure-function studies of the VZV gB DIII central helix targeting residues 526EHV528. Critically, a H527P mutation captures gB in a prefusion conformation as determined by cryo-EM, a loss of membrane fusion in a virus free assay, and failure of recombinant VZV to spread in cell monolayers. Importantly, two predominant cryo-EM structures of gB[H527P] are identified by 3D classification and focused refinement, suggesting they represented gB conformations in transition. These studies reveal gB DIII as a critical element for herpesvirus gB fusion function.
View details for DOI 10.1038/s41467-023-43011-w
View details for PubMedID 38042814
View details for PubMedCentralID PMC10693595
-
Creating the "Dew Drop on a Rose Petal": the Molecular Pathogenesis of Varicella-Zoster Virus Skin Lesions.
Microbiology and molecular biology reviews : MMBR
2023: e0011622
Abstract
Varicella-zoster virus (VZV) is a human alphaherpesvirus that causes varicella (chicken pox) as the primary infection in a susceptible host. Varicella is very contagious through its transmission by direct contact with vesicular skin lesions that contain high titers of infectious virus and respiratory droplets. While the clinical manifestations of primary VZV infection are well recognized, defining the molecular mechanisms that drive VZV pathogenesis in the naive host before adaptive antiviral immunity is induced has been a challenge due to species specificity. This review focuses on advances made in identifying the differentiated human host cells targeted by VZV to cause varicella, the processes involved in viral takeover of these heterogenous cell types, and the host cell countermeasures that typically culminate in a benign illness. This work has revealed many unexpected and multifaceted mechanisms used by VZV to achieve its high prevalence and persistence in the human population.
View details for DOI 10.1128/mmbr.00116-22
View details for PubMedID 37354037
-
Insights From Studies of the Genetics, Pathogenesis, and Immunogenicity of the Varicella Vaccine.
The Journal of infectious diseases
2022; 226 (Supplement_4): S385-S391
Abstract
While the varicella vaccine was created with approaches established for other live attenuated viral vaccines, novel methods to probe virus-host interactions have been used to explore the genetics, pathogenesis, and immunogenicity of the vaccine compared to wild-type varicella-zoster virus (VZV). As summarized here, a mechanism-based understanding of the safety and efficacy of the varicella vaccine has been achieved through these investigations.
View details for DOI 10.1093/infdis/jiac278
View details for PubMedID 36265853
-
Modulation of Host Cell Signaling Pathways by Varicella-Zoster Virus.
Current topics in microbiology and immunology
2022
Abstract
Host-pathogen interactions involve complex inside-out and outside-in signal transmission through critical cellular networks that dictate disease outcomes. The phosphoinositide 3-kinase (PI3K)/Akt pathway is a pivotal junction that regulates several cell functions, and phospho-Akt (pAkt) is often found to be constitutively active in cancer cells, similar to phospho-STAT3. In this chapter, we discuss the regulation of PI3K/Akt pathway in VZV infected cells and of other pathways including p53 which, unlike pAkt and pSTAT3, directs cells towards apoptosis. The fine spatio-temporal balance of activation of pro- and anti-apoptotic factors during VZV infection likely provides an optimum environment for the virus to replicate and cause disease in the human host.
View details for DOI 10.1007/82_2021_251
View details for PubMedID 35624345
-
The N-terminus of varicella-zoster virus glycoprotein B has a functional role in fusion.
PLoS pathogens
2021; 17 (1): e1008961
Abstract
Varicella-zoster virus (VZV) is a medically important alphaherpesvirus that induces fusion of the virion envelope and the cell membrane during entry, and between cells to form polykaryocytes within infected tissues during pathogenesis. All members of the Herpesviridae, including VZV, have a conserved core fusion complex composed of glycoproteins, gB, gH and gL. The ectodomain of the primary fusogen, gB, has five domains, DI-V, of which DI contains the fusion loops needed for fusion function. We recently demonstrated that DIV is critical for fusion initiation, which was revealed by a 2.8Å structure of a VZV neutralizing mAb, 93k, bound to gB and mutagenesis of the gB-93k interface. To further assess the mechanism of mAb 93k neutralization, the binding site of a non-neutralizing mAb to gB, SG2, was compared to mAb 93k using single particle cryogenic electron microscopy (cryo-EM). The gB-SG2 interface partially overlapped with that of gB-93k but, unlike mAb 93k, mAb SG2 did not interact with the gB N-terminus, suggesting a potential role for the gB N-terminus in membrane fusion. The gB ectodomain structure in the absence of antibody was defined at near atomic resolution by single particle cryo-EM (3.9Å) of native full-length gB purified from infected cells and by X-ray crystallography (2.4Å) of the transiently expressed ectodomain. Both structures revealed that the VZV gB N-terminus (aa72-114) was flexible based on the absence of visible structures in the cryo-EM or X-ray crystallography data but the presence of gB N-terminal peptides were confirmed by mass spectrometry. Notably, N-terminal residues 109KSQD112 were predicted to form a small α-helix and alanine substitution of these residues abolished cell-cell fusion in a virus-free assay. Importantly, transferring the 109AAAA112 mutation into the VZV genome significantly impaired viral propagation. These data establish a functional role for the gB N-terminus in membrane fusion broadly relevant to the Herpesviridae.
View details for DOI 10.1371/journal.ppat.1008961
View details for PubMedID 33411789
-
Varicella-zoster virus: molecular controls of cell fusion-dependent pathogenesis.
Biochemical Society transactions
2020
Abstract
Varicella-zoster virus (VZV) is the causative agent of chicken pox (varicella) and shingles (zoster). Although considered benign diseases, both varicella and zoster can cause complications. Zoster is painful and can lead to post herpetic neuralgia. VZV has also been linked to stroke, related to giant cell arteritis in some cases. Vaccines are available but the attenuated vaccine is not recommended in immunocompromised individuals and the efficacy of the glycoprotein E (gE) based subunit vaccine has not been evaluated for the prevention of varicella. A hallmark of VZV pathology is the formation of multinucleated cells termed polykaryocytes in skin lesions. This cell-cell fusion (abbreviated as cell fusion) is mediated by the VZV glycoproteins gB, gH and gL, which constitute the fusion complex of VZV, also needed for virion entry. Expression of gB, gH and gL during VZV infection and trafficking to the cell surface enables cell fusion. Recent evidence supports the concept that cellular processes are required for regulating cell fusion induced by gB/gH-gL. Mutations within the carboxyl domains of either gB or gH have profound effects on fusion regulation and dramatically restrict the ability of VZV to replicate in human skin. This loss of regulation modifies the transcriptome of VZV infected cells. Furthermore, cellular proteins have significant effects on the regulation of gB/gH-gL-mediated cell fusion and the replication of VZV, exemplified by the cellular phosphatase, calcineurin. This review provides the current state-of-the-art knowledge about the molecular controls of cell fusion-dependent pathogenesis caused by VZV.
View details for DOI 10.1042/BST20190511
View details for PubMedID 33259590
-
A glycoprotein B-neutralizing antibody structure at 2.8A uncovers a critical domain for herpesvirus fusion initiation.
Nature communications
2020; 11 (1): 4141
Abstract
Members of the Herpesviridae, including the medically important alphaherpesvirus varicella-zoster virus (VZV), induce fusion of the virion envelope with cell membranes during entry, and between cells to form polykaryocytes in infected tissues. The conserved glycoproteins, gB, gH and gL, are the core functional proteins of the herpesvirus fusion complex. gB serves as the primary fusogen via its fusion loops, but functions for the remaining gB domains remain unexplained. As a pathway for biological discovery of domain function, our approach used structure-based analysis of the viral fusogen together with a neutralizing antibody. We report here a 2.8A cryogenic-electron microscopy structure of native gB recovered from VZV-infected cells, in complex with a human monoclonal antibody, 93k. This high-resolution structure guided targeted mutagenesis at the gB-93k interface, providing compelling evidence that a domain spatially distant from the gB fusion loops is critical for herpesvirus fusion, revealing a potential new target for antiviral therapies.
View details for DOI 10.1038/s41467-020-17911-0
View details for PubMedID 32811830
-
Calcineurin phosphatase activity regulates Varicella-Zoster Virus induced cell-cell fusion.
PLoS pathogens
2020; 16 (11): e1009022
Abstract
Cell-cell fusion (abbreviated as cell fusion) is a characteristic pathology of medically important viruses, including varicella-zoster virus (VZV), the causative agent of chickenpox and shingles. Cell fusion is mediated by a complex of VZV glycoproteins, gB and gH-gL, and must be tightly regulated to enable skin pathogenesis based on studies with gB and gH hyperfusogenic VZV mutants. Although the function of gB and gH-gL in the regulation of cell fusion has been explored, whether host factors are directly involved in this regulation process is unknown. Here, we discovered host factors that modulated VZV gB/gH-gL mediated cell fusion via high-throughput screening of bioactive compounds with known cellular targets. Two structurally related non-antibiotic macrolides, tacrolimus and pimecrolimus, both significantly increased VZV gB/gH-gL mediated cell fusion. These compounds form a drug-protein complex with FKBP1A, which binds to calcineurin and specifically inhibits calcineurin phosphatase activity. Inhibition of calcineurin phosphatase activity also enhanced both herpes simplex virus-1 fusion complex and syncytin-1 mediated cell fusion, indicating a broad role of calcineurin in modulating this process. To characterize the role of calcineurin phosphatase activity in VZV gB/gH-gL mediated fusion, a series of biochemical, biological and infectivity assays was performed. Pimecrolimus-induced, enhanced cell fusion was significantly reduced by shRNA knockdown of FKBP1A, further supporting the role of calcineurin phosphatase activity in fusion regulation. Importantly, inhibition of calcineurin phosphatase activity during VZV infection caused exaggerated syncytia formation and suppressed virus propagation, which was consistent with the previously reported phenotypes of gB and gH hyperfusogenic VZV mutants. Seven host cell proteins that remained uniquely phosphorylated when calcineurin phosphatase activity was inhibited were identified as potential downstream factors involved in fusion regulation. These findings demonstrate that calcineurin is a critical host cell factor pivotal in the regulation of VZV induced cell fusion, which is essential for VZV pathogenesis.
View details for DOI 10.1371/journal.ppat.1009022
View details for PubMedID 33216797
-
The latency-associated transcript locus of herpes simplex virus 1 is a virulence determinant in human skin.
PLoS pathogens
2020; 16 (12): e1009166
Abstract
Herpes simplex virus 1 (HSV-1) infects skin and mucosal epithelial cells and then travels along axons to establish latency in the neurones of sensory ganglia. Although viral gene expression is restricted during latency, the latency-associated transcript (LAT) locus encodes many RNAs, including a 2 kb intron known as the hallmark of HSV-1 latency. Here, we studied HSV-1 infection and the role of the LAT locus in human skin xenografts in vivo and in cultured explants. We sequenced the genomes of our stock of HSV-1 strain 17syn+ and seven derived viruses and found nonsynonymous mutations in many viral proteins that had no impact on skin infection. In contrast, deletions in the LAT locus severely impaired HSV-1 replication and lesion formation in skin. However, skin replication was not affected by impaired intron splicing. Moreover, although the LAT locus has been implicated in regulating gene expression in neurones, we observed only small changes in transcript levels that were unrelated to the growth defect in skin, suggesting that its functions in skin may be different from those in neurones. Thus, although the LAT locus was previously thought to be dispensable for lytic infection, we show that it is a determinant of HSV-1 virulence during lytic infection of human skin.
View details for DOI 10.1371/journal.ppat.1009166
View details for PubMedID 33370402
-
The Use of Single Cell Mass Cytometry to Define the Molecular Mechanisms of Varicella-Zoster Virus Lymphotropism.
Frontiers in microbiology
2020; 11: 1224
Abstract
Unraveling the heterogeneity in biological systems provides the key to understanding of the fundamental dynamics that regulate host pathogen relationships at the single cell level. While most studies have determined virus-host cell interactions using cultured cells in bulk, recent advances in deep protein profiling from single cells enable the understanding of the dynamic response equilibrium of single cells even within the same cell types. Mass cytometry allows the simultaneous detection of multiple proteins in single cells, which helps to evaluate alterations in multiple signaling networks that work in tandem in deciding the response of a cell to the presence of a pathogen or other stimulus. In applying this technique to studying varicella zoster virus (VZV), it was possible to better understand the molecular basis for lymphotropism of the virus and how virus-induced effects on T cells promoted skin tropism. While the ability of VZV to manifest itself in the skin is well established, how the virus is transported to the skin and causes the characteristic VZV skin lesions was not well elucidated. Through mass cytometry analysis of VZV-infected tonsil T cells, we were able to observe that VZV unleashes a "remodeling" program in the infected T cells that not only makes these T cells more skin tropic but also at the same time induces changes that make these T cells unlikely to respond to immune stimulation during the journey to the skin.
View details for DOI 10.3389/fmicb.2020.01224
View details for PubMedID 32676054
-
Distinctive Roles for Type I and Type II Interferons and Interferon Regulatory Factors in the Host Cell Defense against Varicella-zoster Virus.
Journal of virology
2018
Abstract
Both type I and type II interferons (IFNs) have been implicated in the host defense against varicella zoster virus (VZV), a common human herpesvirus that causes varicella and zoster. The purpose of this study was to compare their contributions to the control of VZV replication, to identify the signaling pathways that are critical for mediating their antiviral activity, and to define mechanisms by which the virus counteracts their effects. IFNgamma was much more potent than IFNalpha in blocking VZV infection, which was associated with a differential induction of the interferon regulatory factor (IRF) proteins, IRF1 and IRF9, respectively. These observations account for the clinical experience that while the formation of VZV skin lesions is controlled initially by local immunity, adaptive virus-specific T cell responses are required to prevent life-threatening VZV infections.ImportanceWhile both Type I and Type II IFNs are involved in the control of herpesvirus infections in the human host, to our knowledge, their relative contributions to the restriction of viral replication and spread have not been assessed. We report that IFNgamma has more potent activity than IFNalpha against VZV. Findings from this comparative analysis show that the IFNalpha-IRF9 axis functions as a first line of defense to delay the onset of viral replication and spread whereas the IFNgamma-IRF1 axis has the capacity to block the infectious process. Our findings underscore the importance of IRFs in IFN regulation of herpesvirus infection and account for the clinical experience of initial control of VZV skin infection, attributable to IFNalpha production, together the requirement for induction of adaptive IFNgamma-producing VZV specific T cells to resolve the infection.
View details for PubMedID 30089701
-
The Glycoprotein B Cytoplasmic Domain Lysine Cluster Is Critical for Varicella Zoster Virus Cell-Cell Fusion Regulation and Infection.
Journal of virology
2016
Abstract
The conserved glycoproteins gB and gH-gL are essential for herpesvirus entry and cell-cell fusion induced syncytium formation, a characteristic of varicella-zoster virus (VZV) pathology in skin and sensory ganglia. VZV syncytium formation, which has been implicated in the painful condition of postherpetic neuralgia, is regulated by the cytoplasmic domains of gB (gBcyt) via an immunoreceptor tyrosine-based inhibition motif (ITIM) and gH (gHcyt). A lysine cluster (K894, K897, K898, and K900) in the VZV gBcyt was identified by sequence alignment to be conserved among alphaherpesviruses, suggesting a functional role. Alanine and arginine substitutions were used to determine if the positive charge and susceptibility to posttranslational modifications of these lysines contributed to gB/gH-gL cell-cell fusion. Critically, the positive charge of the lysine residues was necessary for fusion regulation, as alanine substitutions induced a 440% increase in fusion compared to that of the wild-type gBcyt while arginine substitutions had wild-type-like fusion levels in an in vitro gB/gH-gL cell fusion assay. Consistent with these results, the alanine substitutions in the viral genome caused exaggerated syncytium formation, reduced VZV titers (-1.5 log10), and smaller plaques than with the parental Oka (pOka) strain. In contrast, arginine substitutions resulted in syncytia with only 2-fold more nuclei, a -0.5-log10 reduction in titers, and pOka-like plaques. VZV mutants with both an ITIM mutation and either alanine or arginine substitutions had reduced titers and small plaques but differed in syncytium morphology. Thus, effective VZV propagation is dependent on cell-cell fusion regulation by the conserved gBcyt lysine cluster, in addition to the gBcyt ITIM and the gHcyt.Varicella-zoster virus (VZV) is a ubiquitous pathogen that causes chickenpox and shingles. Individuals afflicted with shingles risk developing the painful condition of postherpetic neuralgia (PHN), which has been difficult to treat because the underlying cause is not well understood. Additional therapies are needed, as the current vaccine is not recommended for immunocompromised individuals and its efficacy decreases with the age of the recipient. VZV is known to induce the formation of multinuclear cells in neuronal tissue, which has been proposed to be a factor contributing to PHN. This study examines the role of a lysine cluster in the cytoplasmic domain of the VZV fusion protein, gB, in the formation of VZV induced multinuclear cells and in virus replication kinetics and spread. The findings further elucidate how VZV self-regulates multinuclear cell formation and may provide insight into the development of new PHN therapies.
View details for PubMedID 27795427
-
Neuronal Subtype and Satellite Cell Tropism Are Determinants of Varicella-Zoster Virus Virulence in Human Dorsal Root Ganglia Xenografts In Vivo.
PLoS pathogens
2015; 11 (6)
Abstract
Varicella zoster virus (VZV), a human alphaherpesvirus, causes varicella during primary infection. VZV reactivation from neuronal latency may cause herpes zoster, post herpetic neuralgia (PHN) and other neurologic syndromes. To investigate VZV neuropathogenesis, we developed a model using human dorsal root ganglia (DRG) xenografts in immunodeficient (SCID) mice. The SCID DRG model provides an opportunity to examine characteristics of VZV infection that occur in the context of the specialized architecture of DRG, in which nerve cell bodies are ensheathed by satellite glial cells (SGC) which support neuronal homeostasis. We hypothesized that VZV exhibits neuron-subtype specific tropism and that VZV tropism for SGC contributes to VZV-related ganglionopathy. Based on quantitative analyses of viral and cell protein expression in DRG tissue sections, we demonstrated that, whereas DRG neurons had an immature neuronal phenotype prior to implantation, subtype heterogeneity was observed within 20 weeks and SGC retained the capacity to maintain neuronal homeostasis longterm. Profiling VZV protein expression in DRG neurons showed that VZV enters peripherin+ nociceptive and RT97+ mechanoreceptive neurons by both axonal transport and contiguous spread from SGC, but replication in RT97+ neurons is blocked. Restriction occurs even when the SGC surrounding the neuronal cell body were infected and after entry and ORF61 expression, but before IE62 or IE63 protein expression. Notably, although contiguous VZV spread with loss of SGC support would be predicted to affect survival of both nociceptive and mechanoreceptive neurons, RT97+ neurons showed selective loss relative to peripherin+ neurons at later times in DRG infection. Profiling cell factors that were upregulated in VZV-infected DRG indicated that VZV infection induced marked pro-inflammatory responses, as well as proteins of the interferon pathway and neuroprotective responses. These neuropathologic changes observed in sensory ganglia infected with VZV may help to explain the neurologic sequelae often associated with zoster and PHN.
View details for DOI 10.1371/journal.ppat.1004989
View details for PubMedID 26090802
View details for PubMedCentralID PMC4474629
-
Single-Cell Mass Cytometry Analysis of Human Tonsil T Cell Remodeling by Varicella Zoster Virus
CELL REPORTS
2014; 8 (2): 632-644
Abstract
Although pathogens must infect differentiated host cells that exhibit substantial diversity, documenting the consequences of infection against this heterogeneity is challenging. Single-cell mass cytometry permits deep profiling based on combinatorial expression of surface and intracellular proteins. We used this method to investigate varicella-zoster virus (VZV) infection of tonsil T cells, which mediate viral transport to skin. Our results indicate that VZV induces a continuum of changes regardless of basal phenotypic and functional T cell characteristics. Contrary to the premise that VZV selectively infects T cells with skin trafficking profiles, VZV infection altered T cell surface proteins to enhance or induce these properties. Zap70 and Akt signaling pathways that trigger such surface changes were activated in VZV-infected naive and memory cells by a T cell receptor (TCR)-independent process. Single-cell mass cytometry is likely to be broadly relevant for demonstrating how intracellular pathogens modulate differentiated cells to support pathogenesis in the natural host.
View details for DOI 10.1016/j.celrep.2014.06.024
View details for Web of Science ID 000341569800030
View details for PubMedCentralID PMC4127309
-
Molecular mechanisms of varicella zoster virus pathogenesis
NATURE REVIEWS MICROBIOLOGY
2014; 12 (3): 197-210
Abstract
Varicella zoster virus (VZV) is the causative agent of varicella (chickenpox) and zoster (shingles). Investigating VZV pathogenesis is challenging as VZV is a human-specific virus and infection does not occur, or is highly restricted, in other species. However, the use of human tissue xenografts in mice with severe combined immunodeficiency (SCID) enables the analysis of VZV infection in differentiated human cells in their typical tissue microenvironment. Xenografts of human skin, dorsal root ganglia or foetal thymus that contains T cells can be infected with mutant viruses or in the presence of inhibitors of viral or cellular functions to assess the molecular mechanisms of VZV-host interactions. In this Review, we discuss how these models have improved our understanding of VZV pathogenesis.
View details for DOI 10.1038/nrmicro3215
View details for Web of Science ID 000331623900006
View details for PubMedID 24509782
View details for PubMedCentralID PMC4066823
-
An immunoreceptor tyrosine-based inhibition motif in varicella-zoster virus glycoprotein B regulates cell fusion and skin pathogenesis
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2013; 110 (5): 1911-1916
Abstract
Herpesvirus entry functions of the conserved glycoproteins gB and gH-gL have been delineated, but their role in regulating cell-cell fusion is poorly understood. Varicella-zoster virus (VZV) infection provides a valuable model for investigating cell-cell fusion because of the importance of this process for pathogenesis in human skin and sensory ganglia. The present study identifies a canonical immunoreceptor tyrosine-based inhibition motif (ITIM) in the gB cytoplasmic domain (gBcyt) and demonstrates that the gBcyt is a tyrosine kinase substrate. Orbitrap mass spectrometry confirmed that Y881, central to the ITIM, is phosphorylated. To determine whether the gBcyt ITIM regulates gB/gH-gL-induced cell-cell fusion in vitro, tyrosine residues Y881 and Y920 in the gBcyt were substituted with phenylalanine separately or together. Recombinant viruses with these substitutions were generated to establish their effects on syncytia formation in replication in vitro and in the human skin xenograft model of VZV pathogenesis. The Y881F substitution caused significantly increased cell-cell fusion despite reduced cell-surface gB. Importantly, the Y881F or Y881/920F substitutions in VZV caused aggressive syncytia formation, reducing cell-cell spread. These in vitro effects of aggressive syncytia formation translated to severely impaired skin infection in vivo. In contrast, the Y920F substitution did not affect virus replication in vitro or in vivo. These observations suggest that gB modulates cell-cell fusion via an ITIM-mediated Y881 phosphorylation-dependent mechanism, supporting a unique concept that intracellular signaling through this gBcyt motif regulates VZV syncytia formation and is essential for skin pathogenesis.
View details for DOI 10.1073/pnas.1216985110
View details for Web of Science ID 000314558100067
View details for PubMedID 23322733
View details for PubMedCentralID PMC3562845
-
3D Reconstruction of VZV Infected Cell Nuclei and PML Nuclear Cages by Serial Section Array Scanning Electron Microscopy and Electron Tomography
PLOS PATHOGENS
2012; 8 (6)
Abstract
Varicella-zoster virus (VZV) is a human alphaherpesvirus that causes varicella (chickenpox) and herpes zoster (shingles). Like all herpesviruses, the VZV DNA genome is replicated in the nucleus and packaged into nucleocapsids that must egress across the nuclear membrane for incorporation into virus particles in the cytoplasm. Our recent work showed that VZV nucleocapsids are sequestered in nuclear cages formed from promyelocytic leukemia protein (PML) in vitro and in human dorsal root ganglia and skin xenografts in vivo. We sought a method to determine the three-dimensional (3D) distribution of nucleocapsids in the nuclei of herpesvirus-infected cells as well as the 3D shape, volume and ultrastructure of these unique PML subnuclear domains. Here we report the development of a novel 3D imaging and reconstruction strategy that we term Serial Section Array-Scanning Electron Microscopy (SSA-SEM) and its application to the analysis of VZV-infected cells and these nuclear PML cages. We show that SSA-SEM permits large volume imaging and 3D reconstruction at a resolution sufficient to localize, count and distinguish different types of VZV nucleocapsids and to visualize complete PML cages. This method allowed a quantitative determination of how many nucleocapsids can be sequestered within individual PML cages (sequestration capacity), what proportion of nucleocapsids are entrapped in single nuclei (sequestration efficiency) and revealed the ultrastructural detail of the PML cages. More than 98% of all nucleocapsids in reconstructed nuclear volumes were contained in PML cages and single PML cages sequestered up to 2,780 nucleocapsids, which were shown by electron tomography to be embedded and cross-linked by an filamentous electron-dense meshwork within these unique subnuclear domains. This SSA-SEM analysis extends our recent characterization of PML cages and provides a proof of concept for this new strategy to investigate events during virion assembly at the single cell level.
View details for DOI 10.1371/journal.ppat.1002740
View details for Web of Science ID 000305987800013
View details for PubMedID 22685402
View details for PubMedCentralID PMC3369938
-
Signal transducer and activator of transcription 3 (STAT3) and survivin induction by varicella-zoster virus promote replication and skin pathogenesis
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2012; 109 (2): 600-605
Abstract
Varicella-zoster virus (VZV) is a human α-herpesvirus that causes varicella (chickenpox) during primary infection and zoster (shingles) upon reactivation. Like other viruses, VZV must subvert the intrinsic antiviral defenses of differentiated human cells to produce progeny virions. Accordingly, VZV inhibits the activation of the cellular transcription factors IFN regulatory factor 3 (IRF3) and signal transducers and activators of transcription 1 (STAT1), thereby downregulating antiviral factors, including IFNs. Conversely, in this study, we found that VZV triggers STAT3 phosphorylation in cells infected in vitro and in human skin xenografts in SCID mice in vivo and that STAT3 activation induces the anti-apoptotic protein survivin. Small-molecule inhibitors of STAT3 phosphorylation and survivin restrict VZV replication in vitro, and VZV infection of skin xenografts in vivo is markedly impaired by the administration of the phospho-STAT3 inhibitor S3I-201. STAT3 and survivin are required for malignant transformation caused by γ-herpesviruses, such as Kaposi's sarcoma virus. We show that STAT3 activation is also critical for VZV, a nononcogenic herpesvirus, via a survivin-dependent mechanism. Furthermore, STAT3 activation is critical for the life cycle of the virus because VZV skin infection is necessary for viral transmission and persistence in the human population. Therefore, we conclude that takeover of this major cell-signaling pathway is necessary, independent of cell transformation, for herpesvirus pathogenesis and that STAT3 activation and up-regulation of survivin is a common mechanism important for the pathogenesis of lytic as well as tumorigenic herpesviruses.
View details for DOI 10.1073/pnas.1114232109
View details for Web of Science ID 000298950200053
View details for PubMedID 22190485
View details for PubMedCentralID PMC3258638
-
Structure-function analysis of varicella-zoster virus glycoprotein H identifies domain-specific roles for fusion and skin tropism
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2011; 108 (45): 18412-18417
Abstract
Enveloped viruses require membrane fusion for cell entry and replication. For herpesviruses, this event is governed by the multiprotein core complex of conserved glycoproteins (g)B and gH/gL. The recent crystal structures of gH/gL from herpes simplex virus 2, pseudorabies virus, and Epstein-Barr virus revealed distinct domains that, surprisingly, do not resemble known viral fusogens. Varicella-zoster virus (VZV) causes chicken pox and shingles. VZV is an α-herpesvirus closely related to herpes simplex virus 2, enabling prediction of the VZV gH structure by homology modeling. We have defined specific roles for each gH domain in VZV replication and pathogenesis using structure-based site-directed mutagenesis of gH. The distal tip of domain (D)I was important for skin tropism, entry, and fusion. DII helices and a conserved disulfide bond were essential for gH structure and VZV replication. An essential (724)CXXC(727) motif was critical for DIII structural stability and membrane fusion. This assignment of domain-dependent mechanisms to VZV gH links elements of the glycoprotein structure to function in herpesvirus replication and virulence.
View details for DOI 10.1073/pnas.1111333108
View details for Web of Science ID 000296700000053
View details for PubMedID 22025718
View details for PubMedCentralID PMC3215059
-
Disruption of PML Nuclear Bodies Is Mediated by ORF61 SUMO-Interacting Motifs and Required for Varicella-Zoster Virus Pathogenesis in Skin
PLOS PATHOGENS
2011; 7 (8)
Abstract
Promyelocytic leukemia protein (PML) has antiviral functions and many viruses encode gene products that disrupt PML nuclear bodies (PML NBs). However, evidence of the relevance of PML NB modification for viral pathogenesis is limited and little is known about viral gene functions required for PML NB disruption in infected cells in vivo. Varicella-zoster virus (VZV) is a human alphaherpesvirus that causes cutaneous lesions during primary and recurrent infection. Here we show that VZV disrupts PML NBs in infected cells in human skin xenografts in SCID mice and that the disruption is achieved by open reading frame 61 (ORF61) protein via its SUMO-interacting motifs (SIMs). Three conserved SIMs mediated ORF61 binding to SUMO1 and were required for ORF61 association with and disruption of PML NBs. Mutation of the ORF61 SIMs in the VZV genome showed that these motifs were necessary for PML NB dispersal in VZV-infected cells in vitro. In vivo, PML NBs were highly abundant, especially in basal layer cells of uninfected skin, whereas their frequency was significantly decreased in VZV-infected cells. In contrast, mutation of the ORF61 SIMs reduced ORF61 association with PML NBs, most PML NBs remained intact and importantly, viral replication in skin was severely impaired. The ORF61 SIM mutant virus failed to cause the typical VZV lesions that penetrate across the basement membrane into the dermis and viral spread in the epidermis was limited. These experiments indicate that VZV pathogenesis in skin depends upon the ORF61-mediated disruption of PML NBs and that the ORF61 SUMO-binding function is necessary for this effect. More broadly, our study elucidates the importance of PML NBs for the innate control of a viral pathogen during infection of differentiated cells within their tissue microenvironment in vivo and the requirement for a viral protein with SUMO-binding capacity to counteract this intrinsic barrier.
View details for DOI 10.1371/journal.ppat.1002157
View details for Web of Science ID 000294298100008
View details for PubMedID 21901090
View details for PubMedCentralID PMC3161977
-
Entrapment of Viral Capsids in Nuclear PML Cages Is an Intrinsic Antiviral Host Defense against Varicella-Zoster Virus
PLOS PATHOGENS
2011; 7 (2)
Abstract
The herpesviruses, like most other DNA viruses, replicate in the host cell nucleus. Subnuclear domains known as promyelocytic leukemia protein nuclear bodies (PML-NBs), or ND10 bodies, have been implicated in restricting early herpesviral gene expression. These viruses have evolved countermeasures to disperse PML-NBs, as shown in cells infected in vitro, but information about the fate of PML-NBs and their functions in herpesvirus infected cells in vivo is limited. Varicella-zoster virus (VZV) is an alphaherpesvirus with tropism for skin, lymphocytes and sensory ganglia, where it establishes latency. Here, we identify large PML-NBs that sequester newly assembled nucleocapsids (NC) in neurons and satellite cells of human dorsal root ganglia (DRG) and skin cells infected with VZV in vivo. Quantitative immuno-electron microscopy revealed that these distinctive nuclear bodies consisted of PML fibers forming spherical cages that enclosed mature and immature VZV NCs. Of six PML isoforms, only PML IV promoted the sequestration of NCs. PML IV significantly inhibited viral infection and interacted with the ORF23 capsid surface protein, which was identified as a target for PML-mediated NC sequestration. The unique PML IV C-terminal domain was required for both capsid entrapment and antiviral activity. Similar large PML-NBs, termed clastosomes, sequester aberrant polyglutamine (polyQ) proteins, such as Huntingtin (Htt), in several neurodegenerative disorders. We found that PML IV cages co-sequester HttQ72 and ORF23 protein in VZV infected cells. Our data show that PML cages contribute to the intrinsic antiviral defense by sensing and entrapping VZV nucleocapsids, thereby preventing their nuclear egress and inhibiting formation of infectious virus particles. The efficient sequestration of virion capsids in PML cages appears to be the outcome of a basic cytoprotective function of this distinctive category of PML-NBs in sensing and safely containing nuclear aggregates of aberrant proteins.
View details for DOI 10.1371/journal.ppat.1001266
View details for Web of Science ID 000287698200004
View details for PubMedID 21304940
View details for PubMedCentralID PMC3033373
-
Varicella-Zoster Virus Immediate-Early Protein 62 Blocks Interferon Regulatory Factor 3 (IRF3) Phosphorylation at Key Serine Residues: a Novel Mechanism of IRF3 Inhibition among Herpesviruses
JOURNAL OF VIROLOGY
2010; 84 (18): 9240-9253
Abstract
Varicella-zoster virus (VZV) is an alphaherpesvirus that is restricted to humans. VZV infection of differentiated cells within the host and establishment of latency likely require evasion of innate immunity and limited secretion of antiviral cytokines. Since interferons (IFNs) severely limit VZV replication, we examined the ability of VZV to modulate the induction of the type I IFN response in primary human embryonic lung fibroblasts (HELF). IFN-beta production was not detected, and transcription of two interferon response factor 3 (IRF3)-dependent interferon-stimulated genes (ISGs), ISG54 and ISG56, in response to poly(I:C) stimulation was downregulated in VZV-infected HELF. Inhibition of IRF3 function did not require VZV replication; the viral immediate-early protein 62 (IE62) alone was sufficient to produce this effect. IE62 blocked TBK1-mediated IFN-beta secretion and IRF3 function, as shown in an IFN-stimulated response element (ISRE)-luciferase reporter assay. However, IRF3 function was preserved if constitutively active IRF3 (IRF3-5D) was expressed in VZV-infected or IE62-transfected cells, indicating that VZV interferes with IRF3 phosphorylation. IE62-mediated inhibition was mapped to blocking phosphorylation of at least three serine residues on IRF3. However, IE62 binding to TBK1 or IRF3 was not detected and IE62 did not perturb TBK1-IRF3 complex formation. IE62-mediated inhibition of IRF3 function was maintained even if IE62 transactivator activity was disrupted. Thus, IE62 has two critical but discrete roles following VZV entry: to induce expression of VZV genes and to disarm the IFN-dependent antiviral defense through a novel mechanism that prevents IRF3 phosphorylation.
View details for DOI 10.1128/JVI.01147-10
View details for Web of Science ID 000281110500025
View details for PubMedID 20631144
View details for PubMedCentralID PMC2937611
-
PREFACE
INTERNATIONAL JOURNAL FOR MULTISCALE COMPUTATIONAL ENGINEERING
2023; 21 (3): 0v
View details for Web of Science ID 000943295200001
-
Preface
VARICELLA-ZOSTER VIRUS
2023; 438: V
View details for Web of Science ID 000894551600001
-
Target highlights in CASP14: analysis of models by structure providers.
Proteins
2021
Abstract
The biological and functional significance of selected CASP14 targets are described by the authors of the structures. The authors highlight the most relevant features of the target proteins and discuss how well these features were reproduced in the respective submitted predictions. The overall ability to predict three-dimensional structures of proteins has improved remarkably in CASP14, and many difficult targets were modelled with impressive accuracy. For the first time in the history of CASP, the experimentalists not only highlighted that computational models can accurately reproduce the most critical structural features observed in their targets, but also envisaged that models could serve as a guidance for further studies of biologically-relevant properties of proteins. This article is protected by copyright. All rights reserved.
View details for DOI 10.1002/prot.26247
View details for PubMedID 34561912
-
Prospects for a safe COVID-19 vaccine.
Science translational medicine
2020
Abstract
Rapid development of an efficacious vaccine against the viral pathogen SARS-CoV-2, the cause of the coronavirus disease-2019 (COVID-19) pandemic, is essential, but rigorous studies are required to determine the safety of candidate vaccines. Here, on behalf of the Accelerating COVID-19 Therapeutic Interventions and Vaccines (ACTIV) Working Group, we evaluate research on the potential risk of immune enhancement of disease by vaccines and viral infections, including coronavirus infections, together with emerging data about COVID-19 disease. Vaccine-associated enhanced disease has been rarely encountered with existing vaccines or viral infections. Although animal models of SARS-CoV-2 infection may elucidate mechanisms of immune protection, we need observations of enhanced disease in people receiving candidate COVID-19 vaccines to understand the risk of immune enhancement of disease. Neither principles of immunity nor preclinical studies provide a basis for prioritizing among the COVID-19 vaccine candidates with respect to safety at this time. Rigorous clinical trial design and post-licensure surveillance should provide a reliable strategy to identify adverse events, including the potential for enhanced severity of COVID-19 disease, following vaccination.
View details for DOI 10.1126/scitranslmed.abe0948
View details for PubMedID 33077678
-
Publisher Correction: A glycoprotein B-neutralizing antibody structure at 2.8 A uncovers a critical domain for herpesvirus fusion initiation.
Nature communications
2020; 11 (1): 4398
Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
View details for DOI 10.1038/s41467-020-18385-w
View details for PubMedID 32859924
-
A perspective on potential antibody-dependent enhancement of SARS-CoV-2.
Nature
2020
Abstract
The possibility of antibody-dependent enhancement (ADE) of disease is a general concern for the development of vaccines and antibody therapies because the mechanisms that underlie antibody protection have the theoretical potential to amplify viral infections or trigger immunopathology. Observations relevant to the risks of ADE of disease require careful review at this critical point in the SARS-CoV-2 pandemic. At present, no clinical findings, immunologic assays or biomarkers are known to differentiate any severe viral infection from immune-enhanced disease, whether by antibodies, T cells or intrinsic host responses. In vitro systems and animal models do not predict the risk of ADE of disease, in part because protective and potentially detrimental antibody-mediated mechanisms are the same, and designing animal models depends on understanding how antiviral host responses may become harmful in people. The implications of our lack of knowledge are twofold. First, comprehensive studies are urgently needed to define clinical correlates of protective immunity against SARS-CoV-2. Second, since we cannot predict ADE of disease reliably after either vaccination or treatment with antibodies, regardless of what virus is the causative agent, it will be essential to depend on careful analysis of safety in humans as immune interventions for COVID-19 disease move forward.
View details for DOI 10.1038/s41586-020-2538-8
View details for PubMedID 32659783
-
Immunogenicity of Inactivated Varicella Zoster Vaccine in Autologous Hematopoietic Stem Cell Transplant Recipients and Patients With Solid or Hematologic Cancer.
Open forum infectious diseases
2020; 7 (7): ofaa172
Abstract
Background: In phase 3 trials, inactivated varicella zoster virus (VZV) vaccine (ZVIN) was well tolerated and efficacious against herpes zoster (HZ) in autologous hematopoietic stem cell transplant (auto-HSCT) recipients and patients with solid tumor malignancies receiving chemotherapy (STMc) but did not reduce HZ incidence in patients with hematologic malignancies (HMs). Here, we describe ZVIN immunogenicity from these studies.Methods: Patients were randomized to ZVIN or placebo (4 doses). Immunogenicity was assessed by glycoprotein enzyme-linked immunosorbent assay (gpELISA) and VZV interferon (IFN)-gamma enzyme-linked immunospot (ELISPOT) assay in patients receiving all 4 doses without developing HZ at the time of blood sampling.Results: Estimated geometric mean fold rise ratios (ZVIN/placebo) by gpELISA and IFN-y ELISPOT ~28 days post-dose 4 were 2.02 (95% confidence interval [CI], 1.53-2.67) and 5.41 (95% CI, 3.60-8.12) in auto-HSCT recipients; 1.88 (95% CI, 1.79-1.98) and 2.10 (95% CI, 1.69-2.62) in patients with STMc; and not assessed and 2.35 (95% CI, 1.81-3.05) in patients with HM.Conclusions: ZVIN immunogenicity was directionally consistent with clinical efficacy in auto-HSCT recipients and patients with STMc even though HZ protection and VZV immunity were not statistically correlated. Despite a lack of clinical efficacy in patients with HM, ZVIN immunogenicity was observed in this population. Immunological results did not predict vaccine efficacy in these 3 populations.Clinical trial registration: NCT01229267, NCT01254630.
View details for DOI 10.1093/ofid/ofaa172
View details for PubMedID 32665955
-
Deletion of Herpes Simplex Virus 1 MicroRNAs miR-H1 and miR-H6 Impairs Reactivation.
Journal of virology
2020; 94 (15)
Abstract
During all stages of infection, herpes simplex virus 1 (HSV-1) expresses viral microRNAs (miRNAs). There are at least 20 confirmed HSV-1 miRNAs, yet the roles of individual miRNAs in the context of viral infection remain largely uncharacterized. We constructed a recombinant virus lacking the sequences for miR-H1-5p and miR-H6-3p (17dmiR-H1/H6). The seed sequences for these miRNAs are antisense to each other and are transcribed from divergent noncoding RNAs in the latency-associated transcript (LAT) promoter region. Comparing phenotypes exhibited by the recombinant virus lacking these miRNAs to the wild type (17syn+), we found that during acute infection in cell culture, 17dmiR-H1/H6 exhibited a modest increase in viral yields. Analysis of pathogenesis in the mouse following footpad infection revealed a slight increase in virulence for 17dmiR-H1/H6 but no significant difference in the establishment or maintenance of latency. Strikingly, explant of latently infected dorsal root ganglia revealed a decreased and delayed reactivation phenotype. Further, 17dmiR-H1/H6 was severely impaired in epinephrine-induced reactivation in the rabbit ocular model. Finally, we demonstrated that deletion of miR-H1/H6 increased the accumulation of the LAT as well as several of the LAT region miRNAs. These results suggest that miR-H1/H6 plays an important role in facilitating efficient reactivation from latency.IMPORTANCE While HSV antivirals reduce the severity and duration of clinical disease in some individuals, there is no vaccine or cure. Therefore, understanding the mechanisms regulating latency and reactivation as a potential to elucidate targets for better therapeutics is important. There are at least 20 confirmed HSV-1 miRNAs, yet the roles of individual miRNAs in the context of viral infection remain largely uncharacterized. The present study focuses on two of the miRNAs (miR-H1/H6) that are encoded within the latency-associated transcript (LAT) region, a portion of the genome that has been associated with efficient reactivation. Here, we demonstrate that the deletion of the seed sequences of these miRNAs results in a severe reduction in reactivation of HSV-1 in the mouse and rabbit models. These results suggest a linkage between these miRNAs and reactivation.
View details for DOI 10.1128/JVI.00639-20
View details for PubMedID 32295910
-
Safety and efficacy of inactivated varicella zoster virus vaccine in immunocompromised patients with malignancies: a two-arm, randomised, double-blind, phase 3 trial.
The Lancet. Infectious diseases
2019
Abstract
BACKGROUND: Patients who are immunocompromised because of malignancy have an increased risk of herpes zoster and herpes zoster-related complications. We aimed to investigate the efficacy and safety of an inactivated varicella zoster virus (VZV) vaccine for herpes zoster prevention in patients with solid tumour or haematological malignancies.METHODS: This phase 3, two-arm, randomised, double-blind, placebo-controlled, multicentre trial with an adaptive design was done in 329 centres across 40 countries. The trial included adult patients with solid tumour malignancies receiving chemotherapy and those with haematological malignancies, either receiving or not receiving chemotherapy. Patients were randomly assigned (1:1) to receive four doses of VZV vaccine inactivated by gamma irradiation or placebo approximately 30 days apart. The patients, investigators, trial site staff, clinical adjudication committee, and sponsor's clinical and laboratory personnel were masked to the group assignment. The primary efficacy endpoint was herpes zoster incidence in patients with solid tumour malignancies receiving chemotherapy, which was assessed in the modified intention-to-treat population (defined as all randomly assigned patients who received at least one dose of inactivated VZV vaccine or placebo). The primary safety endpoint was serious adverse events up to 28 days after the fourth dose in patients with solid tumour malignancies receiving chemotherapy. Safety endpoints were assessed in all patients who received at least one dose of inactivated VZV vaccine or placebo and had follow-up data. This trial is registered (NCT01254630 and EudraCT 2010-023156-89).FINDINGS: Between June 27, 2011, and April 11, 2017, 5286 patients were randomly assigned to receive VZV vaccine inactivated by gamma irradiation (n=2637) or placebo (n=2649). The haematological malignancy arm was terminated early because of evidence of futility at a planned interim analysis; therefore, all prespecified haematological malignancy endpoints were deemed exploratory. In patients with solid tumour malignancies in the modified intention-to-treat population, confirmed herpes zoster occurred in 22 of 1328 (6·7 per 1000 person-years) VZV vaccine recipients and in 61 of 1350 (18·5 per 1000 person-years) placebo recipients. Estimated vaccine efficacy against herpes zoster in patients with solid tumour malignancies was 63·6% (97·5% CI 36·4 to 79·1), meeting the prespecified success criterion. In patients with solid tumour malignancies, serious adverse events were similar in frequency across treatment groups, occurring in 298 (22·5%) of 1322 patients who received the vaccine and in 283 (21·0%) of 1346 patients who received placebo (risk difference 1·5%, 95% CI -1·7 to 4·6). Vaccine-related serious adverse events were less than 1% in each treatment group. Vaccine-related injection-site reactions were more common in the vaccine group than in the placebo group. In the haematological malignancy group, VZV vaccine was well tolerated and estimated vaccine efficacy against herpes zoster was 16·8% (95% CI -17·8 to 41·3).INTERPRETATION: The inactivated VZV vaccine was well tolerated and efficacious for herpes zoster prevention in patients with solid tumour malignancies receiving chemotherapy, but was not efficacious for herpes zoster prevention in patients with haematological malignancies.FUNDING: Merck & Co, Inc.
View details for DOI 10.1016/S1473-3099(19)30310-X
View details for PubMedID 31399378
-
Current In Vivo Models of Varicella-Zoster Virus Neurotropism.
Viruses
2019; 11 (6)
Abstract
Varicella-zoster virus (VZV), an exclusively human herpesvirus, causes chickenpox and establishes a latent infection in ganglia, reactivating decades later to produce zoster and associated neurological complications. An understanding of VZV neurotropism in humans has long been hampered by the lack of an adequate animal model. For example, experimental inoculation of VZV in small animals including guinea pigs and cotton rats results in the infection of ganglia but not a rash. The severe combined immune deficient human (SCID-hu) model allows the study of VZV neurotropism for human neural sub-populations. Simian varicella virus (SVV) infection of rhesus macaques (RM) closely resembles both human primary VZV infection and reactivation, with analyses at early times after infection providing valuable information about the extent of viral replication and the host immune responses. Indeed, a critical role for CD4 T-cell immunity during acute SVV infection as well as reactivation has emerged based on studies using RM. Herein we discuss the results of efforts from different groups to establish an animal model of VZV neurotropism.
View details for DOI 10.3390/v11060502
View details for PubMedID 31159224
-
Will Measles Virus or Humanity Win the International "Fitness" Challenge?
Annual review of virology
2019; 6 (1): iii-vii
View details for DOI 10.1146/annurev-vi-06-072619-100011
View details for PubMedID 31567068
-
The C-terminus of varicella-zoster virus glycoprotein M contains trafficking motifs that mediate skin virulence in the SCID-human model of VZV pathogenesis.
Virology
2018; 523: 110–20
Abstract
Knowledge about the function of varicella-zoster virus glycoprotein M is limited; the requirement of gM for skin and neural tropism are unknown. VZV gM contains two predicted YXXPhi trafficking motifs and a dileucine motif in the carboxyl-terminus. We constructed a recombinant VZV with gM truncated from the first YXXPhi and five additional viruses with YXXPhi tyrosine substitutions, alone and in combination with dileucine substitution. All recombinant viruses grew to high titer but mutation of the membrane-proximal YXXPhi motif reduced plaque size in cultured cells and altered gM localization. C-terminus truncation had a pronounced effect on virion morphogenesis and plaque size, but not on overall replication kinetics in vitro. Mutation of gM trafficking motifs and truncation attenuated replication in human skin xenografts in vivo; gM truncation did not alter neurotropism. Our results demonstrate that the gM C-terminus is dispensable for virus replication in cultured cells but is important for skin pathogenesis.
View details for PubMedID 30119012
-
Inactivated varicella zoster vaccine in autologous haemopoietic stem-cell transplant recipients: an international, multicentre, randomised, double-blind, placebo-controlled trial
LANCET
2018; 391 (10135): 2116–27
Abstract
Recipients of autologous haemopoietic stem-cell transplants (auto-HSCT) have an increased risk of herpes zoster and herpes zoster-related complications. The aim of this study was to establish the efficacy and safety of an inactivated varicella zoster vaccine for the prevention of herpes zoster after auto-HSCT.In this randomised, double-blind, placebo-controlled phase 3 trial, participants were recruited from 135 medical centres (ie, stem-cell transplant centres and hospitals) in North America, South America, Europe, and Asia. Patients were eligible if they were aged 18 years or older, scheduled to receive an auto-HSCT within 60 days of enrolment, and had a history of varicella infection or were seropositive for antibodies to varicella zoster virus, or both. Exclusion criteria included a history of herpes zoster within the previous year of enrolment, and intended antiviral prophylaxis for longer than 6 months after transplantation. Participants were randomly assigned according to a central randomisation schedule generated by the trial statistician, to receive either the inactivated-virus vaccine from one of three consistency lots, a high-antigen lot, or placebo, stratified by age (<50 vs ≥50 years) and intended duration of antiviral prophylaxis after transplantation (≤3 months vs >3 to ≤6 months). Participants, investigators, trial staff, and the funder's clinical and laboratory personnel were masked to group assignment. Participants were given four doses of inactivated vaccine or placebo, with the first dose 5-60 days before auto-HSCT, and the second, third, and fourth doses at about 30, 60, and 90 days after transplantation. The primary efficacy endpoint was the incidence of herpes zoster, confirmed by PCR or adjudication by a masked clinical committee, or both, assessed in all participants randomly assigned to the vaccine consistency lot group or placebo group who received at least one dose of vaccine and had auto-HSCT. Safety was assessed in all randomised participants who received at least one dose of vaccine and had follow-up data. A prespecified vaccine efficacy success criterion required the lower bound of the 95% CI be higher than 25% for the relative reduction of the hazard ratio of herpes zoster infection in participants given the vaccine from one of the consistency lots compared with those given placebo. This trial is registered on ClinicalTrials.gov (NCT01229267) and EudraCT (2010-020150-34).Between Dec 7, 2010, and April 25, 2013, 560 participants were randomly assigned to the vaccine consistency lot group, 106 to the high-antigen lot group, and 564 to the placebo group. 249 (44%) of patients in the vaccine consistency lot group, 35 (33%) in the high-antigen lot group, and 220 (39%) in the placebo group discontinued before study end, mostly because of death or withdrawal. 51 participants were excluded from the primary efficacy endpoint analyses because they did not undergo auto-HSCT or were not vaccinated, or both (22 [4%] in the vaccine consistency lot group, and 29 [5%] in the placebo group). Mean follow-up for efficacy was 2·4 years (SD 1·3) in the vaccine consistency lot group and 2·3 years (SD 1·3) in the placebo group. 42 (8%) of 538 participants in the vaccine consistency lot group (32·9 per 1000 person-years) and 113 (21%) of 535 in the placebo group (91·9 per 1000 person-years) had a confirmed case of herpes zoster. The estimated vaccine efficacy was 63·8% (95% CI 48·4-74·6), meeting the pre-specified success criterion. For the combined vaccine groups versus the placebo group, the proportion of patients with serious adverse events (216 [33%] of 657 vs 181 [33%] of 554; risk difference 0·2%, 95% CI -5·1 to 5·5) and serious vaccine-related adverse events (five [1%] vs five [1%]; risk difference 0·1%, -1·4 to 1·1) were similar. Vaccine-related injection-site adverse events occurred more frequently in participants given vaccine than those given placebo (191 [29%] vs 36 [7%]; risk difference 22·6%, 95% CI 18·5-26·6; p<0·0001).This study shows for the first time in a large phase 3 trial that early vaccination of auto-HSCT recipients during the peri-transplant period can be effective for the prevention of an opportunistic infection like herpes zoster and that the vaccine is well tolerated.Merck & Co., Inc.
View details for PubMedID 29856344
-
Age-associated differences in infection of human skin in the SCID mouse model of varicella-zoster virus pathogenesis.
Journal of virology
2018
Abstract
Varicella-zoster virus (VZV) is the skin-tropic human alphaherpesvirus responsible for both varicella and herpes zoster. Varicella and herpes zoster skin lesions have similar morphology but herpes zoster occurs disproportionally in older individuals and is often associated with a more extensive local rash and severe zoster-related neuralgia. We hypothesized that skin aging could also influence the outcome of the anterograde axonal transport of VZV to skin. We utilized human skin xenografts maintained in immunodeficient (SCID) mice to study VZV-induced skin pathology in vivo in fetal and adult skin xenografts. Here we find that VZV replication is enhanced in skin from older compared to younger adults, correlating with clinical observations. In addition to measures of VZV infection, we examined the expression of type I interferon (IFN) pathway components in adult skin and investigated elements of the cutaneous proliferative and inflammatory response to VZV infection in vivo Our results demonstrated that VZV infection of adult skin triggers intrinsic IFN-mediated responses as we have described in VZV-infected fetal skin xenografts, including MxA as well as PML, in skin cells surrounding lesions. Further, we observed that VZV elicited altered cell-signaling, proliferative and inflammatory responses that are involved in wound healing, driven by follicular stem cells. These cellular changes are consistent with VZV-induced activation of STAT3 and suggest that VZV exploits the wound healing process to ensure efficient delivery of the virus to keratinocytes. Adult skin xenografts offer an approach to further investigate VZV-induced skin pathologies in vivoIMPORTANCE Varicella-zoster virus (VZV) is the agent responsible for both varicella and herpes zoster. Herpes zoster occurs disproportionally in older individuals and is often associated with a more extensive local rash and severe zoster-related neuralgia. To examine the effect of skin aging on VZV skin lesions, we utilized fetal and adult human skin xenografts maintained in immunodeficient (SCID) mice. We measured VZV-induced skin pathology, examined the expression of type I interferon (IFN) pathway components in adult skin, and investigated elements of the cutaneous proliferative and inflammatory response to VZV infection in vivo Our results demonstrate that characteristics of aging skin are preserved in xenografts, that VZV replication is enhanced in skin from older compared to younger adults, correlating with clinical observations, and that VZV infection elicits altered cell-signaling and inflammatory responses. Adult skin xenografts offer an approach to further investigate VZV-induced skin pathologies in vivo.
View details for PubMedID 29563288
-
HIV-1 inhibitory properties of eCD4-Igmim2 determined using an Env-mediated membrane fusion assay.
PloS one
2018; 13 (10): e0206365
Abstract
Human Immunodeficiency Virus-1 (HIV-1) entry is dependent on the envelope glycoprotein (Env) that is present on the virion and facilitates fusion between the envelope and the cellular membrane. The protein consists of two subunits, gp120 and gp41, with the former required for binding the CD4 receptor and either the CXCR4 or CCR5 coreceptor, and the latter for mediating fusion. The requirement of fusion for infection has made Env an attractive target for HIV therapy development and led to the FDA approval of enfuvirtide, a fusion inhibitor. Continued development of entry inhibitors is warranted because enfuvirtide resistant HIV-1 strains have emerged. In this study, a novel HIV-1 fusion assay was validated using neutralizing antibodies and then used to investigate the mechanism of action of eCD4-Igmim2, an HIV-1 inhibitor proposed to cooperatively bind the CD4 binding site and the sulfotyrosine-binding pocket of gp120. Greater reduction in fusion levels was observed with eCD4-Igmim2 in the fusion assay than all of the gp120 antibodies evaluated. Lab adapted isolates, HIV-1HXB2 and HIV-1YU2, were sensitive to eCD4-Igmim2 in the fusion assay, while primary isolates, HIV-1BG505 and HIV-1ZM651 were resistant. These results correlated with greater IC50 values for primary isolates compared to the lab adapted isolates observed in a virus neutralization assay. Analysis of gp120 models identified differences in the V1 and V2 domains that are associated with eCD4-Igmim2 sensitivity. This study highlights the use of a fusion assay to identify key areas for improving the potency of eCD4-Igmim2.
View details for PubMedID 30359435
-
Mass Cytometric Analysis of HIV Entry, Replication, and Remodeling in Tissue CD4(+) T Cells
CELL REPORTS
2017; 20 (4): 984–98
Abstract
To characterize susceptibility to HIV infection, we phenotyped infected tonsillar T cells by single-cell mass cytometry and created comprehensive maps to identify which subsets of CD4+ T cells support HIV fusion and productive infection. By comparing HIV-fused and HIV-infected cells through dimensionality reduction, clustering, and statistical approaches to account for viral perturbations, we identified a subset of memory CD4+ T cells that support HIV entry but not viral gene expression. These cells express high levels of CD127, the IL-7 receptor, and are believed to be long-lived lymphocytes. In HIV-infected patients, CD127-expressing cells preferentially localize to extrafollicular lymphoid regions with limited viral replication. Thus, CyTOF-based phenotyping, combined with analytical approaches to distinguish between selective infection and receptor modulation by viruses, can be used as a discovery tool.
View details for DOI 10.1016/j.celrep.2017.06.087
View details for Web of Science ID 000406198900019
View details for PubMedID 28746881
View details for PubMedCentralID PMC5560086
-
A phase III, double-blind, randomized, placebo-controlled, multicenter clinical trial to study the safety, tolerability, efficacy, and immunogenicity of inactivated VZV vaccine (ZVIN) in recipients of autologous hematopoietic stem cell transplants (auto-HSCT)
NATURE PUBLISHING GROUP. 2017: S17
View details for Web of Science ID 000424355300009
-
The Glycoprotein B Cytoplasmic Domain Lysine Cluster Is Critical for Varicella-Zoster Virus Cell-Cell Fusion Regulation and Infection
JOURNAL OF VIROLOGY
2017; 91 (1)
View details for DOI 10.1128/JVI.01707-16
View details for Web of Science ID 000393189200023
-
Dysregulated Glycoprotein B-Mediated Cell-Cell Fusion Disrupts Varicella-Zoster Virus and Host Gene Transcription during Infection
JOURNAL OF VIROLOGY
2017; 91 (1)
View details for DOI 10.1128/JVI.01613-16
View details for Web of Science ID 000393189200019
-
Varicella-Zoster Virus Glycoproteins: Entry, Replication, and Pathogenesis.
Current clinical microbiology reports
2016; 3 (4): 204-215
Abstract
Varicella-zoster virus (VZV), an alphaherpesvirus that causes chicken pox (varicella) and shingles (herpes zoster), is a medically important pathogen that causes considerable morbidity and, on occasion, mortality in immunocompromised patients. Herpes zoster can afflict the elderly with a debilitating condition, postherpetic neuralgia, triggering severe, untreatable pain for months or years. The lipid envelope of VZV, similar to all herpesviruses, contains numerous glycoproteins required for replication and pathogenesis.To summarize the current knowledge about VZV glycoproteins and their roles in cell entry, replication and pathogenesis.The functions for some VZV glycoproteins are known, such as gB, gH and gL in membrane fusion, cell-cell fusion regulation, and receptor binding properties. However, the molecular mechanisms that trigger or mediate VZV glycoproteins remains poorly understood.VZV glycoproteins are central to successful replication but their modus operandi during replication and pathogenesis remain elusive requiring further mechanistic based studies.
View details for DOI 10.1007/s40588-016-0044-4
View details for PubMedID 28367398
-
Dysregulated Glycoprotein B Mediated Cell-Cell Fusion Disrupts Varicella-Zoster Virus and Host Gene Transcription During Infection.
Journal of virology
2016
Abstract
The highly conserved herpesvirus glycoprotein complex gB/gH-gL mediates membrane fusion during virion entry and cell-cell fusion. Varicella-zoster virus (VZV) characteristically forms multinucleated cells, or syncytia, during the infection of human tissues, but little is known about this process. The cytoplasmic domain of VZV gB (gBcyt) has been implicated in cell-cell fusion regulation because a gB[Y881F] substitution causes hyperfusion. gBcyt regulation is necessary for VZV pathogenesis, as the hyperfusogenic mutant gB[Y881F] is severely attenuated in human skin xenografts. In this study, gBcyt-regulated fusion was investigated by comparing melanoma cells infected with wild-type-like VZV or hyperfusogenic mutants. The gB[Y881F] mutant exhibited dramatically accelerated syncytium formation in melanoma cells caused by fusion of infected cells with many uninfected cells, increased cytoskeleton reorganization, and rapid displacement of nuclei to dense central structures compared to pOka using live-cell confocal microscopy. VZV and human transcriptomes were concurrently investigated using whole transcriptome sequencing (RNA-seq) to identify viral and cellular responses induced when gBcyt regulation was disrupted by the gB[Y881F] substitution. The expression of four vital VZV genes, ORF61 and the genes for glycoproteins gC, gE, and gI, was significantly reduced at 36 h postinfection for the hyperfusogenic mutants. Importantly, hierarchical clustering demonstrated an association of differential gene expression with dysregulated gBcyt-mediated fusion. A subset of Ras GTPase genes linked to membrane remodeling were upregulated in cells infected with the hyperfusogenic mutants. These data implicate gBcyt in the regulation of gB fusion function that, if unmodulated, triggers cellular processes leading to hyperfusion that attenuates VZV infection.The highly infectious, human-restricted pathogen varicella-zoster virus (VZV) causes chickenpox and shingles. Postherpetic neuralgia (PHN) is a common complication of shingles that manifests as prolonged excruciating pain, which has proven difficult to treat. The formation of fused multinucleated cells in ganglia might be associated with this condition. An effective vaccine against VZV is available but not recommended for immunocompromised individuals, highlighting the need for new therapies. This study investigated the viral and cellular responses to hyperfusion, a condition where the usual constraints of cell membranes are overcome and cells form multinucleated cells. This process hinders VZV and is regulated by a viral glycoprotein, gB. A combination of live-cell imaging and next-generation genomics revealed an alteration in viral and cellular responses during hyperfusion that was caused by the loss of gB regulation. These studies reveal mechanisms central to VZV pathogenesis, potentially leading to improved therapies.
View details for PubMedID 27795423
-
Varicella-Zoster Virus Activates CREB, and Inhibition of the pCREB-p300/CBP Interaction Inhibits Viral Replication In Vitro and Skin Pathogenesis In Vivo.
Journal of virology
2016; 90 (19): 8686-8697
Abstract
Varicella-zoster virus (VZV) is an alphaherpesvirus that causes varicella upon primary infection and zoster upon reactivation from latency in sensory ganglion neurons. The replication of herpesviruses requires manipulation of cell signaling pathways. Notably, CREB, a factor involved in the regulation of several cellular processes, is activated upon infection of T cells with VZV. Here, we report that VZV infection also induced CREB phosphorylation in fibroblasts and that XX-650-23, a newly identified inhibitor of the phosphorylated-CREB (pCREB) interaction with p300/CBP, restricted cell-cell spread of VZV in vitro CREB phosphorylation did not require the viral open reading frame 47 (ORF47) and ORF66 kinases encoded by VZV. Evaluating the biological relevance of these observations during VZV infection of human skin xenografts in the SCID mouse model of VZV pathogenesis showed both that pCREB was upregulated in infected skin and that treatment with XX-650-23 reduced infectious-virus production and limited lesion formation compared to treatment with a vehicle control. Thus, processes of CREB activation and p300/CBP binding are important for VZV skin infection and may be targeted for antiviral drug development.Varicella-zoster virus (VZV) is a common pathogen that causes chicken pox and shingles. As with all herpesviruses, the infection is acquired for life, and the virus can periodically reactivate from latency. Although VZV infection is usually benign with few or no deleterious consequences, infection can be life threatening in immunocompromised patients. Otherwise healthy elderly individuals who develop zoster as a consequence of viral reactivation are at risk for postherpetic neuralgia (PHN), a painful and long-lasting complication. Current vaccines use a live attenuated virus that is usually safe but cannot be given to many immunodeficient patients and retains the capacity to establish latency and reactivate, causing zoster. Antiviral drugs are effective against severe VZV infections but have little impact on PHN. A better understanding of virus-host cell interactions is relevant for developing improved therapies to safely interfere with cellular processes that are crucial for VZV pathogenesis.
View details for DOI 10.1128/JVI.00920-16
View details for PubMedID 27440893
-
Role for the aV Integrin Subunit in Varicella-Zoster Virus-Mediated Fusion and Infection.
Journal of virology
2016; 90 (16): 7567-7578
Abstract
Varicella-zoster virus (VZV) is an alphaherpesvirus that causes varicella and herpes zoster. Membrane fusion is essential for VZV entry and the distinctive syncytium formation in VZV-infected skin and neuronal tissue. Herpesvirus fusion is mediated by a complex of glycoproteins gB and gH-gL, which are necessary and sufficient for VZV to induce membrane fusion. However, the cellular requirements of fusion are poorly understood. Integrins have been implicated to facilitate entry of several human herpesviruses, but their role in VZV entry has not yet been explored. To determine the involvement of integrins in VZV fusion, a quantitative cell-cell fusion assay was developed using a VZV-permissive melanoma cell line. The cells constitutively expressed a reporter protein and short hairpin RNAs (shRNAs) to knock down the expression of integrin subunits shown to be expressed in these cells by RNA sequencing. The αV integrin subunit was identified as mediating VZV gB/gH-gL fusion, as its knockdown by shRNAs reduced fusion levels to 60% of that of control cells. A comparable reduction in fusion levels was observed when an anti-αV antibody specific to its extracellular domain was tested in the fusion assay, confirming that the domain was important for VZV fusion. In addition, reduced spread was observed in αV knockdown cells infected with the VZV pOka strain relative to that of the control cells. This was demonstrated by reductions in plaque size, replication kinetics, and virion entry in the αV subunit knockdown cells. Thus, the αV integrin subunit is important for VZV gB/gH-gL fusion and infection.Varicella-zoster virus (VZV) is a highly infectious pathogen that causes chickenpox and shingles. A common complication of shingles is the excruciating condition called postherpetic neuralgia, which has proven difficult to treat. While a vaccine is now available, it is not recommended for immunocompromised individuals and its efficacy decreases with the recipient's age. These limitations highlight the need for new therapies. This study examines the role of integrins in membrane fusion mediated by VZV glycoproteins gB and gH-gL, a required process for VZV infection. This knowledge will further the understanding of VZV entry and provide insight into the development of better therapies.
View details for DOI 10.1128/JVI.00792-16
View details for PubMedID 27279620
View details for PubMedCentralID PMC4984616
-
Mutational analysis of varicella-zoster virus (VZV) immediate early protein (IE62) subdomains and their importance in viral replication
VIROLOGY
2016; 492: 82-91
Abstract
VZV IE62 is an essential, immediate-early, tegument protein and consists of five domains. We generated recombinant viruses carrying mutations in the first three IE62 domains and tested their influence on VZV replication kinetics. The mutations in domain I did not affect replication kinetics while domain II mutations, disrupting the DNA binding and dimerization domain (DBD), were lethal for VZV replication. Mutations in domain III of the nuclear localization signal (NLS) and the two phosphorylation sites S686A/S722A resulted in slower growth in early and late infection respectively and were associated with IE62 accumulation in the cytoplasm and nucleus respectively. This study mapped the functional domains of IE62 in context of viral infection, indicating that DNA binding and dimerization domain is essential for VZV replication. In addition, the correct localization of IE62, whether nuclear or cytoplasmic, at different points in the viral life cycle, is important for normal progression of VZV replication.
View details for DOI 10.1016/j.virol.2016.02.012
View details for Web of Science ID 000374209900010
View details for PubMedID 26914506
View details for PubMedCentralID PMC4826839
-
Longitudinal Kinetics of Cytomegalovirus-Specific T-Cell Immunity and Viral Replication in Infants With Congenital Cytomegalovirus Infection.
Journal of the Pediatric Infectious Diseases Society
2016; 5 (1): 14-20
Abstract
Congenital cytomegalovirus (CMV) is reported to affect up to 1% of all live births in the United States. T-cell immunity may be important for controlling CMV replication in congenital CMV-infected infants. We describe the natural history of CMV-specific T-cell evolution and CMV replication in infants with congenital CMV infection.Cytomegalovirus viral load, CMV urine culture, and CMV-specific CD4 and CD8 T-cell responses were assessed in a prospective longitudinal cohort of 51 infants with congenital CMV infection who were observed from birth to 3 years of age.We found a kinetic pattern of decreasing urinary CMV replication and increasing CMV-specific CD4 and CD8 T-cell responses during the first 3 years of life. We also found higher CMV-specific CD8 T-cell responses were associated with subsequent reduction of urine CMV viral load.For infants with congenital CMV infection, our data suggest an age-related maturation of both CMV-specific CD4 and CD8 T-cell immunity that is associated with an age-related decline in urinary CMV replication.
View details for DOI 10.1093/jpids/piu089
View details for PubMedID 26908487
-
Dissecting the Molecular Mechanisms of the Tropism of Varicella-Zoster Virus for Human T Cells.
Journal of virology
2016; 90 (7): 3284-3287
Abstract
Studies of varicella-zoster virus (VZV) tropism for T cells support their role in viral transport to the skin during primary infection. Multiparametric single-cell mass cytometry demonstrates that, instead of preferentially infecting skin-homing T cells, VZV alters cell signaling and remodels surface proteins to enhance T cell skin trafficking. Viral proteins dispensable in skin, such as that encoded by open reading frame 66, are necessary in T cells. Interference with VZV T cell tropism may offer novel strategies for drug and vaccine design.
View details for DOI 10.1128/JVI.03375-14
View details for PubMedID 26792747
View details for PubMedCentralID PMC4794656
-
Single cell mass cytometry reveals remodeling of human T cell phenotypes by varicella zoster virus
METHODS
2015; 90: 85-94
Abstract
The recent application of mass cytometry (CyTOF) to biology provides a 'systems' approach to monitor concurrent changes in multiple host cell factors at the single cell level. We used CyTOF to evaluate T cells infected with varicella zoster virus (VZV) infection, documenting virus-mediated phenotypic and functional changes caused by this T cell tropic human herpesvirus. Here we summarize our findings using two complementary panels of antibodies against surface and intracellular signaling proteins to elucidate the consequences of VZV-mediated perturbations on the surface and in signaling networks of infected T cells. CyTOF data was analyzed by several statistical, analytical and visualization tools including hierarchical clustering, orthogonal scaling, SPADE, viSNE, and SLIDE. Data from the mass cytometry studies demonstrated that VZV infection led to 'remodeling' of the surface architecture of T cells, promoting skin trafficking phenotypes and associated with concomitant activation of T-cell receptor and PI3-kinase pathways. This method offers a novel approach for understanding viral interactions with differentiated host cells important for pathogenesis.
View details for DOI 10.1016/j.ymeth.2015.07.008
View details for Web of Science ID 000365378600012
View details for PubMedID 26213183
View details for PubMedCentralID PMC4655147
-
Differential effects of Sp cellular transcription factors on viral promoter activation by varicella-zoster virus (VZV) IE62 protein
VIROLOGY
2015; 485: 47-57
Abstract
The immediate early (IE) 62 protein is the major varicella-zoster virus (VZV) regulatory factor. Analysis of the VZV genome revealed 40 predicted GC-rich boxes within 36 promoters. We examined effects of ectopic expression of Sp1-Sp4 on IE62- mediated transactivation of three viral promoters. Ectopic expression of Sp3 and Sp4 enhanced IE62 activation of ORF3 and gI promoters while Sp3 reduced IE62 activation of ORF28/29 promoter and VZV DNA replication. Sp2 reduced IE62 transactivation of gI while Sp1 had no significant influence on IE62 activation with any of these viral promoters. Electrophoretic mobility shift assays (EMSA) confirmed binding of Sp1 and Sp3 but not Sp2 and Sp4 to the gI promoter. Sp1-4 bound to IE62 and amino acids 238-258 of IE62 were important for the interaction with Sp3 and Sp4 as well as Sp1. This work shows that Sp family members have differential effects on IE62-mediated transactivation in a promoter-dependent manner.
View details for DOI 10.1016/j.virol.2015.06.031
View details for Web of Science ID 000363993100005
View details for PubMedID 26207799
View details for PubMedCentralID PMC4619144
-
Varicella-zoster virus (VZV) origin of DNA replication oriS influences origin-dependent DNA replication and flanking gene transcription
VIROLOGY
2015; 481: 179-186
Abstract
The VZV genome has two origins of DNA replication (oriS), each of which consists of an AT-rich sequence and three origin binding protein (OBP) sites called Box A, C and B. In these experiments, the mutation in the core sequence CGC of the Box A and C not only inhibited DNA replication but also inhibited both ORF62 and ORF63 expression in reporter gene assays. In contrast the Box B mutation did not influence DNA replication or flanking gene transcription. These results suggest that efficient DNA replication enhances ORF62 and ORF63 transcription. Recombinant viruses carrying these mutations in both sites and one with a deletion of the whole oriS were constructed. Surprisingly, the recombinant virus lacking both copies of oriS retained the capacity to replicate in melanoma and HELF cells suggesting that VZV has another origin of DNA replication.
View details for DOI 10.1016/j.virol.2015.02.049
View details for Web of Science ID 000355069000019
View details for PubMedID 25795313
View details for PubMedCentralID PMC4437856
-
A site of varicella-zoster virus vulnerability identified by structural studies of neutralizing antibodies bound to the glycoprotein complex gHgL
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2015; 112 (19): 6056-6061
Abstract
Varicella-zoster virus (VZV), of the family Alphaherpesvirinae, causes varicella in children and young adults, potentially leading to herpes zoster later in life on reactivation from latency. The conserved herpesvirus glycoprotein gB and the heterodimer gHgL mediate virion envelope fusion with cell membranes during virus entry. Naturally occurring neutralizing antibodies against herpesviruses target these entry proteins. To determine the molecular basis for VZV neutralization, crystal structures of gHgL were determined in complex with fragments of antigen binding (Fabs) from two human monoclonal antibodies, IgG-94 and IgG-RC, isolated from seropositive subjects. These structures reveal that the antibodies target the same site, composed of residues from both gH and gL, distinct from two other neutralizing epitopes identified by negative-stain electron microscopy and mutational analysis. Inhibition of gB/gHgL-mediated membrane fusion and structural comparisons with herpesvirus homologs suggest that the IgG-RC/94 epitope is in proximity to the site on VZV gHgL that activates gB. Immunization studies proved that the anti-gHgL IgG-RC/94 epitope is a critical target for antibodies that neutralize VZV. Thus, the gHgL/Fab structures delineate a site of herpesvirus vulnerability targeted by natural immunity.
View details for DOI 10.1073/pnas.1501176112
View details for Web of Science ID 000354390600062
View details for PubMedID 25918416
View details for PubMedCentralID PMC4434712
-
Have Universities Overbuilt Biomedical Research Facilities?
ISSUES IN SCIENCE AND TECHNOLOGY
2015; 31 (3): 35–36
View details for Web of Science ID 000353936200016
-
Autophagic flux without a block differentiates varicella-zoster virus infection from herpes simplex virus infection
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2015; 112 (1): 256-261
Abstract
Autophagy is a process by which misfolded and damaged proteins are sequestered into autophagosomes, before degradation in and recycling from lysosomes. We have extensively studied the role of autophagy in varicella-zoster virus (VZV) infection, and have observed that vesicular cells are filled with >100 autophagosomes that are easily detectable after immunolabeling for the LC3 protein. To confirm our hypothesis that increased autophagosome formation was not secondary to a block, we examined all conditions of VZV infection as well as carrying out two assessments of autophagic flux. We first investigated autophagy in human skin xenografts in the severe combined immunodeficiency (SCID) mouse model of VZV pathogenesis, and observed that autophagosomes were abundant in infected human skin tissues. We next investigated autophagy following infection with sonically prepared cell-free virus in cultured cells. Under these conditions, autophagy was detected in a majority of infected cells, but was much less than that seen after an infected-cell inoculum. In other words, inoculation with lower-titered cell-free virus did not reflect the level of stress to the VZV-infected cell that was seen after inoculation of human skin in the SCID mouse model or monolayers with higher-titered infected cells. Finally, we investigated VZV-induced autophagic flux by two different methods (radiolabeling proteins and a dual-colored LC3 plasmid); both showed no evidence of a block in autophagy. Overall, therefore, autophagy within a VZV-infected cell was remarkably different from autophagy within an HSV-infected cell, whose genome contains two modifiers of autophagy, ICP34.5 and US11, not present in VZV.
View details for DOI 10.1073/pnas.1417878112
View details for Web of Science ID 000347447100062
View details for PubMedID 25535384
View details for PubMedCentralID PMC4291665
-
Varicella-zoster virus infections in patients treated with fingolimod: risk assessment and consensus recommendations for management.
JAMA neurology
2015; 72 (1): 31-39
Abstract
Varicella-zoster virus (VZV) infections increasingly are reported in patients with multiple sclerosis (MS) and constitute an area of significant concern, especially with the advent of more disease-modifying treatments in MS that affect T-cell-mediated immunity.To assess the incidence, risk factors, and clinical characteristics of VZV infections in fingolimod-treated patients and provide recommendations for prevention and management.Rates of VZV infections in fingolimod clinical trials are based on pooled data from the completed controlled phases 2 and 3 studies (3916 participants) and ongoing uncontrolled extension phases (3553 participants). Male and female patients aged 18 through 55 years (18-60 years for the phase 2 studies) and diagnosed as having relapsing-remitting MS were eligible to participate in these studies. In the postmarketing setting, reporting rates since 2010 were evaluated.In clinical trials, patients received fingolimod at a dosage of 0.5 or 1.25 mg/d, interferon beta-1a, or placebo. In the postmarketing setting, all patients received fingolimod, 0.5 mg/d (total exposure of 54 000 patient-years at the time of analysis).Calculation of the incidence rate of VZV infection per 1000 patient-years was based on the reporting of adverse events in the trials and the postmarketing setting.Overall, in clinical trials, VZV rates of infection were low but higher with fingolimod compared with placebo (11 vs 6 per 1000 patient-years). A similar rate was confirmed in the ongoing extension studies. Rates reported in the postmarketing settings were comparable (7 per 1000 patient-years) and remained stable over time. Disproportionality in reporting herpes zoster infection was higher for patients receiving fingolimod compared with those receiving other disease-modifying treatments (empirical Bayes geometric mean, 2.57 [90% CI, 2.26-2.91]); the proportion of serious herpes zoster infections was not higher than the proportion for other treatments (empirical Bayes geometric mean, 1.88 [90% CI, 0.87-3.70]). Corticosteroid treatment for relapses might be a risk factor for VZV reactivation.Rates of VZV infections in clinical trials were low with fingolimod, 0.5 mg/d, but higher than in placebo recipients. Rates reported in the postmarketing setting are comparable. We found no sign of risk accumulation with longer exposure. Serious or complicated cases of herpes zoster were uncommon. We recommend establishing the patient's VZV immune status before initiating fingolimod therapy and immunization for patients susceptible to primary VZV infection. Routine antiviral prophylaxis is not needed, but using concomitant pulsed corticosteroid therapy beyond 3 to 5 days requires an individual risk-benefit assessment. Vigilance to identify early VZV symptoms is important to allow timely antiviral treatment.
View details for DOI 10.1001/jamaneurol.2014.3065
View details for PubMedID 25419615
-
The cytoplasmic domain of varicella-zoster virus glycoprotein h regulates syncytia formation and skin pathogenesis.
PLoS pathogens
2014; 10 (5)
View details for DOI 10.1371/journal.ppat.1004173
View details for PubMedID 24874654
-
Cellular transcription factor YY1 mediates the varicella-zoster virus (VZV) IE62 transcriptional activation
VIROLOGY
2014; 449: 244-253
Abstract
Several cellular transcription factors have been shown to be involved in IE62-mediated activation. The YY1 cellular transcription factor has activating and repressive effects on gene transcription. Analysis of the VZV genome revealed 19 postulated YY1 binding sites located within putative promoters of 16 VZV genes. Electrophoretic mobility shift assays (EMSA) confirmed the binding of YY1 to ORF10, ORF28/29 and gI promoters and the mutation of these binding sites inhibited YY1 binding and the promoter activation by IE62 alone or following VZV infection. Mutation of the ORF28/29 YY1 site in the VZV genome displayed insignificant influence on virus growth in melanoma cells; but it inhibited the virus replication significantly at day 5 and 6 post infection in HELF cells. This work suggests a novel role for the cellular factor YY1 in VZV replication through the mediation of IE62 activation of viral gene expression.
View details for DOI 10.1016/j.virol.2013.11.029
View details for Web of Science ID 000330094100028
View details for PubMedID 24418559
View details for PubMedCentralID PMC3901949
-
Multiparametric high dimensional analysis of normal & VZV infected human tonsil T cells at a single cell resolution by mass cytometry
ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD. 2013: 298
View details for DOI 10.1016/j.cyto.2013.06.236
View details for Web of Science ID 000324013700245
-
Regulation of the varicella-zoster virus ORF3 promoter by cellular and viral factors.
Virology
2013; 440 (2): 171-181
Abstract
The varicella zoster virus (VZV) immediate early 62 protein (IE62) activates most if not all identified promoters of VZV genes and also some minimum model promoters that contain only a TATA box element. Analysis of the DNA elements that function in IE62 activation of the VZV ORF3 promoter revealed that the 100 nucleotides before the translation start site of the ORF3 gene contains the promoter elements. This promoter lacks any functional TATA box element. Cellular transcription factors Sp1, Sp3 and YY1 bind to the promoter, and mutation of their binding sites inhibited ORF3 gene expression. VZV regulatory proteins, IE63 and ORF29, ORF61 and ORF10 proteins inhibited IE62-mediated activation of this promoter. Mutation of the Sp1/Sp3 binding site in the VZV genome did not alter VZV replication kinetics. This work suggests that Sp family proteins contribute to the activation of VZV promoters by IE62 in the absence of functional TATA box.
View details for DOI 10.1016/j.virol.2013.02.019
View details for PubMedID 23523134
View details for PubMedCentralID PMC3640663
-
ORF11 Protein Interacts with the ORF9 Essential Tegument Protein in Varicella-Zoster Virus Infection
JOURNAL OF VIROLOGY
2013; 87 (9): 5106-5117
Abstract
The tegument proteins encoded by ORF11 and ORF9 of varicella-zoster virus (VZV) are conserved among all alphaherpesvirus. We previously demonstrated that the ORF9 gene is essential, whereas ORF11 is dispensable in vitro but its deletion severely impairs VZV infection of skin xenografts in the SCID mouse model in vivo. Here we report that ORF11 protein interacts with ORF9 protein in infected cells as well as in the absence of other viral proteins, and we have mapped the ORF11 protein domain involved in their interaction. Although ORF11 is an RNA binding protein, the interaction between ORF11 and ORF9 proteins was not mediated by RNA or DNA bridging. VZV recombinants with mutations preventing ORF11 protein binding to ORF9 protein had no effect on 6-day growth kinetics based on plaque numbers, but plaque sizes were reduced in vitro. However, disruption of the ORF11 and ORF9 protein interaction was associated with failure to replicate in skin xenografts in vivo. Further, we demonstrate that in the absence of their interaction, the ORF9 protein displays an identical cellular localization, accumulating in the trans-Golgi region, whereas the ORF11 protein exhibits aberrant localization, dispersing throughout the cytoplasm. Overall, our observations suggest that while complete tegument assembly may not be necessary for VZV replication in vitro, the interaction between the ORF11 and ORF9 proteins appears to be critical for the proper localization of ORF11 protein to the assembly complex and for production of infectious virus during VZV pathogenesis in skin.
View details for DOI 10.1128/JVI.00102-13
View details for Web of Science ID 000317416400029
View details for PubMedID 23427162
View details for PubMedCentralID PMC3624291
-
Identification of a Hydrophobic Domain in Varicella-Zoster Virus ORF61 Necessary for ORF61 Self-Interaction, Viral Replication, and Skin Pathogenesis
JOURNAL OF VIROLOGY
2013; 87 (7): 4075-4079
Abstract
The varicella-zoster virus (VZV) ORF61 protein is necessary for normal replication in vitro and virulence in human skin xenografts in the severe combined immunodeficiency mouse model in vivo. These experiments identify a hydrophobic domain that mediates ORF61 self-interaction. While not needed to inhibit host cell defenses, disruption of this domain (residues 250 to 320) severely impairs VZV growth, transactivation of the immediate early 63 and glycoprotein E genes, and the pathogenesis of VZV skin infection in vivo.
View details for DOI 10.1128/JVI.02963-12
View details for Web of Science ID 000315957100042
View details for PubMedID 23345513
View details for PubMedCentralID PMC3624212
-
Herpes Simplex Virus 1 Tropism for Human Sensory Ganglion Neurons in the Severe Combined Immunodeficiency Mouse Model of Neuropathogenesis
JOURNAL OF VIROLOGY
2013; 87 (5): 2791-2802
Abstract
The tropism of herpes simplex virus (HSV-1) for human sensory neurons infected in vivo was examined using dorsal root ganglion (DRG) xenografts maintained in mice with severe combined immunodeficiency (SCID). In contrast to the HSV-1 lytic infectious cycle in vitro, replication of the HSV-1 F strain was restricted in human DRG neurons despite the absence of adaptive immune responses in SCID mice, allowing the establishment of neuronal latency. At 12 days after DRG inoculation, 26.2% of human neurons expressed HSV-1 protein and 13.1% expressed latency-associated transcripts (LAT). Some infected neurons showed cytopathic changes, but HSV-1, unlike varicella-zoster virus (VZV), only rarely infected satellite cells and did not induce fusion of neuronal and satellite cell plasma membranes. Cell-free enveloped HSV-1 virions were observed, indicating productive infection. A recombinant HSV-1-expressing luciferase exhibited less virulence than HSV-1 F in the SCID mouse host, enabling analysis of infection in human DRG xenografts for a 61-day interval. At 12 days after inoculation, 4.2% of neurons expressed HSV-1 proteins; frequencies increased to 32.1% at 33 days but declined to 20.8% by 61 days. Frequencies of LAT-positive neurons were 1.2% at 12 days and increased to 40.2% at 33 days. LAT expression remained at 37% at 61 days, in contrast to the decline in neurons expressing viral proteins. These observations show that the progression of HSV-1 infection is highly restricted in human DRG, and HSV-1 genome silencing occurs in human neurons infected in vivo as a consequence of virus-host cell interactions and does not require adaptive immune control.
View details for DOI 10.1128/JVI.01375-12
View details for Web of Science ID 000314876900038
View details for PubMedID 23269807
View details for PubMedCentralID PMC3571385
-
Measles humoral and cell-mediated immunity in children aged 5-10 years after primary measles immunization administered at 6 or 9 months of age.
journal of infectious diseases
2013; 207 (4): 574-582
Abstract
Given the high infant measles mortality rate, there is interest in whether a measles immunization regimen beginning at <12 months of age provides lasting immunity.Measles-specific immune responses were evaluated in 70 children aged 5-10 years after primary measles vaccine administered at 6, 9, or 12 months.At 5-10 years of age, the stimulation index for measles T-cell proliferation was 11.4 (SE, 1.3), 10.9 (SE, 1.5), and 14.4 (SE 2.1) when the first measles dose was given at 6, 9, or 12 months, respectively. Neutralizing antibody concentration (geometric mean titer [GMT]) in those immunized at 6 months of age was 125 mIU/mL (95% confidence interval [CI], 42-377) in the presence of passive antibodies (PAs) and 335 mIU/mL (95% CI, 211-531) in those without PAs; in those immunized at 9 months, GMTs were 186 mIU/mL (95% CI, 103-335) and 1080 mIU/mL (95% CI, 642-1827) in the presence and absence of PAs, respectively. The GMT was 707 mIU/mL (95% CI, 456-1095) when vaccine was administered at 12 months (P ≤ .04).Measles-specific T-cell responses were sustained at 5-10 years of age regardless of age at time of primary measles immunization. Neutralizing antibody concentrations were lower in cohorts given the first vaccine dose at 6 months of age and in the presence of PAs; however, responses could be boosted by subsequent doses. Starting measles vaccination at <12 months of age may be beneficial during measles outbreaks or in endemic areas.
View details for DOI 10.1093/infdis/jis719
View details for PubMedID 23300162
View details for PubMedCentralID PMC3549597
-
Innate Immune Dysfunction is Associated with Enhanced Disease Severity In Infants with Severe Respiratory Syncytial Virus Bronchiolitis
JOURNAL OF INFECTIOUS DISEASES
2013; 207 (4): 574-582
Abstract
Given the high infant measles mortality rate, there is interest in whether a measles immunization regimen beginning at <12 months of age provides lasting immunity.Measles-specific immune responses were evaluated in 70 children aged 5-10 years after primary measles vaccine administered at 6, 9, or 12 months.At 5-10 years of age, the stimulation index for measles T-cell proliferation was 11.4 (SE, 1.3), 10.9 (SE, 1.5), and 14.4 (SE 2.1) when the first measles dose was given at 6, 9, or 12 months, respectively. Neutralizing antibody concentration (geometric mean titer [GMT]) in those immunized at 6 months of age was 125 mIU/mL (95% confidence interval [CI], 42-377) in the presence of passive antibodies (PAs) and 335 mIU/mL (95% CI, 211-531) in those without PAs; in those immunized at 9 months, GMTs were 186 mIU/mL (95% CI, 103-335) and 1080 mIU/mL (95% CI, 642-1827) in the presence and absence of PAs, respectively. The GMT was 707 mIU/mL (95% CI, 456-1095) when vaccine was administered at 12 months (P ≤ .04).Measles-specific T-cell responses were sustained at 5-10 years of age regardless of age at time of primary measles immunization. Neutralizing antibody concentrations were lower in cohorts given the first vaccine dose at 6 months of age and in the presence of PAs; however, responses could be boosted by subsequent doses. Starting measles vaccination at <12 months of age may be beneficial during measles outbreaks or in endemic areas.
View details for DOI 10.1093/infdis/jis719
View details for Web of Science ID 000314121800005
View details for PubMedCentralID PMC3549597
-
An Sp1/Sp3 Site in the Downstream Region of Varicella-Zoster Virus (VZV) oriS Influences Origin-Dependent DNA Replication and Flanking Gene Transcription and Is Important for VZV Replication In Vitro and in Human Skin
JOURNAL OF VIROLOGY
2012; 86 (23): 13070-13080
Abstract
The distribution and orientation of origin-binding protein (OBP) sites are the main architectural contrasts between varicella-zoster virus (VZV) and herpes simplex virus (HSV) origins of DNA replication (oriS). One important difference is the absence of a downstream OBP site in VZV, raising the possibility that an alternative cis element may replace its function. Our previous work established that Sp1, Sp3, and YY1 bind to specific sites within the downstream region of VZV oriS; we hypothesize that one or both of these sites may be the alternative cis element(s). Here, we show that the mutation of the Sp1/Sp3 site decreases DNA replication and transcription from the adjacent ORF62 and ORF63 promoters following superinfection with VZV. In contrast, in the absence of DNA replication or in transfection experiments with ORF62, only ORF63 transcription is affected. YY1 site mutations had no significant effect on either process. Recombinant viruses containing these mutations were then constructed. The Sp1/Sp3 site mutant exhibited a significant decrease in virus growth in MeWo cells and in human skin xenografts, while the YY1 site mutant virus grew as well as the wild type in MeWo cells, even showing a late increase in VZV replication in skin xenografts following infection. These results suggest that the Sp1/Sp3 site plays an important role in both VZV origin-dependent DNA replication and ORF62 and ORF63 transcription and that, in contrast to HSV, these events are linked during virus replication.
View details for DOI 10.1128/JVI.01538-12
View details for Web of Science ID 000310585300056
View details for PubMedID 22933283
View details for PubMedCentralID PMC3497629
-
The Attenuated Genotype of Varicella-Zoster Virus Includes an ORF0 Transitional Stop Codon Mutation
JOURNAL OF VIROLOGY
2012; 86 (19): 10695-10703
Abstract
Varicella-zoster virus (VZV) is the first of the human herpesviruses to be attenuated and subsequently approved as a live vaccine to prevent varicella and herpes zoster. Both the attenuated VZV vaccine, called vaccine Oka or vOka, and the parental strain pOka have been completely sequenced. Yet the specific determinants of attenuation are uncertain. The open reading frame (ORF) with the most single nucleotide polymorphisms (SNPs), ORF62, encodes the regulatory protein IE62, but IE62 studies have failed to define a specific SNP associated with attenuation. We have completed next-generation sequencing of the VZV Ellen genome, a strain known to be highly attenuated by its very limited replication in human skin xenografts in the SCID mouse model of VZV pathogenesis. A comparative analysis of the Ellen sequence with all other complete VZV sequences was extremely informative. In particular, an unexpected finding was a stop codon mutation in Ellen ORF0 (herpes simplex virus UL56 homolog) identical to one found in vOka, combined with the absence of polymorphisms in most Ellen ORFs that were known to be mutated in vOka. The mutated ORF0 protein was also imaged in both two dimensions and three dimensions by confocal microscopy. The probability of two VZV strains not connected by a recent common ancestor having an identical ORF0 SNP by chance would be 1 × 10(-8), in other words, extremely unlikely. Taken together, these bioinformatics analyses strongly suggest that the stop codon ORF0 SNP is one of the determinants of the attenuation genotype of live VZV vaccines.
View details for DOI 10.1128/JVI.01067-12
View details for Web of Science ID 000308740700044
View details for PubMedID 22837206
View details for PubMedCentralID PMC3457260
-
Apparent Expression of Varicella-Zoster Virus Proteins in Latency Resulting from Reactivity of Murine and Rabbit Antibodies with Human Blood Group A Determinants in Sensory Neurons
JOURNAL OF VIROLOGY
2012; 86 (1): 578-583
Abstract
Analyses of varicella-zoster virus (VZV) protein expression during latency have been discordant, with rare to many positive neurons detected. We show that ascites-derived murine and rabbit antibodies specific for VZV proteins in vitro contain endogenous antibodies that react with human blood type A antigens in neurons. Apparent VZV neuronal staining and blood type A were strongly associated (by a χ² test, α = 0.0003). Adsorption of ascites-derived monoclonal antibodies or antiserum with type A erythrocytes or the use of in vitro-derived VZV monoclonal antibodies eliminated apparent VZV staining. Animal-derived antibodies must be screened for anti-blood type A reactivity to avoid misidentification of viral proteins in the neurons of the 30 to 40% of individuals who are blood type A.
View details for DOI 10.1128/JVI.05950-11
View details for Web of Science ID 000298347700055
View details for PubMedID 22013055
View details for PubMedCentralID PMC3255922
-
Investigation of varicella-zoster virus neurotropism and neurovirulence using SCID mouse-human DRG xenografts
JOURNAL OF NEUROVIROLOGY
2011; 17 (6): 570-577
Abstract
Varicella-zoster virus (VZV) is a medically important human alphaherpesvirus. Investigating pathogenic mechanisms that contribute to VZV neurovirulence are made difficult by a marked host restriction. Our approach to investigating VZV neurotropism and neurovirulence has been to develop a mouse-human xenograft model in which human dorsal root ganglia (DRG) are maintained in severe compromised immunodeficient (SCID) mice. In this review, we will describe our key findings using this model in which we have demonstrated that VZV infection of SCID DRG xenograft results in rapid and efficient spread, enabled by satellite cell infection and polykaryon formation, which facilitates robust viral replication and release of infectious virus. In neurons that persist following this acute replicative phase, VZV genomes are present at low frequency with limited gene transcription and no protein synthesis, a state that resembles VZV latency in the natural human host. VZV glycoprotein I and interaction between glycoprotein I and glycoprotein E are critical for neurovirulence. Our work demonstrates that the DRG model can reveal characteristics about VZV replication and long-term persistence of latent VZV genomes in human neuronal tissues, in vivo, in an experimental system that may contribute to our knowledge of VZV neuropathogenesis.
View details for DOI 10.1007/s13365-011-0066-x
View details for Web of Science ID 000299121300009
View details for PubMedID 22161683
-
Varicella Zoster Virus ORF25 Gene Product: An Essential Hub Protein Linking Encapsidation Proteins and the Nuclear Egress Complex
JOURNAL OF PROTEOME RESEARCH
2011; 10 (12): 5374-5382
Abstract
Varicella zoster virus (VZV) ORF25 is a 156 amino acid protein belonging to the approximately 40 core proteins that are conserved throughout the Herpesviridae. By analogy to its functional orthologue UL33 in Herpes simplex virus 1 (HSV-1), ORF25 is thought to be a component of the terminase complex. To investigate how cleavage and encapsidation of viral DNA links to the nuclear egress of mature capsids in VZV, we tested 10 VZV proteins that are predicted to be involved in either of the two processes for protein interactions against each other using three independent protein-protein interaction (PPI) detection systems: the yeast-two-hybrid (Y2H) system, a luminescence based MBP pull-down interaction screening assay (LuMPIS), and a bioluminescence resonance energy transfer (BRET) assay. A set of 20 interactions was consistently detected by at least 2 methods and resulted in a dense interaction network between proteins associated in encapsidation and nuclear egress. The results indicate that the terminase complex in VZV consists of ORF25, ORF30, and ORF45/42 and support a model in which both processes are closely linked to each other. Consistent with its role as a central hub for protein interactions, ORF25 is shown to be essential for VZV replication.
View details for DOI 10.1021/pr200628s
View details for Web of Science ID 000297537200010
View details for PubMedID 21988664
View details for PubMedCentralID PMC3230707
-
A Sequence within the Varicella-Zoster Virus (VZV) OriS Is a Negative Regulator of DNA Replication and Is Bound by a Protein Complex Containing the VZV ORF29 Protein
JOURNAL OF VIROLOGY
2011; 85 (23): 12188-12200
Abstract
The architecture of the varicella-zoster virus (VZV) origin of DNA replication (OriS) differs significantly from that of the herpes simplex virus (HSV) DNA replication origin. Novel aspects of the VZV OriS include a GA-rich region, three binding sites for the VZV origin-binding protein (OBP) all on the same strand and oriented in the same direction, and a partial OBP binding site of unknown function. We have designated this partial binding site Box D and have investigated the role it plays in DNA replication and flanking gene expression. This has been done with a model system using a replication-competent plasmid containing OriS and a replication- and transcription-competent dual-luciferase reporter plasmid containing both the OriS and the intergenic region between VZV open reading frames (ORFs) 62 and 63. We have found that (i) Box D is a negative regulator of DNA replication independent of flanking gene expression, (ii) the mutation of Box D results in a decrease in flanking gene expression, thus a sequence within the VZV OriS affects transcription, which is in contrast to results reported for HSV-1, (iii) there is a specific Box D complex formed with infected cell extracts in electrophoretic mobility shift assay experiments, (iv) supershift assays show that this complex contains the VZV ORF29 single-strand DNA-binding protein, and (v) the formation of this complex is dependent on the presence of CGC motifs in Box D and its downstream flanking region. These findings show that the VZV ORF29 protein, while required for DNA replication, also plays a novel role in the suppression of that process.
View details for DOI 10.1128/JVI.05501-11
View details for Web of Science ID 000296708100009
View details for PubMedID 21937644
View details for PubMedCentralID PMC3209344
-
Varicella-Zoster Virus Infection Triggers Formation of an Interleukin-1 beta (IL-1 beta)-processing Inflammasome Complex
JOURNAL OF BIOLOGICAL CHEMISTRY
2011; 286 (20): 17921-17933
Abstract
Innate cellular immunity is the immediate host response against pathogens, and activation of innate immunity also modulates the induction of adaptive immunity. The nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) are a family of intracellular receptors that recognize conserved patterns associated with intracellular pathogens, but information about their role in the host defense against DNA viruses is limited. Here we report that varicella-zoster virus (VZV), an alphaherpesvirus that is the causative agent of varicella and herpes zoster, induces formation of the NLRP3 inflammasome and the associated processing of the proinflammatory cytokine IL-1β by activated caspase-1 in infected cells. NLRP3 inflammasome formation was induced in VZV-infected human THP-1 cells, which are a transformed monocyte cell line, primary lung fibroblasts, and melanoma cells. Absent in melanoma gene-2 (AIM2) is an interferon-inducible protein that can form an alternative inflammasome complex with caspase-1 in virus-infected cells. Experiments in VZV-infected melanoma cells showed that NLRP3 protein recruits the adaptor protein ASC and caspase-1 to form an NLRP3 inflammasome complex independent of AIM2 protein and in the absence of free radical reactive oxygen species release. NLRP3 was also expressed extensively in infected skin xenografts in the severe combined immunodeficiency mouse model of VZV pathogenesis in vivo. We conclude that NLRP3 inflammasome formation is an innate cellular response to infection with this common pathogenic human herpesvirus.
View details for DOI 10.1074/jbc.M110.210575
View details for Web of Science ID 000290585200055
View details for PubMedID 21385879
View details for PubMedCentralID PMC3093867
-
Mutagenesis of Varicella-Zoster Virus Glycoprotein I (gI) Identifies a Cysteine Residue Critical for gE/gI Heterodimer Formation, gI Structure, and Virulence in Skin Cells
JOURNAL OF VIROLOGY
2011; 85 (9): 4095-4110
Abstract
Varicella-zoster virus (VZV) is the alphaherpesvirus that causes chicken pox (varicella) and shingles (zoster). The two VZV glycoproteins gE and gI form a heterodimer that mediates efficient cell-to-cell spread. Deletion of gI yields a small-plaque-phenotype virus, ΔgI virus, which is avirulent in human skin using the xenograft model of VZV pathogenesis. In the present study, 10 mutant viruses were generated to determine which residues were required for the typical function of gI. Three phosphorylation sites in the cytoplasmic domain of gI were not required for VZV virulence in vivo. Two deletion mutants mapped a gE binding region in gI to residues 105 to 125. A glycosylation site, N116, in this region did not affect virulence. Substitution of four cysteine residues highly conserved in the Alphaherpesvirinae established that C95 is required for gE/gI heterodimer formation. The C95A and Δ105-125 (with residues 105 to 125 deleted) viruses had small-plaque phenotypes with reduced replication kinetics in vitro similar to those of the ΔgI virus. The Δ105-125 virus was avirulent for human skin in vivo. In contrast, the C95A mutant replicated in vivo but with significantly reduced kinetics compared to those of the wild-type virus. In addition to abolished gE/gI heterodimer formation, gI from the C95A or the Δ105-125 mutant was not recognized by monoclonal antibodies that detect the canonical conformation of gI, demonstrating structural disruption of gI in these viruses. This alteration prevented gI incorporation into virus particles. Thus, residues C95 and 105 to 125 are critical for gI structure required for gE/gI heterodimer formation, virion incorporation, and ultimately, effective viral spread in human skin.
View details for DOI 10.1128/JVI.02596-10
View details for Web of Science ID 000289618600005
View details for PubMedID 21345964
View details for PubMedCentralID PMC3126246
-
Identification and functional characterization of the Varicella zoster virus ORF11 gene product
VIROLOGY
2011; 412 (1): 156-166
Abstract
The deletion of ORF11 severely impaired VZV infection of human skin xenografts. Here, we investigate the characteristics and functions of the ORF11 gene product. ORF11 is expressed as a 118kDa polypeptide in VZV-infected cells; the protein is present in the nucleus and cytoplasm and is incorporated into VZ virions. Although ORF11 had little effect in transactivating VZV gene promoters in transfection assays, deleting ORF11 from the virus was associated with reduced expression of immediate early proteins IE4, IE62 and IE63, and the major glycoprotein, gE. ORF11 was identified as an RNA binding protein and its RNA binding domain was defined. However, disrupting the ORF11 RNA binding domain did not affect skin infection, indicating that RNA binding capacity, conserved among the alphaherpesviruses homologues, is not essential while the contribution of ORF11 to the expression of the IE proteins and gE may be required for VZV pathogenesis in skin in vivo.
View details for DOI 10.1016/j.virol.2010.12.055
View details for Web of Science ID 000288778200018
View details for PubMedID 21276599
View details for PubMedCentralID PMC3068617
-
Varicella Zoster Disease of the Central Nervous System: Epidemiological, Clinical, and Laboratory Features 10 Years after the Introduction of the Varicella Vaccine
JOURNAL OF INFECTIOUS DISEASES
2011; 203 (3): 316-323
Abstract
Since the introduction of live attenuated varicella zoster virus (VZV) vaccine in 1995 there has been a significant reduction in varicella incidence and its associated complications, but the impact on VZV-associated central nervous system (CNS) disease has not been assessed.In this descriptive study we evaluated patients referred to the California Encephalitis Project from 1998 to 2009 with VZV PCR-positive cerebrospinal fluid (CSF). Epidemiological, clinical, and laboratory data were collected using a standardized case form. Specimens were genotyped using multi-single nucleotide polymorphism (SNP) analysis.Twenty-six specimens were genotyped from patients 12-85 years of age (median, 46 years). Clinical presentations included meningitis (50%), encephalitis (42%), and acute disseminated encephalomyelitis (ADEM) (8%). Only 11 patients (42%) had a concomitant herpes zoster rash. Genotype analysis identified 20 European Group (Clade1, Clade 3) strains; 4 Asian (Clade 2) strains, and 2 Mosaic Group (Clade 4, Clade VI) strains. One specimen was recognized as vaccine strain by identifying vaccine-associated SNPs.VZV continues to be associated with CNS disease, with meningitis being the most frequent clinical presentation. CNS VZV disease often presented without accompanying zoster rash. Sequencing data revealed multiple genotypes, including 1 vaccine strain detected in the CSF of a young patient with meningitis.
View details for DOI 10.1093/infdis/jiq066
View details for Web of Science ID 000286611800006
View details for PubMedID 21177308
View details for PubMedCentralID PMC3071104
-
Herpes simplex virus-1 induces expression of a novel MxA isoform that enhances viral replication
IMMUNOLOGY AND CELL BIOLOGY
2011; 89 (2): 173-182
Abstract
MxA is an antiviral protein induced by interferon (IFN)-α/β that is known to inhibit the replication of many RNA viruses. In these experiments, the 76-kDa MxA protein expressed in IFN-α-treated cells was shown to have antiviral activity against herpes simplex virus-1 (HSV-1), a human DNA virus. However, MxA was expressed as a 56-kDa protein in HSV-1-infected cells in the absence of IFN-α. This previously unrecognized MxA isoform was produced from an alternatively spliced MxA transcript that had a deletion of Exons 14-16 and a frame shift altering the C-terminus. The variant MxA (varMxA) isoform was associated with HSV-1 regulatory proteins and virions in nuclear replication compartments. varMxA expression enhanced HSV-1 infection as shown by a reduction in infectious virus titers from cells in which MxA had been inhibited by RNA interference and by an increase in HSV-1 titers when the 56-kDa varMxA was expressed constitutively. Thus, the human MxA gene encodes two MxA isoforms, which are expressed differentially depending on whether the stimulus is IFN-α or HSV-1. These findings show that alternative splicing of cellular mRNA can result in expression of a novel isoform of a host defense gene that supports instead of restricting viral infection.
View details for DOI 10.1038/icb.2010.83
View details for Web of Science ID 000287445400005
View details for PubMedID 20603636
-
Varicella-Zoster Virus Glycoprotein E Is a Critical Determinant of Virulence in the SCID Mouse-Human Model of Neuropathogenesis
JOURNAL OF VIROLOGY
2011; 85 (1): 98-111
Abstract
Varicella-zoster virus (VZV) is a neurotropic alphaherpesvirus. VZV infection of human dorsal root ganglion (DRG) xenografts in immunodeficient mice models the infection of sensory ganglia. We examined DRG infection with recombinant VZV (recombinant Oka [rOka]) and the following gE mutants: gEΔ27-90, gEΔCys, gE-AYRV, and gE-SSTT. gEΔ27-90, which lacks the gE domain that interacts with a putative receptor insulin-degrading enzyme (IDE), replicated as extensively as rOka, producing infectious virions and significant cytopathic effects within 14 days of inoculation. Since neural cells express IDE, the gE/IDE interaction was dispensable for VZV neurotropism. In contrast, gEΔCys, which lacks gE/gI heterodimer formation, was significantly impaired at early times postinfection; viral genome copy numbers increased slowly, and infectious virus production was not detected until day 28. Delayed replication was associated with impaired cell-cell spread in ganglia, similar to the phenotype of a gI deletion mutant (rOkaΔgI). However, at later time points, infection of satellite cells and other supportive nonneuronal cells resulted in extensive DRG tissue damage and cell loss such that cytopathic changes observed at day 70 were more severe than those for rOka-infected DRG. The replication of gE-AYRV, which is impaired for trans-Golgi network (TGN) localization, and the replication of gE-SSTT, which contains mutations in an acidic cluster, were equivalent to that of rOka, causing significant cytopathic effects and infectious virus production by day 14; genome copy numbers were equivalent to those of rOka. These experiments suggest that the gE interaction with cellular IDE, gE targeting to TGN sites of virion envelopment, and phosphorylation at SSTT are dispensable for VZV DRG infection, whereas the gE/gI interaction is critical for VZV neurovirulence.
View details for DOI 10.1128/JVI.01902-10
View details for Web of Science ID 000285095800008
View details for PubMedID 20962081
View details for PubMedCentralID PMC3014186
-
Varicella-zoster Virus Pathogenesis and Latency
ALPHAHERPESVIRUSES: MOLECULAR VIROLOGY
2011: 269–94
View details for Web of Science ID 000287717200016
-
Live Attenuated Vaccines: Influenza, Rotavirus and Varicella Zoster Virus
REPLICATING VACCINES: A NEW GENERATION
2011: 15–46
View details for DOI 10.1007/978-3-0346-0277-8_2
View details for Web of Science ID 000284509000002
-
Expression of Varicella-Zoster Virus Immediate-Early Regulatory Protein IE63 in Neurons of Latently Infected Human Sensory Ganglia
JOURNAL OF VIROLOGY
2010; 84 (7): 3421-3430
Abstract
Varicella-zoster virus (VZV) causes varicella and establishes latency in sensory nerve ganglia, but the characteristics of VZV latency are not well defined. Immunohistochemical detection of the VZV immediate-early 63 (IE63) protein in ganglion neurons has been described, but there are significant discrepancies in estimates of the frequency of IE63-positive neurons, varying from a rare event to abundant expression. We examined IE63 expression in cadaver ganglia using a high-potency rabbit anti-IE63 antibody and corresponding preimmune serum. Using standard immunohistochemical techniques, we evaluated 10 ganglia that contained VZV DNA from seven individuals. These experiments showed that neuronal pigments were a confounding variable; however, by examining sections coded to prevent investigator bias and applying statistical analysis, we determined that IE63 protein, if present, is in a very small proportion of neurons (<2.8%). To refine estimates of IE63 protein abundance, we modified our protocol by incorporating a biological stain to exclude the pigment signal and evaluated 27 ganglia from 18 individuals. We identified IE63 protein in neurons within only one ganglion, in which VZV glycoprotein E and an immune cell infiltrate were also demonstrated. Antigen preservation was shown by detection of neuronal synaptophysin. These data provide evidence that the expression of IE63 protein, which has been referred to as a latency-associated protein, is rare. Refining estimates of VZV protein expression in neurons is important for developing a hypothesis about the mechanisms by which VZV latency may be maintained.
View details for DOI 10.1128/JVI.02416-09
View details for PubMedID 20106930
View details for PubMedCentralID PMC2838126
-
Impact of Varicella-Zoster Virus on Dendritic Cell Subsets in Human Skin during Natural Infection
JOURNAL OF VIROLOGY
2010; 84 (8): 4060-4072
Abstract
Varicella-zoster virus (VZV) causes varicella and herpes zoster, diseases characterized by distinct cutaneous rashes. Dendritic cells (DC) are essential for inducing antiviral immune responses; however, the contribution of DC subsets to immune control during natural cutaneous VZV infection has not been investigated. Immunostaining showed that compared to normal skin, the proportion of cells expressing DC-SIGN (a dermal DC marker) or DC-LAMP and CD83 (mature DC markers) were not significantly altered in infected skin. In contrast, the frequency of Langerhans cells was significantly decreased in VZV-infected skin, whereas there was an influx of plasmacytoid DC, a potent secretor of type I interferon (IFN). Langerhans cells and plasmacytoid DC in infected skin were closely associated with VZV antigen-positive cells, and some Langerhans cells and plasmacytoid DC were VZV antigen positive. To extend these in vivo observations, both plasmacytoid DC (PDC) isolated from human blood and Langerhans cells derived from MUTZ-3 cells were shown to be permissive to VZV infection. In VZV-infected PDC cultures, significant induction of alpha IFN (IFN-alpha) did not occur, indicating the VZV inhibits the capacity of PDC to induce expression of this host defense cytokine. This study defines changes in the response of DC which occur during cutaneous VZV infection and implicates infection of DC subtypes in VZV pathogenesis.
View details for DOI 10.1128/JVI.01450-09
View details for Web of Science ID 000275781500031
View details for PubMedID 20130046
View details for PubMedCentralID PMC2849518
-
Functions of the unique N-terminal region of glycoprotein E in the pathogenesis of varicella-zoster virus infection
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2010; 107 (1): 282-287
Abstract
Varicella-zoster virus (VZV) is an alphaherpesvirus that infects skin, lymphocytes, and sensory ganglia. VZV glycoprotein E (gE) has a unique N-terminal region (aa1-188), which is required for replication and includes domains involved in secondary envelopment, efficient cell-cell spread, and skin infection in vivo. The nonconserved N-terminal region also mediates binding to the insulin-degrading enzyme (IDE), which is proposed to be a VZV receptor. Using viral mutagenesis to make the recombinant rOka-DeltaP27-G90, we showed that amino acids in this region are required for gE/IDE binding in infected cells; this deletion reduced cell-cell spread in vitro and skin infection in vivo. However, a gE point mutation, linker insertions, and partial deletions in the aa27-90 region, and deletion of a large portion of the unique N-terminal region, aa52-187, had similar or more severe effects on VZV replication in vitro and in vivo without disrupting the gE/IDE interaction. VZV replication in T cells in vivo was not impaired by deletion of gE aa27-90, suggesting that these gE residues are not essential for VZV T cell tropism. However, the rOka-DeltaY51-P187 mutant failed to replicate in T cell xenografts as well as skin in vivo. VZV tropism for T cells and skin, which is necessary for its life cycle in the human host, requires this nonconserved region of the N-terminal region of VZV gE.
View details for DOI 10.1073/pnas.0912373107
View details for Web of Science ID 000273559200049
View details for PubMedID 19966293
View details for PubMedCentralID PMC2806775
-
Varicella-Zoster Virus Neurotropism in SCID Mouse-Human Dorsal Root Ganglia Xenografts
VARICELLA-ZOSTER VIRUS
2010; 342: 255-276
Abstract
Varicella-zoster virus (VZV) is a neurotropic human alphaherpesvirus and the causative agent of varicella and herpes zoster. VZV reactivation from latency in sensory nerve ganglia is a direct consequence of VZV neurotropism. Investigation of VZV neuropathogenesis by infection of human dorsal root ganglion xenografts in immunocompromised (SCID) mice has provided a novel system in which to examine VZV neurotropism. Experimental infection with recombinant VZV mutants with targeted deletions or mutations of specific genes or regulatory elements provides an opportunity to assess gene candidates that may mediate neurotropism and neurovirulence. The SCID mouse-human DRG xenograft model may aid in the development of clinical strategies in the management of herpes zoster as well as in the development of "second generation" neuroattenuated vaccines.
View details for DOI 10.1007/82_2009_8
View details for Web of Science ID 000282104800016
View details for PubMedID 20225014
-
Evaluation of a Site-Specific Risk Assessment for the Department of Homeland Security's Planned National Bio- and Agro-Defense Facility in Manhattan, Kansas SUMMARY
EVALUATION OF A SITE-SPECIFIC RISK ASSESSMENT FOR THE DEPARTMENT OF HOMELAND SECURITY'S PLANNED NATIONAL BIO- AND AGRO-DEFENSE FACILITY IN MANHATTAN, KANSAS
2010: 93–122
View details for Web of Science ID 000356268800007
-
Anti-Glycoprotein H Antibody Impairs the Pathogenicity of Varicella-Zoster Virus in Skin Xenografts in the SCID Mouse Model
JOURNAL OF VIROLOGY
2010; 84 (1): 141-152
Abstract
Varicella-zoster virus (VZV) infection is usually mild in healthy individuals but can cause severe disease in immunocompromised patients. Prophylaxis with varicella-zoster immunoglobulin can reduce the severity of VZV if given shortly after exposure. Glycoprotein H (gH) is a highly conserved herpesvirus protein with functions in virus entry and cell-cell spread and is a target of neutralizing antibodies. The anti-gH monoclonal antibody (MAb) 206 neutralizes VZV in vitro. To determine the requirement for gH in VZV pathogenesis in vivo, MAb 206 was administered to SCID mice with human skin xenografts inoculated with VZV. Anti-gH antibody given at 6 h postinfection significantly reduced the frequency of skin xenograft infection by 42%. Virus titers, genome copies, and lesion size were decreased in xenografts that became infected. In contrast, administering anti-gH antibody at 4 days postinfection suppressed VZV replication but did not reduce the frequency of infection. The neutralizing anti-gH MAb 206 blocked virus entry, cell fusion, or both in skin in vivo. In vitro, MAb 206 bound to plasma membranes and to surface virus particles. Antibody was internalized into vacuoles within infected cells, associated with intracellular virus particles, and colocalized with markers for early endosomes and multivesicular bodies but not the trans-Golgi network. MAb 206 blocked spread, altered intracellular trafficking of gH, and bound to surface VZV particles, which might facilitate their uptake and targeting for degradation. As a consequence, antibody interference with gH function would likely prevent or significantly reduce VZV replication in skin during primary or recurrent infection.
View details for DOI 10.1128/JVI.01338-09
View details for Web of Science ID 000272564300013
View details for PubMedID 19828615
View details for PubMedCentralID PMC2798403
-
Varicella-Zoster Virus T Cell Tropism and the Pathogenesis of Skin Infection
VARICELLA-ZOSTER VIRUS
2010; 342: 189-209
Abstract
Varicella-zoster virus (VZV) is a medically important human alphaherpesvirus that causes varicella and zoster. VZV initiates primary infection by inoculation of the respiratory mucosa. In the course of primary infection, VZV establishes a life-long persistence in sensory ganglia; VZV reactivation from latency may result in zoster in healthy and immunocompromised patients. The VZV genome has at least 70 known or predicted open reading frames (ORFs), but understanding how these gene products function in virulence is difficult because VZV is a highly human-specific pathogen. We have addressed this obstacle by investigating VZV infection of human tissue xenografts in the severe combined immunodeficiency mouse model. In studies relevant to the pathogenesis of primary VZV infection, we have examined VZV infection of human T cell (thymus/liver) and skin xenografts. This work supports a new paradigm for VZV pathogenesis in which VZV T cell tropism provides a mechanism for delivering the virus to skin. We have also shown that VZV-infected T cells transfer VZV to neurons in sensory ganglia. The construction of infectious VZV recombinants that have deletions or targeted mutations of viral genes or their promoters and the evaluation of VZV mutants in T cell and skin xenografts has revealed determinants of VZV virulence that are important for T cell and skin tropism in vivo.
View details for DOI 10.1007/82_2010_29
View details for Web of Science ID 000282104800012
View details for PubMedID 20397071
-
Analysis of the Functions of Glycoproteins E and I and Their Promoters During VZV Replication In Vitro and in Skin and T-Cell Xenografts in the SCID Mouse Model of VZV Pathogenesis
VARICELLA-ZOSTER VIRUS
2010; 342: 129-146
Abstract
The two VZV glycoproteins, gE and gI, are encoded by genes that are designated open reading frames, ORF67 and ORF68, located in the short unique region of the VZV genome. These proteins have homologs in the other alphaherpesviruses. Like their homologues, VZV gE and gI exhibit prominent co-localization in infected cells and form heterodimers. However, VZV gE is much larger than its homologues because it has a unique N-terminal domain, consisting of 188 amino acids that are not present in these other gene products. VZV gE also differs from the related gE proteins, in that it is essential for viral replication. Targeted mutations of gE that are compatible with VZV replication in cultured cells have varying phenotypes in skin and T-cell xenografts in the SCID mouse model of VZV pathogenesis in vivo. While gI is dispensable for growth in cultured cells in vitro, this glycoprotein is essential for VZV infection of differentiated human skin and T cells in vivo. The promoter regions of gE and gI are regulated by the cellular transactivator, specificity protein factor 1 (Sp1) in combination with the major VZV transactivator in reporter construct experiments and some Sp1 promoter elements are important for VZV virulence in vivo. Further analysis of VZV gE and gI functions and their interactions with other viral and host cell proteins are important areas for studies of VZV replication and pathogenesis.
View details for DOI 10.1007/82_2009_1
View details for Web of Science ID 000282104800008
View details for PubMedID 20186616
-
Age-Related Increase in the Frequency of CD4(+) T Cells That Produce Interferon-gamma in Response to Staphylococcal Enterotoxin B during Childhood
JOURNAL OF INFECTIOUS DISEASES
2009; 200 (12): 1921-1927
Abstract
The susceptibility of infants to infections is well defined clinically, and immunologic abnormalities have been described. Immune maturation is complex, however, and the interval during which changes occur during childhood has not been identified.To assess age-related differences in the CD4(+) T cell responses, we evaluated the frequency of CD4(+) T cells that produced interferon (IFN) gamma in response to staphylococcal enterotoxin B (SEB) stimulation in 382 healthy infants and children (2 months to 11 years of age) and 66 adults. Flow cytometry was used to assess SEB-induced CD69 and CD40 ligand (CD40-L) expression and IFN-gamma production by CD4(+) and CD45RO(+)CD4(+) T cells.CD69 and CD40-L expression by CD4(+) and CD45RO(+)CD4(+) T cells were similar to adult levels from infancy, but the frequency of activated T cells that produced IFN-gamma remained lower than adult responses until children were 10 years of age.These observations indicate that the IFN-gamma response of CD4(+) T cells to SEB remains limited for a much longer interval than was reported elsewhere, extending to the second decade of life. Observed differences in CD45RO(+)CD4(+) T cell function indicate that CD4(+) T cells with the same phenotypes do not possess equivalent functional capabilities.
View details for DOI 10.1086/648375
View details for Web of Science ID 000271874000016
View details for PubMedID 19909079
-
Mutagenesis of Varicella-Zoster Virus Glycoprotein B: Putative Fusion Loop Residues Are Essential for Viral Replication, and the Furin Cleavage Motif Contributes to Pathogenesis in Skin Tissue In Vivo
JOURNAL OF VIROLOGY
2009; 83 (15): 7495-7506
Abstract
Glycoprotein B (gB), the most conserved protein in the family Herpesviridae, is essential for the fusion of viral and cellular membranes. Information about varicella-zoster virus (VZV) gB is limited, but homology modeling showed that the structure of VZV gB was similar to that of herpes simplex virus (HSV) gB, including the putative fusion loops. In contrast to HSV gB, VZV gB had a furin recognition motif ([R]-X-[KR]-R-|-X, where | indicates the position at which the polypeptide is cleaved) at residues 491 to 494, thought to be required for gB cleavage into two polypeptides. To investigate their contribution, the putative primary fusion loop or the furin recognition motif was mutated in expression constructs and in the context of the VZV genome. Substitutions in the primary loop, W180G and Y185G, plus the deletion mutation Delta491RSRR494 and point mutation 491GSGG494 in the furin recognition motif did not affect gB expression or cellular localization in transfected cells. Infectious VZV was recovered from parental Oka (pOka)-bacterial artificial chromosomes that had either the Delta491RSRR494 or 491GSGG494 mutation but not the point mutations W180G and Y185G, demonstrating that residues in the primary loop of gB were essential but gB cleavage was not required for VZV replication in vitro. Virion morphology, protein localization, plaque size, and replication were unaffected for the pOka-gBDelta491RSRR494 or pOka-gB491GSGG494 virus compared to pOka in vitro. However, deletion of the furin recognition motif caused attenuation of VZV replication in human skin xenografts in vivo. This is the first evidence that cleavage of a herpesvirus fusion protein contributes to viral pathogenesis in vivo, as seen for fusion proteins in other virus families.
View details for DOI 10.1128/JVI.00400-09
View details for Web of Science ID 000267747400015
View details for PubMedID 19474103
View details for PubMedCentralID PMC2708640
-
Regulation of the ORF61 Promoter and ORF61 Functions in Varicella-Zoster Virus Replication and Pathogenesis
JOURNAL OF VIROLOGY
2009; 83 (15): 7560-7572
Abstract
Varicella-zoster virus (VZV) open reading frame 61 (ORF61) encodes a protein that transactivates viral and cellular promoters in transient-transfection assays and is the ortholog of herpes simplex virus ICP0. In this report, we mapped the ORF61 promoter and investigated its regulation by viral and cellular proteins in transient-expression experiments and by mutagenesis of the VZV genome (parent Oka strain). The 5' boundary of the minimal ORF61 promoter required for IE62 transactivation was mapped to position -95 relative to the mRNA start site, and three noncanonical GT-rich Sp1-binding sites were documented to occur within the region comprising positions -95 to -45. Contributions of the three Sp1-binding-site motifs, designated Sp1a, Sp1b, and Sp1c, to ORF61 expression and viral replication were varied despite their similar sequences. Two sites, Sp1a and Sp1c, functioned synergistically. When both sites were mutated in the pOka genome to produce pOka-61proDeltaSp1ac, the mutant virus expressed significantly less ORF61 protein. Using this mutant to investigate ORF61 functions resulted in reductions in the expression levels of IE proteins, viral kinases ORF47 and ORF66, and the major glycoprotein gE, with the most impact on gE. Virion morphogenesis appeared to be intact despite minimal ORF61 expression. Pretreating melanoma cells with sodium butyrate enhanced titers of pOka-61proDeltaSp1ac but not pOka, suggesting that ORF61 has a role in histone deacetylase inhibition. Growth of pOka-61proDeltaSp1ac was impaired in SCIDhu skin xenografts, indicating that the regulation of the ORF61 promoter by Sp1 family proteins is important for ORF61 expression in vivo and that ORF61 contributes to VZV virulence at skin sites of replication.
View details for DOI 10.1128/JVI.00118-09
View details for Web of Science ID 000267747400021
View details for PubMedID 19457996
View details for PubMedCentralID PMC2708633
-
Varicella in the fetus and newborn
SEMINARS IN FETAL & NEONATAL MEDICINE
2009; 14 (4): 209-217
Abstract
Varicella (chickenpox) in pregnancy is unusual because most women of childbearing age are immune. It can, however, cause significant morbidity for the pregnant woman and in rare cases cause congenital varicella syndrome. The incidence of congenital varicella syndrome after maternal varicella during the first two trimesters is <1% across multiple cohort studies. Maternal infection in the third trimester is not associated with congenital varicella syndrome, but the infant may develop herpes zoster during the first one or two years. Maternal infection just before or after delivery presents a high risk for disseminated varicella in the infant. Serious infection can be prevented with passive antibody prophylaxis and antiviral therapy. Maternal herpes zoster does not result in adverse fetal or neonatal outcomes.
View details for DOI 10.1016/j.siny.2008.11.008
View details for Web of Science ID 000267631400006
View details for PubMedID 19097954
-
The Replication Cycle of Varicella-Zoster Virus: Analysis of the Kinetics of Viral Protein Expression, Genome Synthesis, and Virion Assembly at the Single-Cell Level
JOURNAL OF VIROLOGY
2009; 83 (8): 3904-3918
Abstract
Varicella-zoster virus (VZV) is a human alphaherpesvirus that is highly cell associated in cell culture. Because cell-free virus yields are too low to permit the synchronous infections needed for time-resolved analyses, information is lacking about the sequence of events during the VZV replication cycle. To address this challenge, we differentially labeled VZV-infected inoculum cells (input) and uninfected (output) cells with fluorescent cell dyes or endocytosed nanogold particles and evaluated newly infected cells by confocal immunofluorescence or electron microscopy (EM) at the single-cell level at defined intervals. We demonstrated the spatiotemporal expression of six major VZV proteins, ORF61, IE62, IE63, ORF29, ORF23, and gE, representing all putative kinetic classes, for the first time. Newly synthesized ORF61, as well as IE62, the major VZV transactivator, appeared within 1 h, and they were targeted to different subnuclear compartments. The formation of VZV DNA replication compartments started between 4 and 6 h, involved recruitment of ORF29 to putative IE62 prereplication sites, and resulted in large globular nuclear compartments where newly synthesized viral DNA accumulated. Although considered a late protein, gE accumulated in the Golgi compartment at as early as 4 h. ORF23 capsid protein was present at 9 h. The assembly of viral nucleocapsids and mature enveloped VZ virions was detected by 9 to 12 h by time-resolved EM. Although syncytium formation is a hallmark of VZV infection, infection of neighboring cells did not require cell-cell fusion; its occurrence from 9 h is likely to amplify VZV replication. Our results define the productive cycle of VZV infection in a single cell as occurring in 9 to 12 h.
View details for DOI 10.1128/JVI.02137-08
View details for Web of Science ID 000264327300046
View details for PubMedID 19193797
View details for PubMedCentralID PMC2663235
-
One Step Closer to a CMV Vaccine
NEW ENGLAND JOURNAL OF MEDICINE
2009; 360 (12): 1250-1252
View details for Web of Science ID 000264283400013
View details for PubMedID 19297578
-
Deletion of the first cysteine-rich region of the varicella-zoster virus glycoprotein E ectodomain abolishes the gE and gI interaction and differentially affects cell-cell spread and viral entry.
Journal of virology
2009; 83 (1): 228-240
Abstract
Varicella-zoster virus (VZV) glycoprotein E (gE) is the most abundant glycoprotein in infected cells and, in contrast to those of other alphaherpesviruses, is essential for viral replication. The gE ectodomain contains a unique N-terminal region required for viral replication, cell-cell spread, and secondary envelopment; this region also binds to the insulin-degrading enzyme (IDE), a proposed VZV receptor. To identify new functional domains of the gE ectodomain, the effect of mutagenesis of the first cysteine-rich region of the gE ectodomain (amino acids 208 to 236) was assessed using VZV cosmids. Deletion of this region was compatible with VZV replication in vitro, but cell-cell spread of the rOka-DeltaCys mutant was reduced significantly. Deletion of the cysteine-rich region abolished the binding of the mutant gE to gI but not to IDE. Preventing gE binding to gI altered the pattern of gE expression at the plasma membrane of infected cells and the posttranslational maturation of gI and its incorporation into viral particles. In contrast, deletion of the first cysteine-rich region did not affect viral entry into human tonsil T cells in vitro or into melanoma cells infected with cell-free VZV. These experiments demonstrate that gE/gI heterodimer formation is essential for efficient cell-cell spread and incorporation of gI into viral particles but that it is dispensable for infectious varicella-zoster virion formation and entry into target cells. Blocking gE binding to gI resulted in severe impairment of VZV infection of human skin xenografts in SCIDhu mice in vivo, documenting the importance of cell fusion mediated by this complex for VZV virulence in skin.
View details for DOI 10.1128/JVI.00913-08
View details for PubMedID 18945783
View details for PubMedCentralID PMC2612333
-
Development of recombinant varicella-zoster viruses expressing luciferase fusion proteins for live in vivo imaging in human skin and dorsal root ganglia xenografts
JOURNAL OF VIROLOGICAL METHODS
2008; 154 (1-2): 182-193
Abstract
Varicella-zoster virus (VZV) is a host specific human pathogen that has been studied using human xenografts in SCID mice. Live whole-animal imaging is an emerging technique to measure protein expression in vivo using luminescence. Currently, it has only been possible to determine VZV protein expression in xenografts postmortem. Therefore, to measure immediate early (IE63) and late (glycoprotein E [gE]) protein expression in vivo viruses expressing IE63 or gE as luciferase fusion proteins were generated. Viable recombinant viruses pOka-63-luciferase and pOka-63/70-luciferase, which had luciferase genes fused to ORF63 and its duplicate ORF70, or pOka-gE-CBR were recovered that expressed IE63 or gE as fusion proteins and generated luminescent plaques. In contrast to pOka-63/70-luciferase viruses, the luciferase gene was rapidly lost in vitro when fused to a single copy of ORF63 or ORF68. IE63 expression was successfully measured in human skin and dorsal root ganglia xenografts infected with the genomically stable pOka-63/70-luciferase viruses. The progress of VZV infection in dorsal root ganglia xenografts was delayed in valacyclovir treated mice but followed a similar trend in untreated mice when the antiviral was withdrawn 28 days post-inoculation. Thus, IE63-luciferase fusion proteins were effective for investigating VZV infection and antiviral activity in human xenografts.
View details for DOI 10.1016/j.jviromet.2008.07.033
View details for Web of Science ID 000261838800026
View details for PubMedID 18761377
View details for PubMedCentralID PMC2657092
-
Functions of Varicella-Zoster Virus ORF23 Capsid Protein in Viral Replication and the Pathogenesis of Skin Infection
JOURNAL OF VIROLOGY
2008; 82 (20): 10231-10246
Abstract
The assembly of herpesvirus capsids is a complex process involving interactions of multiple proteins in the cytoplasm and in the nucleus. Based on comparative genome analyses, varicella-zoster virus (VZV) open reading frame 23 (ORF23) encodes a conserved capsid protein, referred to as VP26 (UL35) in other alphaherpesviruses. Mutagenesis using a VZV bacterial artificial chromosome system showed that ORF23 was dispensable for replication in vitro. However, the absence of ORF23 disrupted capsid assembly in a melanoma cell line. Expression of ORF23 as a red fluorescent protein (RFP) fusion protein appeared to have a dominant negative effect on replication that was rescued by ORF23 expression from a nonnative site in the VZV genome. In contrast to its VP26 homolog, ORF23 has an intrinsic nuclear localization capacity that was mapped to an SRSRVV motif at residues 229 to 234 in the extreme C terminus of ORF23. In addition, coexpression with ORF23 resulted in nuclear import of the major capsid protein, ORF40. VZV ORF33.5 also translocated ORF40, which may provide a redundant mechanism in vitro but appears insufficient to overcome the dominant negative effect of the monomeric RFP-ORF23 (mRFP23) fusion protein. ORF23 was required for VZV infection of human skin xenografts, indicating that ORF33.5 does not compensate for lack of ORF23 in vivo. These observations suggest a model of VZV capsid assembly in which nuclear transport of the major capsid protein and associated proteins requires ORF23 during VZV replication in the human host. If so, ORF23 expression could be a target for a novel antiviral drug against VZV.
View details for DOI 10.1128/JVI.01890-07
View details for Web of Science ID 000260109100039
View details for PubMedID 18684828
View details for PubMedCentralID PMC2566272
-
Influence of Prior Influenza Vaccination on Antibody and B-Cell Responses
PLOS ONE
2008; 3 (8)
Abstract
Currently two vaccines, trivalent inactivated influenza vaccine (TIV) and live attenuated influenza vaccine (LAIV), are licensed in the USA. Despite previous studies on immune responses induced by these two vaccines, a comparative study of the influence of prior influenza vaccination on serum antibody and B-cell responses to new LAIV or TIV vaccination has not been reported. During the 2005/6 influenza season, we quantified the serum antibody and B-cell responses to LAIV or TIV in adults with differing influenza vaccination histories in the prior year: LAIV, TIV, or neither. Blood samples were collected on days 0, 7-9 and 21-35 after immunization and used for serum HAI assay and B-cell assays. Total and influenza-specific circulating IgG and IgA antibody secreting cells (ASC) in PBMC were detected by direct ELISPOT assay. Memory B cells were also tested by ELISPOT after polyclonal stimulation of PBMC in vitro. Serum antibody, effector, and memory B-cell responses were greater in TIV recipients than LAIV recipients. Prior year TIV recipients had significantly higher baseline HAI titers, but lower HAI response after vaccination with either TIV or LAIV, and lower IgA ASC response after vaccination with TIV than prior year LAIV or no vaccination recipients. Lower levels of baseline HAI titer were associated with a greater fold-increase of HAI titer and ASC number after vaccination, which also differed by type of vaccine. Our findings suggest that the type of vaccine received in the prior year affects the serum antibody and the B-cell responses to subsequent vaccination. In particular, prior year TIV vaccination is associated with sustained higher HAI titer one year later but lower antibody response to new LAIV or TIV vaccination, and a lower effector B-cell response to new TIV but not LAIV vaccination.
View details for DOI 10.1371/journal.pone.0002975
View details for Web of Science ID 000264420900002
View details for PubMedID 18714352
View details for PubMedCentralID PMC2500171
-
Baseline Levels of Influenza-Specific CD4 Memory T-Cells Affect T-Cell Responses to Influenza Vaccines
PLOS ONE
2008; 3 (7)
Abstract
Factors affecting immune responses to influenza vaccines have not been studied systematically. We hypothesized that T-cell and antibody responses to the vaccines are functions of pre-existing host immunity against influenza antigens.During the 2004 and 2005 influenza seasons, we have collected data on cellular and humoral immune reactivity to influenza virus in blood samples collected before and after immunization with inactivated or live attenuated influenza vaccines in healthy children and adults. We first used cross-validated lasso regression on the 2004 dataset to identify a group of candidate baseline correlates with T-cell and antibody responses to vaccines, defined as fold-increase in influenza-specific T-cells and serum HAI titer after vaccination. The following baseline parameters were examined: percentages of influenza-reactive IFN-gamma(+) cells in T and NK cell subsets, percentages of influenza-specific memory B-cells, HAI titer, age, and type of vaccine. The candidate baseline correlates were then tested with the independent 2005 dataset. Baseline percentage of influenza-specific IFN-gamma(+) CD4 T-cells was identified as a significant correlate of CD4 and CD8 T-cell responses, with lower baseline levels associated with larger T-cell responses. Baseline HAI titer and vaccine type were identified as significant correlates for HAI response, with lower baseline levels and the inactivated vaccine associated with larger HAI responses. Previously we reported that baseline levels of CD56(dim) NK reactivity against influenza virus inversely correlated with the immediate T-cell response to vaccination, and that NK reactivity induced by influenza virus depended on IL-2 produced by influenza-specific memory T-cells. Taken together these results suggest a novel mechanism for the homeostasis of virus-specific T-cells, which involves interaction between memory helper T-cells, CD56(dim) NK and DC.These results demonstrate that assessment of baseline biomarkers may predict immunologic outcome of influenza vaccination and may reveal some of the mechanisms responsible for variable immune responses following vaccination and natural infection.
View details for DOI 10.1371/journal.pone.0002574
View details for Web of Science ID 000263288200039
View details for PubMedID 18596908
View details for PubMedCentralID PMC2440350
-
Immune responses to mumps vaccine in adults who were vaccinated in childhood
Annual Meeting of the Pediatric-Academic-Societies/Society-of-Pediatric-Research
UNIV CHICAGO PRESS. 2008: 1669–75
Abstract
In a mumps outbreak in the United States, many infected individuals were adults who had received 2 doses of mumps vaccine. The persistence of cellular immunity to mumps vaccine has not been defined.This was an observational, nonrandomized cohort study evaluating cell-mediated and humoral immunity to mumps in 10 vaccinated and 10 naturally immune adults. Mumps-specific T cell activation and interferon (IFN)-gamma production were measured using lymphoproliferative and flow cytometry assays, and mumps immunoglobulin (Ig) G was measured using enzyme-linked immunosorbent assay.T cell immunity to mumps was high in both groups; 70% of vaccinated and 80% of naturally immune individuals had a positive (> or =3) stimulation index (SI) (P = 1.0). The mean percentages of mumps-specific CD4+ T cells that expressed CD69 and produced IFN-gamma were equivalent in the 2 groups: 0.06% and 0.12%, respectively (P = .11). The mean SIs in the groups were also equivalent, although IFN-gamma concentrations from cultures stimulated with mumps antigen were higher in naturally immune adults than in vaccinated adults (P < or = .01). All adults were positive for mumps IgG.T and B cell immunity to mumps was detected in adults at least 10 years after immunization. Except for IFN-gamma release, responses in vaccinated adults paralleled those observed in naturally immune individuals.
View details for DOI 10.1086/588195
View details for Web of Science ID 000256315300006
View details for PubMedID 18419345
View details for PubMedCentralID PMC2561204
-
Effects of interleukin-12 and interleukin-15 on measles-specific T-cell responses in vaccinated infants
VIRAL IMMUNOLOGY
2008; 21 (2): 163-172
Abstract
Understanding the infant host response to measles vaccination is important because of their increased mortality from measles and the need to provide effective protection during the first year of life. Measles-specific T and B-cell responses are lower in infants after measles vaccination than in adults. To define potential mechanisms, we investigated age-related differences in measles-specific T-cell proliferation, CD40-L expression, and IFN-gamma production after measles immunization, and the effects of rhIL-12 and rhIL-15 on these responses. Measles-specific T-cell proliferation and mean IFN-gamma release from infant PBMCs were significantly lower when compared with responses of vaccinated children and adults. Infant responses increased to ranges observed in children and adults when both rhIL-12 and rhIL-15 were added to PBMC cultures. Furthermore, a significant rise in T-cell proliferation and IFN-gamma release was observed when infant PBMCs were stimulated with measles antigen in the presence of rhIL-12 and rhIL-15 compared to measles antigen alone. CD40-L expression by infant and adult T cells stimulated with measles antigen was comparable, but fewer infant CD40-L(+) T cells expressed IFN-gamma. These observations suggest that lower measles-specific T-cell immune responses elicited by measles vaccine in infants may be due to diminished levels of key cytokines.
View details for DOI 10.1089/vim.2007.0113
View details for Web of Science ID 000257494700008
View details for PubMedID 18419254
View details for PubMedCentralID PMC2599809
-
Functions of the ORF9-to-ORF12 gene cluster in varicella-zoster virus replication and in the pathogenesis of skin infection
JOURNAL OF VIROLOGY
2008; 82 (12): 5825-5834
Abstract
The gene cluster composed of varicella-zoster virus (VZV) open reading frame 9 (ORF9) to ORF12 encodes four putative tegument proteins and is highly conserved in most alphaherpesviruses. In these experiments, the genes within this cluster were deleted from the VZV parent Oka (POKA) individually or in combination, and the consequences for VZV replication were evaluated with cultured cells in vitro and with human skin xenografts in SCID mice in vivo. As has been reported for ORF10, ORF11 and ORF12 were dispensable for VZV replication in melanoma and human embryonic fibroblast cells. In contrast, deletion of ORF9 was incompatible with the recovery of infectious virus. ORF9 localized to the virion tegument and formed complexes with glycoprotein E, which is an essential protein, in VZV-infected cells. Recombinants lacking ORF10 and ORF11 (POKADelta10/11), ORF11 and ORF12 (POKADelta11/12), or ORF10, ORF11 and ORF12 (POKADelta10/11/12) were viable in cultured cells. Their growth kinetics did not differ from those of POKA, and nucleocapsid formation and virion assembly were not disrupted. In addition, these deletion mutants showed no differences compared to POKA in infectivity levels for primary human tonsil T cells. Deletion of ORF12 had no effect on skin infection, whereas replication of POKADelta11, POKADelta10/11, and POKADelta11/12 was severely reduced, and no virus was recovered from skin xenografts inoculated with POKADelta10/11/12. These results indicate that with the exception of ORF9, the individual genes within the ORF9-to-ORF12 gene cluster are dispensable and can be deleted simultaneously without any apparent effect on VZV replication in vitro but that the ORF10-to-ORF12 cluster is essential for VZV virulence in skin in vivo.
View details for DOI 10.1128/JVI.00303-08
View details for Web of Science ID 000256453600015
View details for PubMedID 18400847
View details for PubMedCentralID PMC2395146
-
Primary vaccine failure after 1 dose of varicella vaccine in healthy children
44th Annual Meeting of the Infectious-Diseases-Society-of-America
UNIV CHICAGO PRESS. 2008: 944–49
Abstract
Universal immunization of young children with 1 dose of varicella vaccine was recommended in the United States in 1995, and it has significantly decreased the incidence of chickenpox. Outbreaks of varicella, however, are reported among vaccinated children. Although vaccine effectiveness has usually been 85%, rates as low as 44% have been observed. Whether this is from primary or secondary vaccine failure-or both-is unclear. We tested serum samples from 148 healthy children immunized against varicella in New York, Tennessee, and California to determine their seroconversion rates, before and after 1 dose of Merck/Oka varicella vaccine. The median age at vaccination was 12.5 months; postvaccination serum samples were obtained on average 4 months later. Serum was tested for antibodies against varicella-zoster virus (VZV) by use of the previously validated sensitive and specific fluorescent antibody to membrane antigen (FAMA) assay. Of 148 healthy child vaccinees, 113 (76%) seroconverted, and 24% had no detectable VZV FAMA antibodies. Our data contrast with reported seroconversion rates of 86%-96% by other VZV antibody tests and suggest that many cases of varicella in immunized children are due to primary vaccine failure. A second dose of varicella vaccine is expected to increase seroconversion rates and vaccine effectiveness.
View details for DOI 10.1086/529043
View details for Web of Science ID 000254249500004
View details for PubMedID 18419532
View details for PubMedCentralID PMC2657090
-
A Novel Immune Evasion Mechanism by Human Alphaherpesviruses
FEDERATION AMER SOC EXP BIOL. 2008
View details for Web of Science ID 000208467805471
-
Mechanisms of varicella-zoster virus neuropathogenesis in human dorsal root ganglia
JOURNAL OF VIROLOGY
2008; 82 (8): 3971-3983
Abstract
Varicella-zoster virus (VZV) is a human alphaherpesvirus that infects sensory ganglia and reactivates from latency to cause herpes zoster. VZV replication was examined in human dorsal root ganglion (DRG) xenografts in mice with severe combined immunodeficiency using multiscale correlative immunofluorescence and electron microscopy. These experiments showed the presence of VZV genomic DNA, viral proteins, and virion production in both neurons and satellite cells within DRG. Furthermore, the multiscale analysis of VZV-host cell interactions revealed virus-induced cell-cell fusion and polykaryon formation between neurons and satellite cells during VZV replication in DRG in vivo. Satellite cell infection and polykaryon formation in neuron-satellite cell complexes provide mechanisms to amplify VZV entry into neuronal cell bodies, which is necessary for VZV transfer to skin in the affected dermatome during herpes zoster. These mechanisms of VZV neuropathogenesis help to account for the often severe neurologic consequences of herpes zoster.
View details for DOI 10.1128/JV1.02592-07
View details for Web of Science ID 000254721300016
View details for PubMedID 18256143
View details for PubMedCentralID PMC2292995
-
Phenotypic changes in influenza-specific CD8(+) T cells after immunization of children and adults with influenza vaccines
26th Annual Meeting of the American-Society-for-Virology
UNIV CHICAGO PRESS. 2008: 803–11
Abstract
The effect of trivalent inactivated influenza vaccine (TIV) or live attenuated influenza vaccine (LAIV) on the phenotypes of circulating influenza-specific CD8+ T cells was analyzed by interferon (IFN)-gamma flow cytometry and tetramer staining. In adults, the expression of the T cell differentiation marker CD27 on virus-specific CD8+ T cells decreased after LAIV but increased after TIV. In children, expression of the cytotoxicity molecule perforin in influenza-specific CD8+ T cells increased after TIV but not after LAIV. Among children aged 6 months to 4 years who had not been vaccinated previously and who received 2 doses of TIV, CD27 expression decreased after each dose, whereas perforin expression increased after the second dose. These findings indicate that the phenotypic changes of influenza-specific CD8+ T cells differ depending on the type of vaccine and the age of the vaccinee. These differences are potentially affected by the different routes of vaccination and pathways of antigen presentation for TIV and LAIV.
View details for DOI 10.1086/528804
View details for Web of Science ID 000253773900005
View details for PubMedID 18279048
-
Varicella vaccine in the United States: A decade of prevention and the way forward
JOURNAL OF INFECTIOUS DISEASES
2008; 197: S39-S40
View details for DOI 10.1086/522165
View details for Web of Science ID 000253773600001
View details for PubMedID 18419405
-
Humoral and cellular immunity to varicella-zoster virus: An overview
JOURNAL OF INFECTIOUS DISEASES
2008; 197: S58-S60
View details for DOI 10.1086/522123
View details for Web of Science ID 000253773600006
View details for PubMedID 18419410
-
The pathogenesis of varicella-zoster virus neurotropism and infection
NEUROTROPIC VIRAL INFECTIONS
2008: 225–50
View details for DOI 10.1017/CBO9780511541728.016
View details for Web of Science ID 000313454600016
-
Deletion of the First Cysteine-Rich Region of the Varicella-Zoster Virus Glycoprotein E Ectodomain Abolishes the gE and gI Interaction and Differentially Affects Cell-Cell Spread and Viral Entry
JOURNAL OF VIROLOGY
2008; 83 (1): 228-240
Abstract
Varicella-zoster virus (VZV) glycoprotein E (gE) is the most abundant glycoprotein in infected cells and, in contrast to those of other alphaherpesviruses, is essential for viral replication. The gE ectodomain contains a unique N-terminal region required for viral replication, cell-cell spread, and secondary envelopment; this region also binds to the insulin-degrading enzyme (IDE), a proposed VZV receptor. To identify new functional domains of the gE ectodomain, the effect of mutagenesis of the first cysteine-rich region of the gE ectodomain (amino acids 208 to 236) was assessed using VZV cosmids. Deletion of this region was compatible with VZV replication in vitro, but cell-cell spread of the rOka-DeltaCys mutant was reduced significantly. Deletion of the cysteine-rich region abolished the binding of the mutant gE to gI but not to IDE. Preventing gE binding to gI altered the pattern of gE expression at the plasma membrane of infected cells and the posttranslational maturation of gI and its incorporation into viral particles. In contrast, deletion of the first cysteine-rich region did not affect viral entry into human tonsil T cells in vitro or into melanoma cells infected with cell-free VZV. These experiments demonstrate that gE/gI heterodimer formation is essential for efficient cell-cell spread and incorporation of gI into viral particles but that it is dispensable for infectious varicella-zoster virion formation and entry into target cells. Blocking gE binding to gI resulted in severe impairment of VZV infection of human skin xenografts in SCIDhu mice in vivo, documenting the importance of cell fusion mediated by this complex for VZV virulence in skin.
View details for DOI 10.1128/JVI.00913-08
View details for Web of Science ID 000261559100022
View details for PubMedCentralID PMC2612333
-
A self-excisable infectious bacterial artificial chromosome clone of varicella-zoster virus allows analysis of the essential tegument protein encoded by ORF9
JOURNAL OF VIROLOGY
2007; 81 (23): 13200-13208
Abstract
In order to facilitate the generation of mutant viruses of varicella-zoster virus (VZV), the agent causing varicella (chicken pox) and herpes zoster (shingles), we generated a full-length infectious bacterial artificial chromosome (BAC) clone of the P-Oka strain. First, mini-F sequences were inserted into a preexisting VZV cosmid, and the SuperCos replicon was removed. Subsequently, mini-F-containing recombinant virus was generated from overlapping cosmid clones, and full-length VZV DNA recovered from the recombinant virus was established in Escherichia coli as an infectious BAC. An inverted duplication of VZV genomic sequences within the mini-F replicon resulted in markerless excision of vector sequences upon virus reconstitution in eukaryotic cells. Using the novel tool, the role in VZV replication of the major tegument protein encoded by ORF9 was investigated. A markerless point mutation introduced in the start codon by two-step en passant Red mutagenesis abrogated ORF9 expression and resulted in a dramatic growth defect that was not observed in a revertant virus. The essential nature of ORF9 for VZV replication was ultimately confirmed by restoration of the growth of the ORF9-deficient mutant virus using trans-complementation via baculovirus-mediated gene transfer.
View details for DOI 10.1128/JVI.01148-07
View details for Web of Science ID 000251330500050
View details for PubMedID 17913822
View details for PubMedCentralID PMC2169085
-
Age-dependent differences in IgG isotype and avidity induced by measles vaccine received during the first year of life
JOURNAL OF INFECTIOUS DISEASES
2007; 196 (9): 1339-1345
Abstract
Measles remains an important cause of death worldwide, and vaccinating individuals at an earlier age could lead to better control of the disease. However, persistence of maternal antibody and young age affect the quantity of vaccine-induced neutralizing antibody and may also affect antibody quality.Enzyme immunoassay was used to analyze measles virus-specific IgG levels, avidity maturation, and isotype changes, using serum samples from infants who received measles vaccine at 6 months of age and measles-mumps-rubella (MMR)-II at 12 months of age (n=26), measles vaccine at 9 months of age and measles-mumps-rubella (MMR)-II at 12 months of age (n=48), or only MMR-II at 12 months of age (n=27).The median IgG level was lower among infants with maternal antibody than among those without maternal antibody. Compared with median avidity indices for infants aged 12 months, median values were lower for 6-month-old infants with maternal antibody (P=.0001), 6-month-old infants without maternal antibody (P=.001), 9-month-old infants with maternal antibody (P=.03), and 9-month-old infants without maternal antibody (P=.006). The median IgG3 level was highest at 6 months of age. IgG1 was predominant at 12 months. Low avidity responses at 6 or 9 months of age did not hinder higher avidity responses or the switch to IgG1 after secondary vaccination. The 2-dose regimen did not augment the response, compared with the response in infants who received 1 dose at 12 months of age.Avidity and isotype maturation of measles vaccine-induced antibody are affected by age, providing insight into the ontogeny of the immune response to measles vaccine.
View details for DOI 10.1086/522519
View details for Web of Science ID 000250010800012
View details for PubMedID 17922398
-
Cellular and viral factors regulate, the varicella-zoster virus gE promoter during viral replication
JOURNAL OF VIROLOGY
2007; 81 (19): 10258-10267
Abstract
Varicella-zoster virus (VZV) glycoprotein E (gE) is essential for viral replication and is involved in cell-to-cell spread, secondary envelopment, and entry. We created a set of mutations in the gE promoter to investigate the role of viral and cellular transcriptional factors in regulation of the gE promoter. Deletion or point mutation of the two Sp1 sites in the gE promoter abolished Sp1 binding and IE62-mediated transactivation of the gE promoter in vitro. Incorporation of the deletion or the point mutations disrupting both of the Sp1 binding sites into the VZV genome was not compatible with viral replication. A point mutation altering the atypical Sp1 binding site was lethal, while altering the second site impaired VZV replication significantly, indicating functional differences between the two Sp1 binding sites. Deletions in the gE promoter that abolished putative binding sites for cellular transcriptional factors other than Sp1, identified by bioinformatics analysis, were inserted in the VZV genome. Replication of the viruses with mutations of the gE promoter did not differ from control recombinants in melanoma cells or primary human tonsil T cells in vitro. These deletions did not affect infection of human skin xenografts in SCIDhu mice. These results indicate that Sp1 is required for IE62-mediated transactivation of the gE promoter and that this transcriptional factor appears to be the only cellular factor essential for regulation of the gE promoter.
View details for DOI 10.1128/JVI.00553-07
View details for Web of Science ID 000249617400007
View details for PubMedID 17634217
View details for PubMedCentralID PMC2045477
-
Genetic analysis of varicella-zoster virus ORF0 to ORF4 by use of a novel luciferase bacterial artificial chromosome system
JOURNAL OF VIROLOGY
2007; 81 (17): 9024-9033
Abstract
To efficiently generate varicella-zoster virus (VZV) mutants, we inserted a bacterial artificial chromosome (BAC) vector in the pOka genome. We showed that the recombinant VZV (VZV(BAC)) strain was produced efficiently from the BAC DNA and behaved indistinguishably from wild-type virus. Moreover, VZV's cell-associated nature makes characterizing VZV mutant growth kinetics difficult, especially when attempts are made to monitor viral replication in vivo. To overcome this problem, we then created a VZV strain carrying the luciferase gene (VZV(Luc)). This virus grew like the wild-type virus, and the resulting luciferase activity could be quantified both in vitro and in vivo. Using PCR-based mutagenesis, open reading frames (ORF) 0 to 4 were individually deleted from VZV(Luc) genomes. The deletion mutant viruses appeared after transfection into MeWo cells, except for ORF4, which was essential. Growth curve analysis using MeWo cells and SCID-hu mice indicated that ORF1, ORF2, and ORF3 were dispensable for VZV replication both in vitro and in vivo. Interestingly, the ORF0 deletion virus showed severely retarded growth both in vitro and in vivo. The growth defects of the ORF0 and ORF4 mutants could be fully rescued by introducing wild-type copies of these genes back into their native genome loci. This work has validated and justified the use of the novel luciferase VZV BAC system to efficiently generate recombinant VZV variants and ease subsequent viral growth kinetic analysis both in vitro and in vivo.
View details for DOI 10.1128/JVI.02666-06
View details for Web of Science ID 000248923700016
View details for PubMedID 17581997
View details for PubMedCentralID PMC1951468
-
Aberrant infection and persistence of varicella-zoster virus in human dorsal root ganglia in vivo absence of glycoprotein I
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2007; 104 (35): 14086-14091
Abstract
Varicella-zoster virus (VZV) causes varicella, establishes latency in sensory ganglia, and reactivates as herpes zoster. Human dorsal root ganglia (DRGs) xenografts in immunodeficient mice provide a model for evaluating VZV neuropathogenesis. Our investigation of the role of glycoprotein I (gI), which is dispensable in vitro, examines the functions of a VZV gene product during infection of human neural cells in vivo. Whereas intact recombinant Oka (rOka) initiated a short replicative phase followed by persistence in DRGs, the gI deletion mutant, rOkaDeltagI, showed prolonged replication with no transition to persistence up to 70 days after infection. Only a few varicella-zoster nucleocapsids and cytoplasmic virions were observed in neurons, and the major VZV glycoprotein, gE, was retained in the rough endoplasmic reticulum in the absence of gI. VZV neurotropism was not disrupted when DRG xenografts were infected with rOka mutants lacking gI promoter elements that bind cellular transactivators, specificity factor 1 (Sp1) and upstream stimulatory factor (USF). Because gI is essential and Sp1 and USF contribute to VZV pathogenesis in skin and T cells in vivo, these DRG experiments indicate that the genetic requirements for VZV infection are less stringent in neural cells in vivo. The observations demonstrate that gI is important for VZV neurotropism and suggest that a strategy to reduce neurovirulence by deleting gI could prolong active infection in human DRGs.
View details for DOI 10.1073/pnas.0706023104
View details for Web of Science ID 000249187500042
View details for PubMedID 17709745
View details for PubMedCentralID PMC1955823
-
The ubiquitous cellular transcriptional factor USF targets the varicella-zoster virus open reading frame 10 promoter and determines virulence in human skin xenografts in SCIDhu mice in vivo
JOURNAL OF VIROLOGY
2007; 81 (7): 3229-3239
Abstract
Varicella-zoster virus (VZV) open reading frame 10 (ORF10) is a determinant of virulence in SCIDhu skin xenografts but not in human T cells in vivo. In this analysis of the regulation of ORF10 transcription, we have identified four ORF10-related transcripts, including a major 1.3-kb RNA spanning ORF10 only and three other read-through transcripts. Rapid-amplification-of-cDNA-ends experiments indicated that the 1.3-kb transcript of ORF10 has single initiation and termination sites. In transient expression assays, the ORF10 promoter was strongly stimulated by the major VZV transactivator, IE62. Deletion analyses revealed approximate boundaries for the full ORF10 promoter activity between -75 and -45 and between +5 and -8, relative to the ORF10 transcription start site. The recombinant virus POKA10-Deltapro, with the ORF10 promoter deletion, blocked transcription of ORF10 and also of ORF9A and ORF9 mRNAs, whereas expression of read-through ORF9A/9/10 and ORF9/10 transcripts was increased, compensating for the loss of the monocistronic mRNAs. The cellular factor USF bound specifically to its consensus site within the ORF10 promoter and was required for IE62 transactivation, whereas disrupting the predicted TATA boxes or Oct-1 binding elements had no effect. The USF binding site was disrupted in the recombinant virus, POKA10-proDeltaUSF, and no ORF10 protein was produced. Both ORF10 promoter mutants reduced VZV replication in SCIDhu skin xenografts. These observations provided further evidence of the contribution of the ORF10 protein to VZV pathogenesis in skin and demonstrated that VZV depends upon the cellular transcriptional factor USF to support its virulence in human skin in vivo.
View details for DOI 10.1128/JVI.02537-06
View details for Web of Science ID 000244988100019
View details for PubMedID 17251302
View details for PubMedCentralID PMC1866059
-
Humoral and cellular immune responses in children given annual immunization with trivalent inactivated influenza vaccine
PEDIATRIC INFECTIOUS DISEASE JOURNAL
2007; 26 (2): 107-115
Abstract
There have been no prior reports of the frequency of circulating influenza-specific, interferon gamma-producing memory CD4+ and CD8+ T-cells in healthy children who have received multiple influenza immunizations.We evaluated 21 previously immunized children, ages 3 to 9 years, before and 1 month after administration of trivalent inactivated influenza vaccine. Frequencies of influenza-specific CD4+ and CD8+ T-cells stimulated with trivalent inactivated influenza vaccine or A/Panama (H3N2) virus were determined by flow cytometry, and antibody responses to vaccine strains and a drifted H3N2 strain were measured by hemagglutination inhibition assay and neutralizing antibody assays.Mean change in CD4+ and in CD8+ T-cell frequencies after immunization was 0.01% (P > 0.39) with postimmunization CD4+ frequencies higher than CD8+ frequencies. Children with more previous vaccinations had a higher baseline frequency of CD4+ T-cells (P = 0.0002) but a smaller increase or even a decline from baseline after immunization (P = 0.003). An association between age and change in frequency was not detected. Baseline geometric mean titers (GMTs) and seroprotection rates were significantly higher in older children against A/Panama (neutralizing baseline GMT, P = 0.0488) and A/New Caledonia (hemagglutination inhibition baseline GMT and seroprotection, P < 0.0297). Baseline GMTs against B/Hong Kong were not associated with age or quantity of prior vaccinations.These findings suggest that children may plateau in CD4+ T-cell responses to influenza antigens with repeated exposures and that the number of exposures may play a large role in building a memory CD4+ T-cell response to influenza A, perhaps independently from age.
View details for DOI 10.1097/01.inf.0000253251.03785.9b
View details for Web of Science ID 000243985700002
View details for PubMedID 17259871
-
Effect of maternal herpes simplex virus (HSV) serostatus and HSV type on risk of neonatal herpes
ACTA OBSTETRICIA ET GYNECOLOGICA SCANDINAVICA
2007; 86 (5): 523-529
Abstract
Neonatal herpes simplex virus (HSV) is a rare but devastating disease. We have conducted pooled analyses of data from 3 cohorts to evaluate the effects of maternal HSV serostatus and HSV type on risk of neonatal HSV acquisition and severity.Data from cohorts in Seattle, WA, and Stanford, CA, USA, and Stockholm, Sweden were pooled using Mantel-Haenszel methods.Seventy-eight infants with documented neonatal HSV and known maternal HSV serostatus were included. The risk of neonatal HSV-2 infection was similar in infants born to HSV seronegative women compared with HSV-1 seropositive women (pooled OR: 1.6; 95% CI: 0.6-4.0). The odds of neonatal HSV infection was increased in the presence of exposure to maternal HSV-1 versus HSV-2 (adjusted pooled OR: 19.2; 95% CI: 5.8-63.6). An elevated odds of disseminated HSV in infants born to women with newly acquired genital herpes was observed in Stockholm (OR=13.5; 95% CI: 1.4-630), but not in Seattle or Stanford.Our results suggest that maternal HSV-1 antibody offers little, if any, protection against neonatal HSV-2 infection. During reactivation, HSV-1 appears more readily transmissible to the neonate than HSV-2, a concerning finding given the rising frequency of genital HSV-1 infection.
View details for DOI 10.1080/00016340601151949
View details for Web of Science ID 000247237400003
View details for PubMedID 17464578
-
Comparison of the influenza virus-specific effector and memory C-cell responses to immunization of children and adults with live attenuated or inactivated influenza virus vaccines
JOURNAL OF VIROLOGY
2007; 81 (1): 215-228
Abstract
Cellular immune responses to influenza virus infection and influenza virus vaccination have not been rigorously characterized. We quantified the effector and memory B-cell responses in children and adults after administration of either live attenuated (LAIV) or inactivated (TIV) influenza virus vaccines and compared these to antibody responses. Peripheral blood mononuclear cells were collected at days 0, 7 to 12, and 27 to 42 after immunization of younger children (6 months to 4 years old), older children (5 to 9 years old), and adults. Influenza virus-specific effector immunoglobulin A (IgA) and IgG circulating antibody-secreting cells (ASC) and stimulated memory B cells were detected using an enzyme-linked immunospot assay. Circulating influenza virus-specific IgG and IgA ASC were detected 7 to 12 days after TIV and after LAIV immunization. Seventy-nine percent or more of adults and older children had demonstrable IgG ASC responses, while IgA ASC responses were detected in 29 to 53% of the subjects. The IgG ASC response rate to LAIV immunization in adults was significantly higher than the response rate measured by standard serum antibody assays (26.3% and 15.8% by neutralization and hemagglutination inhibition assays, respectively). IgG ASC and serum antibody responses were relatively low in the younger children compared to older children and adults. TIV, but not LAIV, significantly increased the percentage of circulating influenza virus-specific memory B cells detected at 27 to 42 days after immunization in children and adults. In conclusion, although both influenza vaccines are effective, we found significant differences in the B-cell and antibody responses elicited after LAIV or TIV immunization in adults and older children and between young children and older age groups.
View details for DOI 10.1128/JVI.01957-06
View details for Web of Science ID 000242958600020
View details for PubMedID 17050593
View details for PubMedCentralID PMC1797237
-
Cellular immune responses in children and adults receiving inactivated or live attenuated influenza vaccines
JOURNAL OF VIROLOGY
2006; 80 (23): 11756-11766
Abstract
The patterns of cellular immune responses induced by live attenuated influenza vaccine (LAIV) versus those of the trivalent inactivated influenza vaccine (TIV) have not been studied extensively, especially in children. The goals of this study were to evaluate the effects of TIV and LAIV immunization on cellular immunity to live influenza A virus in children and adults and to explore factors associated with variations in responses to influenza vaccines among individuals. A gamma interferon (IFN-gamma) flow cytometry assay was used to measure IFN-gamma-producing (IFN-gamma+) NK and T cells in peripheral blood mononuclear cell cultures stimulated with a live influenza A virus strain before and after LAIV or TIV immunization of children and adults. The mean percentages of influenza A virus-specific IFN-gamma+ CD4 and CD8 T cells increased significantly after LAIV, but not TIV, immunization in children aged 5 to 9 years. No increases in the mean levels of influenza A virus-reactive IFN-gamma+ T cells and NK cells were observed in adults given LAIV or TIV. TIV induced a significant increase in influenza A virus-reactive T cells in 6-month- to 4-year-old children; LAIV was not evaluated in this age group. The postvaccination changes (n-fold) in the percentages of influenza A virus-reactive IFN-gamma+ T and NK cells in adults were highly variable and correlated inversely with the prevaccination percentages, in particular with that of the CD56(dim) NK cell subset. In conclusion, our findings identify age, type of vaccine, and prevaccination levels of immune reactivity to influenza A virus as factors significantly associated with the magnitude of cellular immune responses to influenza vaccines.
View details for DOI 10.1128/JVI.01460-06
View details for Web of Science ID 000242222200032
View details for PubMedID 16971435
View details for PubMedCentralID PMC1642596
-
ORF66 protein kinase function is required for T-cell tropism of varicella-zoster virus in vivo
JOURNAL OF VIROLOGY
2006; 80 (23): 11806-11816
Abstract
Several functions have been attributed to the serine/threonine protein kinase encoded by open reading frame 66 (ORF66) of varicella-zoster virus (VZV), including modulation of the apoptosis and interferon pathways, down-regulation of major histocompatibility complex class I cell surface expression, and regulation of IE62 localization. The amino acid sequence of the ORF66 protein contains a recognizable conserved kinase domain. Point mutations were introduced into conserved protein kinase motifs to evaluate their importance to ORF66 protein functions. Two substitution mutants were generated, including a G102A substitution, which blocked autophosphorylation and altered IE62 localization, and an S250P substitution, which had no effect on either autophosphorylation or IE62 localization. Both kinase domain mutants grew to titers equivalent to recombinant parent Oka (pOka) in vitro. pOka66G102A had slightly reduced growth in skin, which was comparable to the reduction observed when ORF66 translation was prevented by stop codon insertions in pOka66S. In contrast, infection of T-cell xenografts with pOka66G102A was associated with a significant decrease in infectious virus production equivalent to the impaired T-cell tropism found with pOka66S infection of T-cell xenografts in vivo. Disrupting kinase activity with the G102A mutation did not alter IE62 cytoplasmic localization in VZV-infected T cells, suggesting that decreased T-cell tropism is due to other ORF66 protein functions. The G102A mutation reduced the antiapoptotic effects of VZV infection of T cells. These experiments indicate that the T-cell tropism of VZV depends upon intact ORF66 protein kinase function.
View details for DOI 10.1128/JVI.00466-06
View details for Web of Science ID 000242222200036
View details for PubMedID 16971426
View details for PubMedCentralID PMC1642581
-
Investigations of the pathogenesis of Varicella zoster virus infection in the SCIDhu mouse model.
Herpes : the journal of the IHMF
2006; 13 (3): 75-80
Abstract
Varicella zoster virus (VZV) is a medically important human herpesvirus that causes varicella, establishes latency in sensory ganglia and may reactivate to cause herpes zoster in healthy and immunocompromised patients. Experiments in the severe combined immunodeficiency (SCID) mouse model have provided new insights about VZV pathogenesis. In addition, the evaluation of VZV recombinant viruses, with targeted mutations of viral genes or their promoters in SCIDhu skin, T-cell and dorsal root ganglia xenografts, has the potential to identify options for the design of a recombinant 'second-generation' VZV vaccine. This would be characterized by the retention of infectivity in skin combined with a restricted tropism for T-cells and neurons within sensory ganglia.
View details for PubMedID 17147912
-
Essential functions of the unique N-terminal region of the varicella-zoster virus glycoprotein E ectodomain in viral replication and in the pathogenesis of skin infection
JOURNAL OF VIROLOGY
2006; 80 (19): 9481-9496
Abstract
Varicella-zoster virus (VZV) glycoprotein E (gE) is a multifunctional protein important for cell-cell spread, envelopment, and possibly entry. In contrast to other alphaherpesviruses, gE is essential for VZV replication. Interestingly, the N-terminal region of gE, comprised of amino acids 1 to 188, was shown not to be conserved in the other alphaherpesviruses by bioinformatics analysis. Mutational analysis was performed to investigate the functions associated with this unique gE N-terminal region. Linker insertions, serine-to-alanine mutations, and deletions were introduced in the gE N-terminal region in the VZV genome, and the effects of these mutations on virus replication and cell-cell spread, gE trafficking and localization, virion formation, and replication in vivo in the skin were analyzed. In summary, mutagenesis of the gE N-terminal region identified a new functional region in the VZV gE ectodomain essential for cell-cell spread and the pathogenesis of VZV skin tropism and demonstrated that different subdomains of the unique N-terminal region had specific roles in viral replication, cell-cell spread, and secondary envelopment.
View details for DOI 10.1128/JVI.00533-06
View details for Web of Science ID 000240647200013
View details for PubMedID 16973553
View details for PubMedCentralID PMC1617235
-
Variability and gender differences in memory T cell immunity to varicella-zoster virus in healthy adults
VACCINE
2006; 24 (33-34): 5913-5918
Abstract
Latent varicella zoster virus (VZV) can reactivate and cause zoster, the prevention of which relies upon cellular immunity to VZV. To assess temporal variation of VZV cell-mediated immunity in healthy naturally immune adults, we evaluated VZV-specific responder cell frequencies (RCF) longitudinally over 1 year in each of 25 adults. VZV-specific CD4+ T cells were detected (p < 0.003) and showed minimal variability in RCF. Additional analysis of VZV T cell RCF revealed differences between genders, with only males (p < 0.005) having detectable VZV-specific memory CD4+ T cell responses by this method. Taken together, results suggest that further studies regarding immunization of younger adults and females with the modified, high-potency live attenuated VZV vaccine may be warranted.
View details for DOI 10.1016/j.vaccine.2006.04.060
View details for Web of Science ID 000239982300001
View details for PubMedID 16759768
-
Maternal herpes simplex virus antibody avidity and risk of neonatal herpes
AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY
2006; 195 (1): 115-120
Abstract
The objective of the study was to assess whether herpes simplex virus antibody avidity is associated with risk of transmission of herpes simplex virus to the neonate.We developed a novel herpes simplex virus type 1 avidity test based on the commercially available Focus HerpeSelect-1 enzyme-linked immunosorbent assay kit using sera from nonpregnant subjects with genital herpes simplex virus-1 infection. We used this test, and the previously developed herpes simplex virus type 2 avidity test, to compare maternal herpes simplex virus-1 and herpes simplex virus-2 antibody avidity in women who transmitted herpes simplex virus to the neonate and women who had herpes simplex virus isolated from genital secretions at delivery but who did not transmit herpes simplex virus to their infants.Among nonpregnant subjects with genital herpes simplex virus-1 infection whose sera were used to develop the herpes simplex virus-1 avidity test, a significant relationship between herpes simplex virus-1 antibody avidity and time since herpes simplex virus-1 acquisition was observed (P < .001, mixed-effects model), with median avidity values increasing over time after primary infection. Among pregnant, herpes simplex virus-1, or herpes simplex virus-2 seropositive women, 4 of 8 women (50%) with avidity 40 or greater transmitted herpes simplex virus to the neonate, compared with only 12 of 97 (12%) of women with avidity greater than 40 (P = .02).Herpes simplex virus-1 antibody avidity increased over time after genital herpes simplex virus-1 acquisition, as has been previously observed for herpes simplex virus-2. Among women with herpes simplex virus antibody at delivery, low antibody avidity was associated with herpes simplex virus transmission to the neonate and may be a useful marker for recent seroconversion.
View details for DOI 10.1016/j.ajog.2006.02.013
View details for Web of Science ID 000238926700018
View details for PubMedID 16813750
-
Inhibition of the NF-kappa B pathway by varicella-zoster virus in vitro and in human epidermal cells in vivo
JOURNAL OF VIROLOGY
2006; 80 (11): 5113-5124
Abstract
Varicella-zoster virus (VZV) is an alphaherpesvirus that causes varicella and herpes zoster. Using human cellular DNA microarrays, we found that many nuclear factor kappa B (NF-kappaB)-responsive genes were down-regulated in VZV-infected fibroblasts, suggesting that VZV infection inhibited the NF-kappaB pathway. The activation of this pathway causes a cellular antiviral response, including the production of alpha/beta interferon, cytokines, and other proteins that restrict viral infection. In these experiments, we demonstrated that VZV interferes with NF-kappaB activation in cultured fibroblasts and in differentiated epidermal cells in skin xenografts of SCIDhu mice infected in vivo. VZV infection of fibroblasts caused a transient nuclear translocation of p50 and p65, the canonical NF-kappaB family members. In a process that was dependent upon the presence of infectious VZV, these proteins rapidly became sequestered in the cytoplasm of VZV-infected cells. Exclusion of NF-kappaB proteins from nuclei was associated with the continued presence of IkappaBalpha, which binds p50 and p65 and prevents their nuclear accumulation. IkappaBalpha levels did not diminish even though the protein became phosphorylated and ubiquitinated, as determined based on detection of the characteristic high-molecular-weight form of the protein, and the 26S proteasome remained functional in VZV-infected cells. VZV infection also inhibited the characteristic degradation of IkappaBalpha that is induced by exposure of fibroblasts to tumor necrosis factor alpha. As expected, herpes simplex virus 1 caused the persistent nuclear translocation of NF-kappaB proteins, which has been shown to facilitate its replication, whereas VZV infection progressed without persistent NF-kappaB nuclear localization. We suggest that VZV has evolved a mechanism to limit host cell antiviral defenses by sequestering NF-kappaB proteins in the cytoplasm, a strategy that appears to be unique among the herpesviruses.
View details for DOI 10.1128/JVI.01956-05
View details for Web of Science ID 000237753400002
View details for PubMedID 16698992
View details for PubMedCentralID PMC1472140
-
Control of varicella - Why is a two-dose schedule necessary?
PEDIATRIC INFECTIOUS DISEASE JOURNAL
2006; 25 (6): 475-476
View details for DOI 10.1097/01.inf.0000219484.55858.a2
View details for Web of Science ID 000238432300001
View details for PubMedID 16732142
-
A phase 1 study of 4 live, recombinant human cytomegalovirus Towne/Toledo chimeric vaccines
JOURNAL OF INFECTIOUS DISEASES
2006; 193 (10): 1350-1360
Abstract
Human cytomegalovirus (HCMV) infection acquired in utero often results in severe consequences, including mental retardation and deafness. Although not evaluated for this indication, live attenuated HCMV vaccines based on the Towne strain are well-tolerated and have demonstrated moderate efficacy in other clinical settings.To produce live HCMV vaccine candidates that retain the excellent safety profile of the Towne strain but are more immunogenic, the genomes of the Towne strain and the unattenuated HCMV Toledo strain were recombined to yield 4 independent chimeric vaccine candidates. These vaccine candidates were evaluated in 20 HCMV-seropositive persons, in a phase 1, double-blinded, placebo-controlled trial. Participants received a single dose of vaccine or placebo, and the safety and tolerability of the vaccine candidates were evaluated.There was no difference in systemic symptoms between the vaccine and placebo recipients. As a group, vaccine recipients experienced more injection-site reactions than did placebo recipients; however, these were generally minor and short-lived. Vaccine virus could not be detected in blood, urine, or saliva samples obtained from any vaccine recipient.The Towne/Toledo chimeric vaccine candidates were well tolerated and did not cause systemic infection. Additional human trials are warranted to further evaluate the potential of these vaccine candidates as live virus vaccines.
View details for Web of Science ID 000237053400003
View details for PubMedID 16619181
-
Varicella-zoster virus open reading frame 10 is a virulence determinant in skin cells but not in T cells in vivo
JOURNAL OF VIROLOGY
2006; 80 (7): 3238-3248
Abstract
The open reading frame 10 (ORF10) of varicella-zoster virus (VZV) encodes a tegument protein that enhances transactivation of VZV genes and has homology to herpes simplex virus type 1 (HSV-1) VP16. While VP16 is essential for HSV replication, ORF10 is dispensable for vaccine OKA (VOKA) growth in vitro. We used parent OKA (POKA) cosmids to delete ORF10, producing POKA delta10; point mutations that disrupted the acidic activation domain and the putative motif for binding human cellular factor 1 (HCF-1) in ORF10 protein yielded POKA10-Phe28Ala, POKA10-Phe28Ser, and POKA10-mHCF viruses. Deleting ORF10 or mutating these two functional domains had no effect on VZV replication, immediate-early gene transcription, or virion assembly in vitro. However, deleting ORF10 reduced viral titers and the extent of cutaneous lesions significantly in SCIDhu skin xenografts in vivo compared to POKA. Epidermal cells infected with POKA delta10 had significantly fewer DNA-containing nucleocapsids and complete virions compared to POKA; extensive aggregates of intracytoplasmic viral particles were also observed. Altering the activation or the putative HCF-1 domains of ORF10 protein had no consequences for VZV replication in vivo. Thus, the decreased pathogenic potential of POKA delta10 in skin could not be attributed to absence of these ORF10 protein functions. In contrast to skin cells, deleting ORF10 did not impair VZV T-cell tropism in vivo, as assessed by infectious virus yields. We conclude that ORF10 protein is required for efficient VZV virion assembly and is a specific determinant of VZV virulence in epidermal and dermal cells in vivo.
View details for DOI 10.1128/JVI.80.7.3238-3248.2006
View details for Web of Science ID 000236305200011
View details for PubMedID 16537591
View details for PubMedCentralID PMC1440391
-
Mutational analysis of the Varicella-Zoster virus ORF62/63 Intergenic region
JOURNAL OF VIROLOGY
2006; 80 (6): 3116-3121
Abstract
The varicella-zoster virus (VZV) ORF62/63 intergenic region was cloned between the Renilla and firefly luciferase genes, which acted as reporters of ORF62 and ORF63 transcription, and recombinant viruses were generated that carried these reporter cassettes along with the intact native sequences in the repeat regions of the VZV genome. In order to investigate the potential contributions of cellular transregulatory proteins to ORF62 and ORF63 transcription, recombinant reporter viruses with mutations of consensus binding sites for six proteins within the intergenic region were also created. The reporter viruses were used to evaluate ORF62 and ORF63 transcription during VZV replication in cultured fibroblasts and in skin xenografts in SCIDhu mice in vivo. Mutations in putative binding sites for heat shock factor 1 (HSF-1), nuclear factor 1 (NF-1), and one of two cyclic AMP-responsive elements (CRE) reduced ORF62 reporter transcription in fibroblasts, while mutations in binding sites for HSF-1, NF-1, and octamer binding proteins (Oct-1) increased ORF62 reporter transcription in skin. Mutations in one CRE and the NF-1 site altered ORF63 transcription in fibroblasts, while mutation of the Oct-1 binding site increased ORF63 reporter transcription in skin. The effect of each of these mutations implies that the intact binding site sequence regulates native ORF62 and ORF63 transcription. Mutation of the only NF-kappaB/Rel binding site had no effect on ORF62 or ORF63 transcription in vitro or in vivo. The segment of the ORF62/63 intergenic region proximal to ORF63 was most important for ORF63 transcription, but mutagenesis also altered ORF62 transcription, indicating that this region functions as a bidirectional promoter. This first analysis of the ORF62/63 intergenic region in the context of VZV replication indicates that it is a dual promoter and that cellular transregulatory factors affect the transcription of these key VZV regulatory genes.
View details for DOI 10.1128/JVI.80.6.3116-3121.2006
View details for Web of Science ID 000236131400057
View details for PubMedID 16501125
View details for PubMedCentralID PMC1395429
-
Immunogenicity of aerosol measles vaccine given as the primary measles immunization to nine-month-old Mexican children
42nd Annual Meeting of the Infectious-Diseases-Society-of-America
ELSEVIER SCI LTD. 2006: 683–90
Abstract
Aerosol measles vaccination has been found to be more immunogenic than subcutaneous administration as a booster in school aged children, and immunogenic in 12-month-old children as a primary dose. The objective of the study was to evaluate immunogenicity to aerosol measles vaccine in 9-month-old children.Nine-months-old infants received Edmonston-Zagreb measles vaccine by aerosol (10(3.58) CCID50/0.1 mL, estimated retained dose 10(2.81) CCID50 or subcutaneous route (10(4.28) CCID50/0.5 mL); cellular and humoral immunity and adverse events were assessed.Measles-specific T cell proliferative responses developed in 42% of children given aerosolized vaccine compared with 67% of those who received subcutaneous vaccine (p = 0.01); the mean stimulation index (SI) was 4.4+/-0.7 versus 6.9+/-1, respectively, (p = 0.05). Seroconversion rates were 33 and 92% after aerosol or subcutaneous immunization (p < 0.001). Among infants who developed serologic responses, measles geometric mean titers (GMT; 95% CI) by neutralizing antibody assay were 215 mIU/mL (115-400) in aerosol vaccine recipients and 411 mIU/mL (345-490) in those given subcutaneous vaccine (p = 0.06).The proportion of 9-month-old infants who developed cellular and/or humoral immunity to measles was lower in the aerosol group but measles antibody and T cell responses were comparable among those who developed measles immunity. Differences in response rates are attributable to the lower aerosol dose. Improving aerosol delivery or increasing the dose may enhance immunogenicity of primary aerosol measles vaccination in this age group.
View details for DOI 10.1016/j.vaccine.2005.08.045
View details for Web of Science ID 000235273900017
View details for PubMedID 16154241
-
New viral vaccines
VIROLOGY
2006; 344 (1): 240-249
Abstract
Vaccination is the most effective medical intervention against diseases caused by human viral pathogens. Viral vaccines prevent or modify the severity of illness in the individual and interrupt or reduce the transmission of the pathogens to other susceptible people. Through these mechanisms, vaccines against smallpox, polio, measles and hepatitis B have had an enormous impact on world health over the last 50 years. Advances in basic virology and understanding of human immunity promise more progress in the control of human viral diseases as the 21st century begins. Some important targets, including human immunodeficiency virus, respiratory syncytial virus and hepatitis C virus present challenges that require more basic research. The purpose of this review is to highlight four new viral vaccines that have recently, or will soon demonstrate the effective translation of basic investigations into clinical benefits for disease control in healthy and high-risk populations. These vaccines include the live attenuated vaccines against the RNA viruses, rotavirus and influenza A and B, and vaccines against human papilloma virus and varicella-zoster virus, which are DNA viruses that cause morbidity and mortality through their capacity to establish persistent infection. Although only the influenza vaccine has been licensed in the United States, these other new tools for disease prevention are likely to be introduced within the next few years, with profound effects on the diseases that they cause. Hence, as Virology celebrates its 50th anniversary, it is appropriate to examine these examples of recent advances in viral vaccines.
View details for DOI 10.1016/j.virol.2005.09.057
View details for Web of Science ID 000234611000026
View details for PubMedID 16364754
-
Varicella-zoster virus ORF63 inhibits apoptosis of primary human neurons
JOURNAL OF VIROLOGY
2006; 80 (2): 1025-1031
Abstract
Virus-encoded modulation of apoptosis may serve as a mechanism to enhance cell survival and virus persistence. The impact of productive varicella-zoster virus (VZV) infection on apoptosis appears to be cell type specific, as infected human sensory neurons are resistant to apoptosis, yet human fibroblasts readily become apoptotic. We sought to identify the viral gene product(s) responsible for this antiapoptotic phenotype in primary human sensory neurons. Treatment with phosphonoacetic acid to inhibit viral DNA replication and late-phase gene expression did not alter the antiapoptotic phenotype, implicating immediate-early (IE) or early genes or a virion component. Compared to the parental VZV strain (rOKA), a recombinant virus unable to express one copy of the diploid IE gene ORF63 (rOka deltaORF63) demonstrated a significant induction of apoptosis in infected neurons, as determined by three methods: annexin V staining, deoxynucleotidyltransferase-mediated dUTP-biotin nick end label staining, and transmission electron microscopy. Furthermore, neurons transfected with a plasmid expressing ORF63 resisted apoptosis induced by nerve growth factor withdrawal. These results show that ORF63 can suppress apoptosis of neurons and provide the first identification of a VZV gene encoding an antiapoptotic function. As ORF63 is expressed in neurons during both productive and latent infection, it may play a significant role in viral pathogenesis by promoting neuron survival during primary and reactivated infections.
View details for DOI 10.1128/JVI.80.2.1025-1031.2006
View details for Web of Science ID 000234382900047
View details for PubMedID 16379003
View details for PubMedCentralID PMC1346839
-
Reducing the global burden of congenital rubella syndrome: Report of the World Health Organization Steering Committee on Research Related to Measles and Rubella Vaccines and Vaccination, June 2004
JOURNAL OF INFECTIOUS DISEASES
2005; 192 (11): 1890-1897
Abstract
Rubella and congenital rubella syndrome (CRS) continue to be important health problems in many countries. In June 2004, the World Health Organization Steering Committee on Research Related to Measles and Rubella Vaccines and Vaccination met to evaluate data from research and operational activities and to identify critical scientific issues and gaps in knowledge that need to be addressed to improve the global control of rubella and CRS. Information about surveillance for rubella, natural and vaccine-induced immunity to rubella, laboratory diagnosis, the molecular epidemiological profile of rubella virus, and mathematical modeling to assess the burden of CRS and the impact of rubella vaccination was reviewed. This report summarizes the presentations and recommendations for future research.
View details for Web of Science ID 000233018200006
View details for PubMedID 16267759
-
Viral and cellular gene transcription in fibroblasts infected with small plaque mutants of varicella-zoster virus
ANTIVIRAL RESEARCH
2005; 68 (2): 56-65
Abstract
Varicella-zoster virus (VZV) is an alphaherpesvirus that causes varicella and herpes zoster. In these experiments, cDNA corresponding to 69 VZV open reading frames was added to 42K human cDNA microarrays and used to examine viral as well as cellular gene transcription concurrently in fibroblasts infected with two genetically distinct small plaque VZV mutants, rOka/ORF63rev[T171] and rOkaDeltagI. rOka/ORF63rev[T171] has a point mutation in ORF63, which encodes the immediate early regulatory protein, IE63, and rOkaDeltagI has a deletion of ORF67, encoding glycoprotein I (gI). rOka/ORF63rev[T171] was deficient in the transcription of several viral genes compared to the recombinant rOka control virus. Deletion of ORF67 had minimal effects on viral gene transcription. Effects of rOka/ORF63rev[T171] and rOkaDeltagI on host cell gene transcription were similar to the rOka control, but a few host cell genes were regulated differently in rOkaDeltagI-infected cells. Infection of fibroblasts with intact or small plaque VZV mutants was associated with down-regulation of NF-kappaB and interferon responsive genes, down-regulation of TGF-beta responsive genes accompanied by reduced amounts of fibrotic/wound healing response genes (e.g. collagens, follistatin) and activation of cellular proliferation genes, and alteration of neuronal growth markers, as well as cellular genes encoding proteins important in protein and vesicle trafficking. These observations suggest that replication of VZV small plaque mutant viruses and intact VZV have similar consequences for host cell gene transcription in infected cells, and that the small plaque phenotype in these mutants reflects deficiencies in viral gene expression.
View details for DOI 10.1016/j.antiviral.2005.06.011
View details for Web of Science ID 000233509700002
View details for PubMedID 16118026
-
T-Cell tropism and the role of ORF66 protein in pathogenesis of varicella-zoster virus infection
JOURNAL OF VIROLOGY
2005; 79 (20): 12921-12933
Abstract
The pathogenesis of varicella-zoster virus (VZV) involves a cell-associated viremia during which infectious virus is carried from sites of respiratory mucosal inoculation to the skin. We now demonstrate that VZV infection of T cells is associated with robust virion production and modulation of the apoptosis and interferon pathways within these cells. The VZV serine/threonine protein kinase encoded by ORF66 is essential for the efficient replication of VZV in T cells. Preventing ORF66 protein expression by stop codon insertion (pOka66S) impaired the growth of the parent Oka (pOka) strain in T cells in SCID-hu T-cell xenografts in vivo and reduced formation of VZV virions. The lack of ORF66 protein also increased the susceptibility of infected T cells to apoptosis and reduced the capacity of the virus to interfere with induction of the interferon (IFN) signaling pathway following exposure to IFN-gamma. However, preventing ORF66 protein expression only slightly reduced growth in melanoma cells in culture and did not diminish virion formation in these cells. The pOka66S virus showed only a slight defect in growth in SCID-hu skin implants compared with intact pOka. These observations suggest that the ORF66 kinase plays a unique role during infection of T cells and supports VZV T-cell tropism by contributing to immune evasion and enhancing survival of infected T cells.
View details for DOI 10.1128/JVI.79.20.12921-12933.2005
View details for Web of Science ID 000232243200032
View details for PubMedID 16188994
View details for PubMedCentralID PMC1235817
-
Strengthening the nation's influenza vaccination system - A national vaccine advisory committee assessment
AMERICAN JOURNAL OF PREVENTIVE MEDICINE
2005; 29 (3): 221-226
View details for DOI 10.1016/j.amepre.2005.05.011
View details for Web of Science ID 000232187900010
View details for PubMedID 16168873
-
Cell-type-dependent activation of the cellular EF-1 alpha promoter by the varicella-zoster virus IE63 protein
VIROLOGY
2005; 338 (1): 35-42
Abstract
The varicella-zoster virus (VZV) IE63 protein is abundantly expressed during productive viral infection and is one of six gene products that appear to be expressed during latency. We have found that the IE63 protein can activate expression from the cellular EF-1alpha promoter in the absence of other viral proteins. The VZV IE62 protein, in contrast, was not found to transactivate this promoter. These data indicate that IE63 can function independently of the IE62 protein to positively influence the cellular transcription apparatus. We show that IE63 activation of the EF-1alpha promoter is cell type dependent and have examined the effects of point mutations important for IE63 phosphorylation and virus viability on this activation.
View details for DOI 10.1016/j.virol.2005.05.005
View details for Web of Science ID 000230470400004
View details for PubMedID 15936796
-
Aging, immunity, and the varicella-zoster virus
NEW ENGLAND JOURNAL OF MEDICINE
2005; 352 (22): 2266-2267
View details for Web of Science ID 000229446400002
View details for PubMedID 15930416
-
Varicella-zoster virus infection of human dorsal root ganglia in vivo
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2005; 102 (18): 6490-6495
Abstract
Varicella-zoster virus (VZV) causes varicella and establishes latency in sensory ganglia. VZV reactivation results in herpes zoster. We developed a model using human dorsal root ganglion (DRG) xenografts in severe combined immunodeficient (SCID) mice to investigate VZV infection of differentiated neurons and satellite cells in vivo. DRG engrafted under the kidney capsule and contained neurons and satellite cells within a typical DRG architecture. VZV clinical isolates infected the neurons within DRG. At 14 days postinfection, VZ virions were detected by electron microscopy in neuronal cell nuclei and cytoplasm but not in satellite cells. The VZV genome copy number was 7.1 x 10(7) to 8.0 x 10(8) copies per 10(5) cells, and infectious virus was recovered. This initial phase of viral replication was followed within 4-8 weeks by a transition to VZV latency, characterized by the absence of infectious virus release, the cessation of virion assembly, and a reduction in VZV genome copies to 3.7 x 10(5) to 4.7 x 10(6) per 10(5) cells. VZV persistence in DRG was achieved without any requirement for VZV-specific adaptive immunity and was associated with continued transcription of the ORF63 regulatory gene. The live attenuated varicella vaccine virus exhibited the same pattern of short-term replication, persistence of viral DNA, and prominent ORF63 transcription as the clinical isolates. VZV-infected T cells transferred virus from the circulation into DRG, suggesting that VZV lymphotropism facilitates its neurotropism. DRG xenografts may be useful for investigating neuropathogenic mechanisms of other human viruses.
View details for DOI 10.1073/pnas.0501045102
View details for Web of Science ID 000228918400045
View details for PubMedID 15851670
View details for PubMedCentralID PMC1088374
-
Role of the varicella-zoster virus gene product encoded by open reading frame 35 in viral replication in vitro and in differentiated human skin and T cells in vivo
JOURNAL OF VIROLOGY
2005; 79 (8): 4819-4827
Abstract
Although genes related to varicella-zoster virus (VZV) open reading frame 35 (ORF35) are conserved in the herpesviruses, information about their contributions to viral replication and pathogenesis is limited. Using a VZV cosmid system, we deleted ORF35 to produce two null mutants, designated rOkaDelta35(#1) and rOkaDelta35(#2), and replaced ORF35 at a nonnative site, generating two rOkaDelta35/35@Avr mutants. ORF35 Flag-tagged recombinants were made by inserting ORF35-Flag at the nonnative Avr site as the only copy of ORF35, yielding rOkaDelta35/35Flag@Avr, or as a second copy, yielding rOka35Flag@Avr. Replication of rOkaDelta35 viruses was diminished in melanoma and Vero cells in a 6-day analysis of growth kinetics. Plaque sizes of rOkaDelta35 mutants were significantly smaller than those of rOka in melanoma cells. Infection of melanoma cells with rOkaDelta35 mutants was associated with disrupted cell fusion and polykaryocyte formation. The small plaque phenotype was not corrected by growth of rOkaDelta35 mutants in melanoma cells expressing the major VZV glycoprotein E, gE. The rOkaDelta35/35@Avr viruses displayed growth kinetics and plaque morphologies that were indistinguishable from those of rOka. Analysis with ORF35-Flag recombinants showed that the ORF35 gene product localized predominantly to the nuclei of infected cells. Evaluations in the SCIDhu mouse model demonstrated that ORF35 was required for efficient VZV infection of skin and T-cell xenografts, although the decrease in infectivity was most significant in skin. These mutagenesis experiments indicated that ORF35 was dispensable for VZV replication, but deleting ORF35 diminished growth in cultured cells and was associated with attenuated VZV infection of differentiated human skin and T cells in vivo.
View details for DOI 10.1128/JVI.79.8.4819-4827.2005
View details for Web of Science ID 000228073700026
View details for PubMedID 15795267
View details for PubMedCentralID PMC1069565
-
Varicella-Zoster virus pathogenesis and immunobiology: New concepts emerging from investigations with the SCIDhu mouse model
JOURNAL OF VIROLOGY
2005; 79 (5): 2651-2658
View details for DOI 10.1128/JVI.79.5.2651-2658.2005
View details for Web of Science ID 000227098400001
View details for PubMedID 15708984
View details for PubMedCentralID PMC548427
-
Analysis of varicella zoster virus attenuation by evaluation of chimeric parent Oka/vaccine Oka recombinant viruses in skin xenografts in the SCIDhu mouse model
VIROLOGY
2005; 332 (1): 337-346
Abstract
Varicella-zoster virus (VZV) is the only human herpes virus for which a vaccine has been licensed. A clinical VZV isolate, designated the parent Oka (pOka) strain was passed in human and non-human fibroblasts to produce vaccine Oka (vOka). The pOka and vOka viruses exhibit similar infectivity in cultured cells but healthy susceptible individuals given vaccines derived from vOka rarely develop the cutaneous vesicular lesions characteristic of varicella. Inoculation of skin xenografts in the SCIDhu mouse model of VZV pathogenesis demonstrated that vOka had a reduced capacity to replicate in differentiated human epidermal cells in vivo (Moffat, J.F., Zerboni, L., Kinchington, P.R., Grose, C., Kaneshima, H., Arvin A.M., 1998a. Attenuation of the vaccine Oka strain of varicella-zoster virus and role of glycoprotein C in alphaherpesvirus virulence demonstrated in the SCID-hu mouse. J Virol. 72:965-74). In order to investigate the attenuation of vOka in skin, we made chimeric pOka and vOka recombinant viruses from VZV cosmids. Six chimeric pOka/vOka viruses were generated using cosmid sets that incorporate linear overlapping fragments of VZV DNA from cells infected with pOka or vOka. The cosmid sets consist of pOka and vOka DNA segments that have identical restriction sites. As expected, the growth kinetics and plaque morphologies of the six chimeric pOka/vOka viruses were indistinguishable in vitro. However, the chimeric viruses exhibited varying capacities to replicate when evaluated in skin xenografts in vivo. The presence of ORFs 30-55 from the pOka genome was sufficient to maintain wild-type infectivity in skin. Chimeric viruses containing different vOka components retained the attenuation phenotype, suggesting that vOka attenuation is multi-factorial and can be produced by genes from different regions of the vOka genome.
View details for DOI 10.1016/j.virol.2004.10.047
View details for Web of Science ID 000226688500032
View details for PubMedID 15661165
-
Chickenpox party or varicella vaccine?
Course on Infection and Immunity in Children 2004
SPRINGER. 2005: 11–24
Abstract
The most compelling rationale for introducing universal vaccination against varicella was the predicted benefits to healthy children. Current evidence from the US experience indicates that these benefits are being realized. As is true for any new vaccine, implementation of such a program necessitates disease surveillance and modifications of the vaccine regimen as needed. In the case of VZV, the epidemiology of herpes zoster must be tracked as well as varicella disease trends. The prevention of herpes zoster may be another use of live attenuated or inactivated varicella vaccines.
View details for Web of Science ID 000233299500002
View details for PubMedID 16107063
-
T cell-dependent production of IFN-gamma by NK cells in response to influenza A virus
JOURNAL OF CLINICAL INVESTIGATION
2004; 114 (12): 1812-1819
Abstract
The role of human NK cells in viral infections is poorly understood. We used a cytokine flow-cytometry assay to simultaneously investigate the IFN-gamma response of NK and T lymphocytes to influenza A virus (fluA). When PBMCs from fluA-immune adult donors were incubated with fluA, IFN-gamma was produced by both CD56(dim) and CD56(bright) subsets of NK cells, as well as by fluA-specific T cells. Purified NK cells did not produce IFN-gamma in response to fluA, while depletion of T lymphocytes reduced to background levels the fluA-induced IFN-gamma production by NK cells, which indicates that T cells are required for the IFN-gamma response of NK cells. The fluA-induced IFN-gamma production of NK cells was suppressed by anti-IL-2 Ab, while recombinant IL-2 replaced the helper function of T cells for IFN-gamma production by NK cells. This indicates that IL-2 produced by fluA-specific T cells is involved in the T cell-dependent IFN-gamma response of NK cells to fluA. Taken together, these results suggest that at an early stage of recurrent viral infection, NK-mediated innate immunity to the virus is enhanced by preexisting virus-specific T cells.
View details for DOI 10.1172/JCI200422797
View details for Web of Science ID 000225695800016
View details for PubMedID 15599406
View details for PubMedCentralID PMC535070
-
Differential requirement for cell fusion and virion formation in the pathogenesis of varicella-zoster virus infection in skin and T cells
JOURNAL OF VIROLOGY
2004; 78 (23): 13293-13305
Abstract
The protein product of varicella-zoster virus (VZV) ORF47 is a serine/threonine protein kinase and tegument component. Evaluation of two recombinants of the Oka strain, rOka47DeltaC, with a C-terminal truncation of ORF47, and rOka47D-N, with a point mutation in the conserved kinase motif, showed that ORF47 kinase function was necessary for optimal VZV replication in human skin xenografts in SCID mice but not in cultured cells. We now demonstrate that rOka47DeltaC and rOka47D-N mutants do not infect human T-cell xenografts. Differences in the growth of kinase-defective ORF47 mutants allowed an examination of requirements for VZV pathogenesis in skin and T cells in vivo. Although virion assembly was reduced and no virion transport to cell surfaces was observed, epidermal cell fusion persisted, and VZV polykaryocytes were generated by rOka47DeltaC and rOka47D-N in skin. Virion assembly was also impaired in vitro, but VZV-induced cell fusion continued to cause syncytia in cultured cells infected with rOka47DeltaC or rOka47D-N. Intracellular trafficking of envelope glycoprotein E and the ORF47 and IE62 proteins, components of the tegument, was aberrant without ORF47 kinase activity. In summary, normal VZV virion assembly appears to require ORF47 kinase function. Cell fusion was induced by ORF47 mutants in skin, and cell-cell spread occurred even though virion formation was deficient. VZV-infected T cells do not undergo cell fusion, and impaired virion assembly by ORF47 mutants was associated with a complete elimination of T-cell infectivity. These observations suggest a differential requirement for cell fusion and virion formation in the pathogenesis of VZV infection in skin and T cells.
View details for DOI 10.1128/JVI.78.23.13293-13305.2004
View details for Web of Science ID 000225087500056
View details for PubMedID 15542680
View details for PubMedCentralID PMC524993
-
Functions of the C-terminal domain of varicella-zoster virus glycoprotein E in viral replication in vitro and skin and T-cell tropism in vivo
JOURNAL OF VIROLOGY
2004; 78 (22): 12406-12415
Abstract
Varicella-zoster virus (VZV) glycoprotein E (gE) is essential for VZV replication. To further analyze the functions of gE in VZV replication, a full deletion and point mutations were made in the 62-amino-acid (aa) C-terminal domain. Targeted mutations were introduced in YAGL (aa 582 to 585), which mediates gE endocytosis, AYRV (aa 568 to 571), which targets gE to the trans-Golgi network (TGN), and SSTT, an "acid cluster" comprising a phosphorylation motif (aa 588 to 601). Substitutions Y582G in YAGL, Y569A in AYRV, and S593A, S595A, T596A, and T598A in SSTT were introduced into the viral genome by using VZV cosmids. These experiments demonstrated a hierarchy in the contributions of these C-terminal motifs to VZV replication and virulence. Deletion of the gE C terminus and mutation of YAGL were lethal for VZV replication in vitro. Mutations of AYRV and SSTT were compatible with recovery of VZV, but the AYRV mutation resulted in rapid virus spread in vitro and the SSTT mutation resulted in higher virus titers than were observed for the parental rOka strain. When the rOka-gE-AYRV and rOka-gE-SSTT mutants were evaluated in skin and T-cell xenografts in SCIDhu mice, interference with TGN targeting was associated with substantial attenuation, especially in skin, whereas the SSTT mutation did not alter VZV infectivity in vivo. These results provide the first information about how targeted mutations of this essential VZV glycoprotein affect viral replication in vitro and VZV virulence in dermal and epidermal cells and T cells within intact tissue microenvironments in vivo.
View details for DOI 10.1128/JVI.78.22.12406-12415.2004
View details for Web of Science ID 000224781400032
View details for PubMedID 15507627
View details for PubMedCentralID PMC525039
-
Varicella-zoster virus transfer to skin by T cells and modulation of viral replication by epidermal cell interferon-alpha
JOURNAL OF EXPERIMENTAL MEDICINE
2004; 200 (7): 917-925
Abstract
Primary infection with varicella-zoster virus (VZV) causes the characteristic syndrome of varicella, or chickenpox. Experiments in severe combined immunodeficiency mice with human skin grafts (SCIDhu mice) indicate that VZV infection of T cells can mediate transfer of infectious virus to skin. VZV-infected T cells reached epithelial sites of replication within 24 h after entering the circulation. Memory CD4+ T cells were the predominant population recovered from skin in SCIDhu mice given uninfected or infected mononuclear cells, suggesting that immune surveillance by memory T cells may facilitate VZV transfer. The increased susceptibility of memory T cells to VZV infection may further enhance their role in VZV pathogenesis. During VZV skin infection, viral gene products down-regulated interferon-alpha to permit focal replication, whereas adjacent epidermal cells mounted a potent interferon-alpha response against cell-cell spread. Interleukin-1alpha, although activated in VZV-infected cells, did not trigger expression of endothelial adhesion molecules, thereby avoiding early recruitment of inflammatory cells. The prolonged varicella incubation period appears to represent the time required for VZV to overcome antiviral responses of epidermal cells and generate vesicles at the skin surface. Modulation of VZV replication by cutaneous innate immunity may avoid an incapacitating infection of the host that would limit opportunities for VZV transmission.
View details for DOI 10.1084/jem.20040634
View details for Web of Science ID 000224380700009
View details for PubMedID 15452178
View details for PubMedCentralID PMC2213285
-
Varicella-zoster virus infection of human neural cells in vivo
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2004; 101 (29): 10792-10797
Abstract
Varicella-zoster virus (VZV) establishes latency in sensory ganglia and causes herpes zoster upon reactivation. These investigations in a nonobese diabetic severe combined immunodeficient mouse-human neural cell model showed that VZV infected both neurons and glial cells and spread efficiently from cell to cell in vivo. Neural cell morphology and protein synthesis were preserved, in contrast to destruction of epithelial cells by VZV. Expression of VZV genes in neural cells was characterized by nuclear retention of the major viral transactivating protein and a block in synthesis of the predominant envelope glycoprotein. The attenuated VZV vaccine strain retained infectivity for neurons and glial cells in vivo. VZV gene expression in differentiated human neural cells in vivo differs from neural infection by herpes simplex virus, which is characterized by latency-associated transcripts, and from lytic VZV replication in skin. The chimeric nonobese diabetic severe combined immunodeficient mouse model may be useful for investigating other neurotropic human viruses.
View details for DOI 10.1073/pnas.0404016101
View details for Web of Science ID 000222842700055
View details for PubMedID 15247414
View details for PubMedCentralID PMC490013
-
Vaccine development to prevent cytomegalovirus disease: Report from the National Vaccine Advisory Committee
CLINICAL INFECTIOUS DISEASES
2004; 39 (2): 233-239
Abstract
Cytomegalovirus (CMV) infection is the most common intrauterine infection in the United States, and it exacts a heavy toll when it infects children and immunocompromised individuals. A CMV vaccine was assigned the highest priority by the Institute of Medicine in its 1999 assessment of targets for vaccine development. The priority was based on the cost and human suffering that would be alleviated by reducing the disease burden of congenital CMV infection. The National Vaccine Advisory Committee and invited experts examined the prospects for a CMV vaccine and the actions needed to bring about successful vaccine development at a National Vaccine Program Office workshop in October 2000. This article summarizes information about the changing epidemiology of CMV and immune responses to infection and immunity, and it reviews the current status of several vaccine candidates. Support of government agencies for CMV vaccine research and development is critical to address this need.
View details for Web of Science ID 000222474300014
View details for PubMedID 15307033
-
Humoral and cell-mediated immune responses to an early 2-dose measles vaccination regimen in the United States
41st Annual Meeting of the Infectious-Diseases-Society-of-America
UNIV CHICAGO PRESS. 2004: 83–90
Abstract
Shifts in peak measles incidence to children <12 months old and the associated high mortality support the study of an early 2-dose measles vaccine regimen.Fifty-five infants were vaccinated with measles vaccine at age 6 (n=32) or 9 (n=23) months, followed by measles-mumps-rubella (MMR)-II vaccine at age 12 months. A control group received MMR-II only at age 12 months. Measles-specific humoral and cell-mediated immunity were evaluated before, 12 weeks after measles immunization, and 24 weeks after MMR-II.Measles-specific T cell proliferation after both doses of vaccine was equivalent, regardless of age or the presence of passive antibodies. Seroconversion rates, geometric mean titers, and the percentage of infants with antibody titers >120 mIU after the first measles vaccine were lower in infants vaccinated at age 6 months, regardless of the presence of passive antibodies, but measles humoral responses increased after the administration of MMR-II vaccine in children initially vaccinated at age 6 or 9 months.Measles vaccination elicits T cell responses in infants as young as 6 months old, which may prime the humoral response to the second dose. Initiating measles vaccination as an early 2-dose regimen results in an immunologic response that is likely to have clinical benefits in developed and developing countries.
View details for PubMedID 15195246
-
T cell immunity to measles viral proteins in infants and adults after measles immunization
VIRAL IMMUNOLOGY
2004; 17 (2): 298-307
Abstract
Vaccination of infants against measles remains of global importance, and proposed new vaccine strategies include the use of measles proteins or synthetic peptides as immunogens. We studied cell-mediated immunity to whole measles antigen and measles proteins in immune adults and infants after measles vaccine. Further, we measured CD8+ T cell responses to peptide pools corresponding to the nucelocapsid (N) measles protein in adults given measles vaccine. Cell-mediated immune responses to three of four measles proteins were equivalent to those against whole measles antigen in immune adults. Responses to the fusion (F) protein were lower in infants compared to whole measles antigen (p < or = 0.03). Infant responses to both whole measles antigen and the F protein were lower compared with these responses in adults (p < or = 0.001). CD8+ T cell responses to N peptide pools varied, and differed between immune HLA-A2-positive individuals compared with naive and HLA-A2-negative subjects after measles vaccination. The measles-specific T cell adaptive response of infants is limited compared to adults, including responses to the F protein.
View details for PubMedID 15279707
-
Antiviral CD8 T cells in the control of primary human cytomegalovirus infection in early childhood
40th Annual Meeting of the Infectious-Diseases-Society-of-America
UNIV CHICAGO PRESS. 2004: 1619–27
Abstract
Human cytomegalovirus (CMV) establishes persistent infection, with control of replication thought to be mediated by CMV-specific CD8 T cells. Primary CMV infection commonly affects young children and causes prolonged viral shedding in saliva and urine. We investigated whether this virus-host interaction pattern reflects a developmental deficiency of antiviral CD8 T cell-mediated immunity during childhood. CMV-specific CD8 T cell responses in asymptomatic children with active infection were not different from adults with recent or long-term infection in frequency and functional analyses. High urine CMV concentrations were detected, despite these CMV-specific CD8 T cell responses. We conclude that delayed resolution of primary CMV infection in young children is not caused by a deficient CMV-specific CD8 T cell response. Because these healthy children continue to have local CMV replication, we suggest that CD8 T cells may function primarily to prevent symptomatic, disseminated disease.
View details for PubMedID 15116298
-
Persistent and selective deficiency of CD4(+) T cell immunity to cytomegalovirus in immunocompetent young children
JOURNAL OF IMMUNOLOGY
2004; 172 (5): 3260-3267
Abstract
Healthy young children who acquire CMV have prolonged viral shedding into the urine and saliva, but whether this is attributable to limitations in viral-specific immune responses has not been explored. In this study, we found that otherwise immunocompetent young children after recent primary CMV infection accumulated markedly fewer CMV-specific CD4(+) T cells that produced IFN-gamma than did adults. These differences in CD4(+) T cell function persisted for more than 1 year after viral acquisition, and did not apply to CMV-specific IFN-gamma production by CD8(+) T cells. The IFN-gamma-producing CD4(+) T cells of children or adults that were reactive with CMV Ags were mainly the CCR7(low) cell subset of memory (CD45R0(high)CD45RA(low)) cells. The decreased IFN-gamma response to CMV in children was selective, because their CCR7(low) memory CD4(+) T cells and those of adults produced similar levels of this cytokine after stimulation with staphylococcal enterotoxin B superantigen. CD4(+) T cells from children also had reduced CMV-specific IL-2 and CD154 (CD40 ligand) expression, suggesting an early blockade in the differentiation of viral-specific CD4(+) T cells. Following CMV acquisition, children, but not adults, persistently shed virus in urine, and this was observable for at least 29 mo postinfection. Thus, CD4(+) T cell-mediated immunity to CMV in humans is generated in an age-dependent manner, and may have a substantial role in controlling renal viral replication and urinary shedding.
View details for PubMedID 14978134
-
The immediate-early 63 protein of varicella-zoster virus: Analysis of functional domains required for replication in vitro and for T-cell and skin tropism in the SCIDhu model in vivo
JOURNAL OF VIROLOGY
2004; 78 (3): 1181-1194
Abstract
The immediate-early 63-kDa (IE63) protein of varicella-zoster virus (VZV) is a phosphoprotein encoded by open reading frame (ORF) ORF63/ORF70. To identify functional domains, 22 ORF63 mutations were evaluated for effects on IE63 binding to the major VZV transactivator, IE62, and on IE63 phosphorylation and nuclear localization in transient transfections, and after insertion into the viral genome with VZV cosmids. The IE62 binding site was mapped to IE63 amino acids 55 to 67, with R59/L60 being critical residues. Alanine substitutions within the IE63 center region showed that S165, S173, and S185 were phosphorylated by cellular kinases. Four mutations that changed two putative nuclear localization signal (NLS) sequences altered IE63 distribution to a cytoplasmic/nuclear pattern. Only three of 22 mutations in ORF63 were compatible with recovery of infectious VZV from our cosmids, but infectivity was restored by inserting intact ORF63 into each mutated cosmid. The viable IE63 mutants had a single alanine substitution, altering T171, S181, or S185. These mutants, rOKA/ORF63rev[T171], rOKA/ORF63rev[S181], and rOKA/ORF63rev[S185], produced less infectious virus and had a decreased plaque phenotype in vitro. ORF47 kinase protein and glycoprotein E (gE) synthesis was reduced, indicating that IE63 contributed to optimal expression of early and late gene products. The three IE63 mutants replicated in skin xenografts in the SCIDhu mouse model, but virulence was markedly attenuated. In contrast, infectivity in T-cell xenografts was not altered. Comparative analysis suggested that IE63 resembled the herpes simplex virus type 1 U(S)1.5 protein, which is expressed colinearly with ICP22 (U(S)1). In summary, most mutations of ORF63 made with our VZV cosmid system were lethal for infectivity. The few IE63 changes that were tolerated resulted in VZV mutants with an impaired capacity to replicate in vitro. However, the IE63 mutants were attenuated in skin but not T cells in vivo, indicating that the contribution of the IE63 tegument/regulatory protein to VZV pathogenesis depends upon the differentiated human cell type which is targeted for infection within the intact tissue microenvironment.
View details for DOI 10.1128/JVI.78.3.1181-1194.2004
View details for Web of Science ID 000188205900013
View details for PubMedID 14722273
View details for PubMedCentralID PMC321405
-
Induction of cellular and humoral immunity after aerosol or subcutaneous administration of Edmonston-Zagreb measles vaccine as a primary dose to 12-month-old children
JOURNAL OF INFECTIOUS DISEASES
2004; 189 (2): 254-257
Abstract
Infants were immunized by aerosol (10(3.6) plaque-forming units [pfu]/dose) or subcutaneous (sc) (10(4.27) pfu/dose) administration of Edmonston-Zagreb measles vaccine. Measles-specific T cell proliferative responses with a stimulation index of > or =3 developed in 72% of children given aerosol-administered vaccine, compared with 87% given s.c.-administered vaccine (P =.06). Seroconversion rates were 90% after aerosol-administered vaccine and 100% after s.c.-administered vaccine (P=.01), and measles geometric mean titers were 237 milli-international units (mIU) (95% confidence interval [CI], 146-385 mIU) and 487 mIU (95% CI, 390-609 mIU) in each group, respectively (P=.01). Measles-specific T and B cell responses were weaker after aerosol than after sc vaccination, indicating a need to use a higher aerosol dose to achieve optimal immunogenicity.
View details for Web of Science ID 000188097900012
View details for PubMedID 14722890
-
Strengthening the supply of routinely recommended vaccines in the United States - Recommendations from the National Vaccine Advisory Committee
JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION
2003; 290 (23): 3122-3128
Abstract
Between late 2000 and the spring of 2003, the United States experienced shortages of vaccines against 8 of 11 preventable diseases in children. In response, the Department of Health and Human Services requested that the National Vaccine Advisory Committee (NVAC) make recommendations on strengthening the supply of routinely recommended vaccines. The NVAC appointed a Working Group to identify potential causes of vaccine supply shortages, develop strategies to alleviate or prevent shortages, and enlist stakeholders to consider the applicability and feasibility of these strategies. The NVAC concluded that supply disruptions are likely to continue to occur. Strategies to be implemented in the immediate future include expansion of vaccine stockpiles, increased support for regulatory agencies, maintenance and strengthening of liability protections, improved communication among stakeholders, increased availability of public information, and a campaign to emphasize the benefits of vaccination. Strategies requiring further study include evaluation of appropriate financial incentives to manufacturers and streamlining the regulatory process without compromising safety or efficacy.
View details for Web of Science ID 000187277300031
View details for PubMedID 14679275
-
Requirement of Varicella-zoster virus immediate-early 4 protein for viral replication
JOURNAL OF VIROLOGY
2003; 77 (22): 12369-12372
Abstract
Varicella-zoster virus (VZV) is an alphaherpesvirus that causes two diseases, chickenpox and zoster. VZV open reading frame 4 (ORF4) encodes the immediate-early 4 (IE4) protein, which is conserved among alphaherpesvirus and has transactivation activity in transient transfections. To determine whether the ORF4 gene product is essential for viral replication, we used VZV cosmids to remove ORF4 from the VZV genome. Deleting ORF4 was incompatible with recovery of infectious virus, whereas transfections done by using repaired cosmids with ORF4 inserted at a nonnative site yielded virus. To analyze the functional domain of IE4, we introduced a mutation altering the C-terminal amino acids, KYFKC (K443S), which was designed to disrupt the dimerization of IE4 protein. Transfections with these mutant cosmids yielded no virus, indicating that this KYFKC motif was essential for IE4 function.
View details for DOI 10.1128/JVI.77.22.12369-12372.2003
View details for Web of Science ID 000186294300053
View details for PubMedID 14581575
View details for PubMedCentralID PMC254250
-
Standards for child and adolescent immunization practices
PEDIATRICS
2003; 112 (4): 958-963
View details for Web of Science ID 000185665700043
-
Measles and mumps vaccination as a model to investigate the developing immune system: passive and active immunity during the first year of life
International Symposium on Protection of Newborns through Maternal Immunization
ELSEVIER SCI LTD. 2003: 3398–3405
Abstract
Evaluations of neutralizing antibody responses in 6-, 9- and 12-month-old infants given measles or mumps vaccine indicated that 6-month-old infants had diminished humoral immune responses associated with passive antibody effects, but also had an intrinsic deficiency in antiviral antibody production, which was independent of passive antibody effects. In contrast, lower neutralizing antibody titers in 9-month-olds were related only to passive antibody effects. Measles and mumps-specific T-cell proliferation and interferon-gamma (IFNgamma) production were induced by vaccination at 6, 9 or 12 months, regardless of passive neutralizing antibodies or age. These observations suggest a need to refine concepts about passive antibody interference and primary vaccine failure, taking into account the sensitization of antiviral T-cells, which occurs in the presence of passive antibodies and is observed in infants who do not develop active humoral immunity. A second dose of measles vaccine given at 12-15 months enhanced antiviral T-cell responses to measles in infants who were vaccinated at 6 or 9 months, and produced higher seroconversion rates. Since T-cell immunity is elicited under the cover of passive antibodies, the youngest infants benefit from the synergistic protection mediated by maternal antibodies and their own capacity to develop sensitized antiviral T-cells, which prime for subsequent exposures to the viral antigens. Conceptually, maternal immunization approaches with vaccines that can be given to women of child-bearing age before pregnancy, or that are safe for administration during pregnancy, should enhance passive antibody protection. Rather than being detrimental to infant adaptive immune responses, maternal vaccination can be coupled effectively with vaccine regimens that elicit priming of antiviral immune responses in infants during the first year of life.
View details for DOI 10.1016/S0264-410X(03)00341-4
View details for PubMedID 12850348
-
Identification of CD8+ T cell epitopes in the immediate early 62 protein (IE62) of Varicella-Zoster virus, and evaluation of frequency of CD8+ T cell response to IE62, by use of IE62 peptides after varicella vaccination
JOURNAL OF INFECTIOUS DISEASES
2003; 188 (1): 40-52
Abstract
Varicella-zoster virus (VZV) causes varicella, establishes neuronal latency, and can reactivate, resulting in herpes zoster. VZV-specific T cells are important for controlling infection. VZV immediate early protein 62 (IE62) is recognized by cytotoxic T cells from immune individuals, but no CD8(+) T cell epitopes have been defined for any VZV protein. CD8(+) T cell frequencies were assessed by cytokine flow cytometry (CFC), by use of synthetic-peptide pools corresponding to the IE62 sequence. IE62 peptide-specific CD8(+) T cells were below the threshold of detection, by direct CFC of either whole blood or peripheral blood mononuclear cells (PBMCs). Activated CD8(+)CD69(+) T cells that produced interferon-gamma were detectable after in vitro restimulation of PBMCs, and restricted epitopes were identified for HLA-A*0201-positive subjects. Varicella vaccination of 3 VZV-immune subjects was associated with increases in IE62 peptide-specific CD8(+) T cells, a finding indicating that in vivo re-exposure boosts memory immunity to this important viral protein.
View details for Web of Science ID 000183905800006
View details for PubMedID 12825169
-
Construction of varicella-zoster virus recombinants from parent Oka cosmids and demonstration that ORF65 protein is dispensable for infection of human skin and T cells in the SCID-hu mouse model
JOURNAL OF VIROLOGY
2003; 77 (10): 6062-6065
Abstract
We generated an ORF65 deletion mutant by using a cosmid system constructed from the genome of a low-passage clinical isolate (P-Oka). Using the SCID-hu mouse model, we demonstrated that the ORF65 protein is dispensable for viral replication in skin and T cells, which are critical host cell targets during primary varicella-zoster virus infection.
View details for DOI 10.1128/JVI.77.10.6062-6065.2003
View details for Web of Science ID 000182631100052
View details for PubMedID 12719598
View details for PubMedCentralID PMC154042
-
Differentiation of varicella-zoster virus ORF47 protein kinase and IE62 protein binding domains and their contributions to replication in human skin xenografts in the SCID-hu mouse
JOURNAL OF VIROLOGY
2003; 77 (10): 5964-5974
Abstract
To investigate the role of the ORF47 protein kinase of varicella-zoster virus (VZV), we constructed VZV recombinants with targeted mutations in conserved motifs of ORF47 and a truncated ORF47 and characterized these mutants for replication, phosphorylation, and protein-protein interactions in vitro and for infectivity in human skin xenografts in the SCID-hu mouse model in vivo. Previous experiments showed that ROka47S, a null mutant that makes no ORF47 protein, did not replicate in skin in vivo (J. F. Moffat, L. Zerboni, M. H. Sommer, T. C. Heineman, J. I. Cohen, H. Kaneshima, and A. M. Arvin, Proc. Natl. Acad. Sci. USA 95:11969-11974, 1998). The construction of VZV recombinants with targeted ORF47 mutations made it possible to assess the effects on VZV infection of human skin xenografts of selectively abolishing ORF47 protein kinase activity. ORF47 mutations that resulted in a C-terminal truncation or disrupted the DYS kinase motif eliminated ORF47 kinase activity and were associated with extensive nuclear retention of ORF47 and IE62 proteins in vitro. Disrupting ORF47 kinase function also resulted in a marked decrease in VZV replication and cutaneous lesion formation in skin xenografts in vivo. However, infectivity in vivo was not blocked completely as long as the capacity of ORF47 protein to bind IE62 protein was preserved, a function that we identified and mapped to the N-terminal domain of ORF47 protein. These experiments indicate that ORF47 kinase activity is of critical importance for VZV infection and cell-cell spread in human skin in vivo but suggest that it is the formation of complexes between ORF47 and IE62 proteins, both VZV tegument components, that constitutes the essential contribution of ORF47 protein to VZV replication in vivo.
View details for DOI 10.1128/JVI.77.10.5964-5974.2003
View details for Web of Science ID 000182631100042
View details for PubMedID 12719588
View details for PubMedCentralID PMC154036
-
Mutational analysis of open reading frames 62 and 71, encoding the Varicella-Zoster virus immediate-early transactivating protein, IE62, and effects on replication in vitro and in skin xenografts in the SCID-hu mouse in vivo
JOURNAL OF VIROLOGY
2003; 77 (10): 5607-5620
Abstract
The varicella-zoster virus (VZV) genome has unique long (U(L)) and unique short (U(S)) segments which are flanked by internal repeat (IR) and terminal repeat (TR) sequences. The immediate-early 62 (IE62) protein, encoded by open reading frame 62 (ORF62) and ORF71 in these repeats, is the major VZV transactivating protein. Mutational analyses were done with VZV cosmids generated from parent Oka (pOka), a low-passage clinical isolate, and repair experiments were done with ORF62 from pOka and vaccine Oka (vOka), which is derived from pOka. Transfections using VZV cosmids from which ORF62, ORF71, or the ORF62/71 gene pair was deleted showed that VZV replication required at least one copy of ORF62. The insertion of ORF62 from pOka or vOka into a nonnative site in U(S) allowed VZV replication in cell culture in vitro, although the plaque size and yields of infectious virus were decreased. Targeted mutations in binding sites reported to affect interaction with IE4 protein and a putative ORF9 protein binding site were not lethal. Single deletions of ORF62 or ORF71 from cosmids permitted recovery of infectious virus, but recombination events repaired the defective repeat region in some progeny viruses, as verified by PCR and Southern hybridization. VZV infectivity in skin xenografts in the SCID-hu model required ORF62 expression; mixtures of single-copy recombinant Oka Delta 62 (rOka Delta 62) or rOka Delta 71 and repaired rOka generated by recombination of the single-copy deletion mutants were detected in some skin implants. Although insertion of ORF62 into the nonnative site permitted replication in cell culture, ORF62 expression from its native site was necessary for cell-cell spread in differentiated human skin tissues in vivo.
View details for DOI 10.1128/JVI.77.10.5607-5620.2003
View details for Web of Science ID 000182631100007
View details for PubMedID 12719553
View details for PubMedCentralID PMC154054
-
Deficient cytomegalovirus-specific Th1 responses in young children with urine virus shedding
90th Annual Meeting of the American-Association-for-Immunologists
FEDERATION AMER SOC EXP BIOL. 2003: C301–C301
View details for Web of Science ID 000182367001403
-
Long term antiviral suppression after treatment for neonatal herpes infection
PEDIATRIC INFECTIOUS DISEASE JOURNAL
2003; 22 (4): 371-372
View details for Web of Science ID 000182327600014
View details for PubMedID 12690281
-
Analysis of the frequencies and of the memory T cell phenotypes of human CD8(+) T cells specific for influenza A viruses
JOURNAL OF INFECTIOUS DISEASES
2003; 187 (7): 1075-1084
Abstract
We characterized the human CD8+ T cell response against influenza A viruses by a flow cytometry-based assay. Peripheral blood mononuclear cells (PBMCs) were incubated with inactivated influenza virus preparation, for 17 h, and were stained for intracellular interferon-gamma. Major histocompatibility complex class I-restricted memory CD8+ T cells specific for influenza antigens were detected in PBMCs from all 19 adult donors, at an average frequency of 0.39%. On average, 83% of influenza virus-specific CD8+ T cells expressed the differentiation-associated marker CD27, a percentage that is significantly higher than that of CD8+ T cells specific for pp65 of human cytomegalovirus (53%). These observations indicate that class I-restricted immunity against influenza A viruses is characterized by the persistence, after clearance of infection, of circulating antigen-specific CD8+ T cells. The different patterns of CD27 expression in influenza virus- and cytomegalovirus-specific CD8+ T cells suggest that influenza virus-specific memory and effector CD8+ T cells can be differentiated by phenotypic analysis.
View details for Web of Science ID 000181713000007
View details for PubMedID 12660922
-
Microarray analysis of host cell gene transcription in response to varicella-zoster virus infection of human T cells and fibroblasts in vitro and SCIDhu skin xenografts in vivo
JOURNAL OF VIROLOGY
2003; 77 (2): 1268-1280
Abstract
During primary infection, varicella-zoster virus (VZV) is spread via lymphocytes to skin, where it induces a rash and establishes latency in sensory ganglia. A live, attenuated varicella vaccine (vOka) was generated by using the VZV Oka strain (pOka), but the molecular basis for vOka attenuation remains unknown. Little is known concerning the effects of wild-type or attenuated VZV on cellular gene regulation in the host cells that are critical for pathogenesis. In this study, transcriptional profiles of primary human T cells and fibroblasts infected with VZV in cell culture were determined by using 40,000-spot human cDNA microarrays. Cellular gene transcription in human skin xenografts in SCID mice that were infected with VZV in vivo was also evaluated. The profiles of cellular gene transcripts that were induced or inhibited in infected human foreskin fibroblasts (HFFs), T cells, and skin in response to pOka and vOka infection were similar. However, significant alterations in cellular gene regulation were observed among the three differentiated human cell types that were examined, suggesting specific differences in the biological consequences of VZV infection related to the target cell. Changes in cellular gene transcription detected by microarray analysis were confirmed for selected genes by quantitative real-time reverse transcription-PCR analysis of VZV-infected cells. Interestingly, the transcription of caspase 8 was found to be decreased in infected T cells but not in HFFs or skin, which may signify a tissue-specific antiapoptosis mechanism. The use of microarrays to demonstrate differences in effects on host cell genes in primary, biologically relevant cell types provides background information for experiments to link these various response phenotypes with mechanisms of VZV pathogenesis that are important for the natural course of human infection.
View details for DOI 10.1128/JVI.77.2.1268-1280.2003
View details for Web of Science ID 000180166600048
View details for PubMedID 12502844
View details for PubMedCentralID PMC140848
-
Varicella-zoster virus infection facilitates VZV glycoprotein E trafficking to the membrane surface of melanoma cells.
Journal of medical virology
2003; 70: S56-8
Abstract
Varicella-zoster virus glycoprotein E (gE) is the most abundant VZV glycoprotein on the surface of virus-infected cells. VZV gE has targeting sequences for the trans-Golgi network (TGN) and is transported from the ER to the TGN in infected and gE-transfected cells. In this study, VZV gE expressing melanoma cell lines were generated. gE is expressed under the control of the reverse Tet repressor (Tet-On). gE induced by Tet-On is retained at the ER as well as in the cis Golgi by immunofluorescence confocal microscopy. To test whether other viral protein(s) may facilitate gE trafficking and surface localization, MSPgE-vOka virus that contains MSPgE in place of wt gE was made. MAb 3B3 anti-gE does not bind to MSPgE. This MAb was used to track the localization of gE in Met-gE cells post MSPgE-vOka infection. gE became detectable mostly at the TGN and on the cell surface after viral infection. These data indicate that viral proteins facilitate the trafficking and cell surface expression of gE.
View details for PubMedID 12627489
-
Promoter sequences of varicella-zoster virus glycoprotein I targeted by cellular transactivating factors Sp1 and USF determine virulence in skin and T cells in SCIDhu mice in vivo
JOURNAL OF VIROLOGY
2003; 77 (1): 489-498
Abstract
Varicella-zoster virus (VZV) glycoprotein I is dispensable in cell culture but necessary for infection of human skin and T cells in SCIDhu mice in vivo. The gI promoter contains an activating upstream sequence that binds the cellular transactivators specificity factor 1 (Sp1) and upstream stimulatory factor (USF) and an open reading frame 29 (ORF29)-responsive element (29RE), which mediates enhancement by ORF29 DNA binding protein of immediate-early 62 (IE62)-induced transcription. Recombinants, rOKAgI-Sp1 and rOKAgI-USF, with two base pair substitutions in Sp1 or USF sites, replicated like rOKA in vitro, but infectivity of rOKAgI-Sp1 was significantly impaired in skin and T cells in vivo. A double mutant, rOKAgI-Sp1/USF, did not replicate in skin but yielded low titers of infectious virus in T cells. The repaired protein, rOKAgI:rep-Sp1/USF, was as infectious as rOKA. Thus, disrupting gI promoter sites for cellular transactivators altered VZV virulence in vivo, with variable consequences related to the cellular factor and the host cell type. Mutations in the 29RE of the gI promoter were made by substituting each of four 10-bp blocks in this region with a 10-bp sequence, GATAACTACA, that was predicted to interfere with enhancer effects of the ORF29 protein. One of these mutants, which was designated rOKAgI-29RE-3, had diminished replication in skin and T cells, indicating that ORF29 protein-mediated enhancement of gI expression contributes to VZV virulence. Mutations within promoters of viral genes that are nonessential in vitro should allow construction of recombinant herpesviruses that have altered virulence in specific host cells in vivo and may be useful for designing herpesviral gene therapy vectors and attenuated viral vaccines.
View details for DOI 10.1128/JVI.77.1.489-498.2003
View details for Web of Science ID 000179855400050
View details for PubMedID 12477854
View details for PubMedCentralID PMC140613
-
The requirement of varicella zoster virus glycoprotein E (gE) for viral replication and effects of glycoprotein I on gE in melanoma cells
VIROLOGY
2002; 304 (2): 176-186
Abstract
The glycoprotein E (gE) of varicella zoster virus (VZV), encoded by ORF68, is the most abundant viral glycoprotein. In the current experiments, we demonstrated that ORF68 deletion was incompatible with recovery of infectious virus from VZV cosmids. Replacing ORF68 at a nonnative AvrII site in the genome restored infectivity. Further, we found that VZV gE could be expressed under the control of the Tet-On promoter in stably transfected melanoma cell lines (Met-gE cells) without evidence of toxicity. In these Met-gE cells, gE colocalized with gamma-adaptin, a trans Golgi network marker, in perinuclear sites, but did not reach plasma membranes. In order to investigate how infection altered gE localization, we made a recombinant virus, vOka-MSPgE, with ORF68 from the VZV MSP strain. VZV MSP encodes a mutant gE protein (D150N) that lacks the mAb epitope, 3B3 (Santos et al., Virology 275, 306-317, 2000), whereas Met-gE protein binds mAb 3B3. Within 48 h after Met-gE cells were infected with vOka-MSPgE, the steady-state distribution of Met-gE protein extended beyond the perinuclear areas to other cytoplasmic sites and to plasma membranes. A second recombinant, vOka-MSPgE without gI (vOka-MSPgEdeltagI), was constructed to investigate Met-gE protein distribution in the absence of gI. The redistribution of Met-gE protein which was observed by 48 h after vOka-MSPgE infection did not occur until 5 days (140 h) within vOka-MSPgEdeltagI infected cells. After vOka-MSPgE infection of Met-gE cells, most Met-gE protein was in the final 94K mature form by 72 h. However, progression to predominance of mature gE was delayed in Met-gE cells infected with vOka-MSPgEdeltagI. These observations confirm our hypothesis that VZV gE is essential, based upon the demonstration of restored infectivity after replacing ORF68 in a nonnative site in the genome, and provide further evidence of the role of gI in facilitating the maturation and intracellular distribution of this critical VZV glycoprotein.
View details for DOI 10.1006/viro.2002.1556
View details for Web of Science ID 000180060400005
View details for PubMedID 12504560
-
Tropism of varicella-zoster virus for human tonsillar CD4(+) T lymphocytes that express activation, memory, and skin homing markers
JOURNAL OF VIROLOGY
2002; 76 (22): 11425-11433
Abstract
Varicella-zoster virus (VZV) is an alphaherpesvirus with the characteristic neurotropism of this group, but VZV also infects T cells productively and downregulates major histocompatibility complex (MHC) class I expression on infected T cells, as shown in the SCID-hu mouse model. T-cell tropism is likely to be critical for the cell-associated viremia associated with primary VZV infection. In these experiments, we found that VZV infects human tonsillar CD4(+) T cells in culture, with 15 to 25% being positive for VZV proteins as detected by polyclonal anti-VZV immunoglobulin G (IgG) staining and monitored by flow cytometry analysis. RNA transcripts for VZV gE, a late gene product, were detected in T-cell populations that expressed VZV surface proteins, but not in the VZV-negative cell fraction. Exposure to phorbol myristate acetate resulted in an increase in VZV-positive T cells, indicating that viral DNA was present within these cells and that VZV gene expression could be induced by T-cell activation. By immune scanning electron microscopy, VZV virions were detected in abundance on the surfaces of infected tonsillar T cells. The predominant CD4(+) T-lymphocyte subpopulations that became infected were activated CD69(+) T cells with the CD45RA(-) memory phenotype. Subsets of CD4(+) T cells that expressed skin homing markers, cutaneous leukocyte antigen, and chemokine receptor 4 were also infected with VZV. By chemotaxis assay, VZV-infected T cells migrated to SDF-1, demonstrating that skin migratory function was intact despite VZV infection. The susceptibility of tonsil T cells to VZV suggests that these cells may be important targets during the initial VZV infection of upper respiratory tract sites. Viral transfer to migrating T cells in the tonsils may facilitate cell-associated viremia, and preferential infection of CD4 T cells that express skin homing markers may enhance VZV transport to cutaneous sites of replication.
View details for DOI 10.1128/JVI.76.22.11425-11433.2002
View details for Web of Science ID 000178822400027
View details for PubMedID 12388703
View details for PubMedCentralID PMC136789
-
Latent cytomegalovirus down-regulates major histocompatibility complex class II expression on myeloid progenitors
BLOOD
2002; 100 (8): 2867-2873
Abstract
Following primary infection, human cytomegalovirus (CMV) establishes a lifelong latent infection in bone marrow-derived myeloid lineage cells. Although downmodulation of major histocompatibility complex (MHC) class I and class II protein levels occurs during active viral replication, little is known about the modulation of these proteins during latent infection. When analyzed by flow cytometry, latently infected adherent cells collected from granulocyte macrophage progenitor (GM-P) cultures exhibited a striking reduction in MHC class II antigen present on the cell surface starting very early after exposure to virus that continued for more than 2 weeks. In comparison, cell surface levels of the monocyte cell surface marker CD14 remained unaltered in these cells. A recombinant virus (RV798) lacking the virus genes US2-US11 retained the ability to downmodulate MHC class II levels during latent infection. Immunoblot and immunofluorescent antibody staining analyses showed that the reduction in MHC class II surface levels during latency was associated with a block in protein trafficking. HLA-DR was retained within cytoplasmic vesicles that also contained HLA-DM. Thus, downmodulation remained independent of all previously characterized MHC class I and class II immunomodulatory viral gene products and involved a mechanism not previously ascribed to any viral function. These data show that latent infection is accompanied by reduced cell surface expression of MHC class II proteins, a strategy that would afford the virus escape from immunosurveillance and increase the chances for lifelong latent infection.
View details for Web of Science ID 000178519100030
View details for PubMedID 12351397
-
The molecular epidemiology of varicella-zoster virus: Evidence for geographic segregation
26th International Herpesvirus Workshop
OXFORD UNIV PRESS INC. 2002: 888–94
Abstract
Of 75 varicella-zoster virus (VZV) isolates obtained from patients in Africa, Asia, and the Far East, 74 (98.6%) were found to be positive for a BglI restriction site in gene 54. By contrast, <22% of strains from patients in the United Kingdom and in North and South America were positive for the BglI restriction site. Viruses positive for BglI were significantly more common in zoster occurring in patients of nonwhite origin (P<.05). Irrespective of the country in which the sample was obtained, 98% of strains positive for BglI clustered within a single phylogenetic group, which we termed "group A"; the exception was 1 strain that appeared to be recombinant genotype C/A. We used the BglI site to examine both the spread of type A viruses in the United Kingdom and the patterns of VZV infections within persons from different ethnic groups who grew up in the United Kingdom or abroad.
View details for Web of Science ID 000177991100002
View details for PubMedID 12232828
-
Glycoprotein I of Varicella-zoster virus is required for viral replication in skin and T cells
JOURNAL OF VIROLOGY
2002; 76 (16): 8468-8471
Abstract
Varicella-zoster virus (VZV) glycoprotein I (gI) is dispensable in cell culture; the SCIDhu model of VZV pathogenesis was used to determine whether gI is necessary in vivo. The parental and repaired viruses grew in human skin and thymus/liver implants, but the gI deletion mutant was not infectious. Thus, gI is essential for VZV infectivity in skin and T cells.
View details for DOI 10.1128/JVI.16.8468-8471.2002
View details for Web of Science ID 000177049500055
View details for PubMedID 12134050
View details for PubMedCentralID PMC155157
-
Use of an inactivated varicella vaccine in recipients of hematopoietic-cell transplants
NEW ENGLAND JOURNAL OF MEDICINE
2002; 347 (1): 26-34
Abstract
The reactivation of varicella-zoster virus from latency causes zoster and is common among recipients of hematopoietic-cell transplants.We randomly assigned patients who were scheduled to undergo autologous hematopoietic-cell transplantation for non-Hodgkin's or Hodgkin's lymphoma to receive varicella vaccine or no vaccine. Heat-inactivated, live attenuated varicella vaccine was given within 30 days before transplantation and 30, 60, and 90 days after transplantation. The patients were monitored for zoster and for immunity against varicella-zoster virus for 12 months.Of the 119 patients enrolled, 111 received a transplant. Zoster developed in 7 of 53 vaccinated patients (13 percent) and in 19 of 58 unvaccinated patients (33 percent) (P=0.01). After two patients in whom zoster developed before transplantation were excluded, the respective rates were 13 percent and 30 percent (P=0.02). In vitro CD4 T-cell proliferation in response to varicella-zoster virus (expressed as the mean stimulation index) was greater in patients who received the vaccine than in those who did not at 90 days, after three doses (P=0.04); at 120 days, after all four doses (P<0.001); at 6 months (P=0.004); and at 12 months (P=0.02). The risk of zoster was reduced for each unit increase in the stimulation index above 1.6; a stimulation index above 5.0 correlated with greater than 93 percent protection. Induration, erythema, or local pain at the injection site was observed in association with 10 percent of the doses.Inactivated varicella vaccine given before hematopoietic-cell transplantation and during the first 90 days thereafter reduces the risk of zoster. The protection correlates with reconstitution of CD4 T-cell immunity against varicella-zoster virus.
View details for PubMedID 12097537
-
Debate: the argument against. Should all pregnant women be offered type-specific serological screening for HSV infection?
Herpes : the journal of the IHMF
2002; 9 (2): 48-50
Abstract
The first goal in minimizing herpes simplex virus (HSV) mortality and morbidity in infants is to reduce the risk of acquisition of new infections during pregnancy, especially in late gestation. Antenatal testing does not necessarily predict the risk of transmission to the newborn infant, since this risk is variable. In order to identify newly acquired infection in women who are HSV-seronegative, repeat testing in late pregnancy would need to be offered. In those who are HSV-seropositive, concern for transmission to the infant is likely to result in administration of antiviral drugs to the mother or in Caesarean delivery. The potential consequence is medical intervention for many pregnancies that would not have been complicated by perinatal HSV transmission. Risk - and cost-benefit analyses are needed to assess HSV type-specific serological screening of pregnant women. Practical benefit can be achieved by counselling all pregnant women against oral or unprotected sexual contact during pregnancy.
View details for PubMedID 12106512
-
Varlirix (GlaxoSmithKline).
Current opinion in investigational drugs
2002; 3 (7): 996-999
Abstract
GlaxoSmithKline (formerly SmithKline Beecham) has developed and launched Varilrix, a preparation of live, attenuated Oka-strain varicella zoster virus, for immunization against varicella zoster infections [455138]. By the end of 1998, Varilrix was available in a few European countries and in India [284490], [455138]. By 2001, the vaccine was also available in Brazil and Hong Kong [396267].
View details for PubMedID 12186278
-
Memory cytotoxic T cell responses to viral tegument and regulatory proteins encoded by open reading frames 4, 10, 29, and 62 of varicella-zoster virus
VIRAL IMMUNOLOGY
2002; 15 (3): 507-516
Abstract
Cytotoxic T cell recognition of tegument and regulatory proteins encoded by open reading frames (ORFs) 4, 10, 29, and 62 of varicella-zoster virus (VZV) was evaluated using limiting dilution conditions to estimate the precursor frequencies of memory T cells specific for these proteins in immune subjects. Responder cell frequencies for ORFs 4, 10, and 62 gene products, which are virion tegument components and function as immediate early viral transactivating proteins, were equivalent. CTLp recognition of VZV proteins made in latently infected cells, which include ORF4 and ORF62 proteins, was not maintained preferentially when compared to ORF10 protein, which has not been shown to be expressed during latency. T cell recognition of ORF29 protein, the major DNA binding protein, which is expressed during replication but not incorporated into the virion tegument, was less common than responses to ORFs 4, 10, and 62 gene products. Older individuals had diminished numbers of memory CTLp that lysed autologous targets expressing IE62 protein; these responses were increased after immunization with live attenuated varicella vaccine to the range observed in younger adults. Adaptive immunity to VZV is characterized by a broad repertoire of memory CTL responses to proteins that comprise the virion tegument and regulate viral gene expression in infected cells.
View details for Web of Science ID 000178294800011
View details for PubMedID 12479399
-
Antiviral therapy for varicella and herpes zoster.
Seminars in pediatric infectious diseases
2002; 13 (1): 12-21
Abstract
Varicella-zoster virus (VZV) causes 2 clinical illnesses, varicella (chickenpox) and herpes zoster (shingles). The purpose of this review is to describe the role of antiviral therapy in the treatment of VZV infections in healthy and immunocompromised children. Acyclovir is the drug of choice for varicella and herpes zoster. The route of administration may be intravenous or oral, depending on the immunocompetence of the host. The clinical impact of acyclovir therapy is related directly to its use early in the clinical course and to the likely susceptibility of the patient to severe or life-threatening VZV infection. Patients who have the most clinical benefit are otherwise healthy adolescents with varicella infection and high-risk populations of immunocompromised children who have varicella or herpes zoster. The morbidity and mortality of VZV infections are reduced substantially by initiating acyclovir treatment early in the course of the disease.
View details for PubMedID 12118839
-
Immune responses to measles and mumps vaccination of infants at 6, 9, and 12 months
38th Annual Meeting of the Infectious-Diseases-Society-of-America
UNIV CHICAGO PRESS. 2001: 817–26
Abstract
Immunizing infants against measles at the youngest age possible has the potential to reduce morbidity and mortality. The ability of infants at 6, 9, or 12 months to respond to measles and mumps vaccines was evaluated by measuring T cell proliferation, interferon-gamma production, and neutralizing antibody titers before and after vaccination. Infants in all age groups had equivalent cellular immune responses to measles or mumps viruses, with or without passive antibodies when immunized. In contrast, 6-month-old infants without passive antibodies had low geometric mean titers of antibody to measles or mumps viruses and low seroconversion rates. Geometric mean titers of antibody to measles virus increased if infants were revaccinated at 12 months. Six-month-old infants had limited humoral responses to paramyxovirus vaccines, whereas cellular immunity was equivalent to that of older infants. T cell responses can be established by immunization with these live attenuated virus vaccines during the first year, despite the presence of passive antibodies.
View details for Web of Science ID 000171228400002
View details for PubMedID 11528592
-
Quanitation of CD4+responder T cell frequencies to measles in vaccinated infants and adults
OXFORD UNIV PRESS INC. 2001: 1152–52
View details for Web of Science ID 000171226900400
-
Mutational analysis of the repeated open reading frames, ORFs 63 and 70 and ORFs 64 and 69, of varicella-zoster virus
JOURNAL OF VIROLOGY
2001; 75 (17): 8224-8239
Abstract
Varicella-zoster virus (VZV) open reading frame 63 (ORF63), located between nucleotides 110581 and 111417 in the internal repeat region, encodes a nuclear phosphoprotein which is homologous to herpes simplex virus type 1 (HSV-1) ICP22 and is duplicated in the terminal repeat region as ORF70 (nucleotides 118480 to 119316). We evaluated the role of ORFs 63 and 70 in VZV replication, using recombinant VZV cosmids and PCR-based mutagenesis to make single and dual deletions of these ORFs. VZV was recovered within 8 to 10 days when cosmids with single deletions were transfected into melanoma cells along with the three intact VZV cosmids. In contrast, VZV was not detected in transfections carried out with a dual deletion cosmid. Infectious virus was recovered when ORF63 was cloned into a nonnative AvrII site in this cosmid, confirming that failure to generate virus was due to the dual ORF63/70 deletion and that replication required at least one gene copy. This requirement may be related to our observation that ORF63 interacts directly with ORF62, the major immediate-early transactivating protein of VZV. ORF64 is located within the inverted repeat region between nucleotides 111565 and 112107; it has some homology to the HSV-1 Us10 gene and is duplicated as ORF69 (nucleotides 117790 to 118332). ORF64 and ORF69 were deleted individually or simultaneously using the VZV cosmid system. Single deletions of ORF64 or ORF69 yielded viral plaques with the same kinetics and morphology as viruses generated with the parental cosmids. The dual deletion of ORF64 and ORF69 was associated with an abnormal plaque phenotype characterized by very large, multinucleated syncytia. Finally, all of the deletion mutants that yielded recombinants retained infectivity for human T cells in vitro and replicated efficiently in human skin in the SCIDhu mouse model of VZV pathogenesis.
View details for Web of Science ID 000170343900047
View details for PubMedID 11483768
View details for PubMedCentralID PMC115067
-
Natural history of neonatal herpes simplex virus infections in the acyclovir era
PEDIATRICS
2001; 108 (2): 223-229
Abstract
During the 2 decades in which effective antiviral therapies have been available for neonatal herpes simplex virus (HSV) disease, changes have been documented not only in the outcomes of infected infants, but also in the natural history of the disease itself. Numerous studies previously have reported that early institution of antiviral therapy is beneficial to the outcome of the disease. The objective of this study was to provide an update of neonatal HSV disease to identify means by which future improvements in the management of HSV-infected neonates can be made.Neonates enrolled in 2 studies of parenteral acyclovir for the treatment of neonatal HSV disease provided the data source. The National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group conducted the studies between 1981 and 1997. A total of 186 patients are summarized, all of whom were treated with acyclovir. Demographic and clinical characteristics of these patients are reported.Comparisons between patients treated in the periods between 1981-1988 and 1989-1997 according to extent of disease revealed that the mean time between the onset of disease symptoms and initiation of therapy has not changed significantly from the early 1980s to the late 1990s. Of all patients evaluated, 40% had fetal scalp monitors during the delivery process. A significant minority of patients did not have skin vesicles at the time of their presentation and did not develop them during the acute HSV disease (39% of patients with disseminated disease; 32% of patients with central nervous system [CNS] disease; and 17% of patients with skin, eye, and/or mouth disease). Among patients with CNS disease, mortality was associated with prematurity. Among patients with disseminated HSV disease treated with acyclovir at 30 mg/kg/d, mortality was associated with aspartate transaminase elevations of >/=10 times the upper limit of normal at the time of initiation of acyclovir therapy. Mortality was also associated with lethargy at initiation of antiviral therapy for patients with disseminated disease. Patients' morbidity status was associated with the extent of disease (skin, eye, and/or mouth disease vs CNS vs disseminated). For those patients with CNS disease, morbidity was also associated with seizures at initiation of antiviral therapy.Data presented in the current comparison of neonatal HSV disease over the 2 periods (1981-1988 vs 1989-1997) demonstrate that no progress has been made in decreasing the interval between onset of HSV symptoms and initiation of antiviral therapy. Additional strides in the improvement of disease outcome may occur only if the interval between onset of symptoms and initiation of therapy is shortened. The means by which this will be accomplished lie in increased consideration of neonatal HSV infections in acutely ill infants. Specific data and recommendations to facilitate this goal are contained within.
View details for Web of Science ID 000170211800021
View details for PubMedID 11483781
-
Varicella-zoster virus: molecular virology and virus-host interactions
CURRENT OPINION IN MICROBIOLOGY
2001; 4 (4): 442-449
Abstract
Cosmid-based mutagenesis and methods to examine varicella-zoster virus (VZV) tropism for differentiated human cells in vivo provide new information about molecular mechanisms of VZV infection. How specific VZV gene products contribute to viral replication has been further defined, and effects of VZV on expression of cellular genes have been demonstrated.
View details for Web of Science ID 000170458000015
View details for PubMedID 11495809
-
Safety and efficacy of high-dose intravenous acyclovir in the management of neonatal herpes simplex virus infections
PEDIATRICS
2001; 108 (2): 230-238
Abstract
The objective of this investigation was to establish the safety of high-dose (HD) acyclovir for the treatment of neonatal herpes simplex virus (HSV) disease. In addition, an estimate of therapeutic efficacy was sought, both with respect to mortality and to morbidity. Virologic efficacy of HD acyclovir was also assessed.Infants who were =28 days old and whose disease was considered to be caused by HSV were enrolled in this study. Patients with central nervous system (CNS; N = 28) or disseminated (N = 41) HSV infection were offered participation in the trial. A small number of patients with HSV disease limited to the skin, eyes, or mouth (SEM; N = 10) or whose disease was clinically consistent with HSV but who did not have virologic confirmation of infection (N = 9) also were enrolled on a compassionate basis. Only patients with virologically confirmed HSV disease were included in efficacy analyses. All enrolled patients were included in safety analyses.The study was an open-label evaluation of intravenous acyclovir at dosages higher than the 30 mg/kg/d standard dosage approved by the US Food and Drug Administration. The first 16 patients enrolled received intermediate-dose (ID) acyclovir (45 mg/kg/d), and the next 72 patients received HD acyclovir (60 mg/kg/d). Acyclovir was administered in 3 divided daily doses for 21 days. Neonates were assessed prospectively throughout treatment and at scheduled follow-up visits for the first 4 years of life. Data were compared with those of a previous National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group trial in which patients received standard-dose (SD) acyclovir for 10 days and in which identical methods (with the exception of acyclovir dosage and duration of therapy) were used.Six (21%) of 29 HD acyclovir recipients whose HSV disease remained localized to the SEM or CNS experienced neutropenia. One of the 6 had an absolute neutrophil count <500/mm(3), and 5 patients had an absolute neutrophil count (ANC) between 500/mm(3) and 1000/mm(3). In all 6 cases, the ANC recovered during continuation of acyclovir at the same dosage or after completion of acyclovir therapy, and there were no apparent adverse sequelae of the transient neutropenia. No other drug-related adverse events were reported among ID or HD recipients, and no other laboratory aberrations could be correlated specifically with antiviral therapy. The survival rate for the patients with disseminated HSV disease treated with HD acyclovir was significantly higher than for those in the previous study treated with SD acyclovir, with an odds ratio (OR) of 3.3 (95% confidence interval [CI]: 1.4-7.9). For patients with CNS disease, however, survival rates were similar for the HD and SD groups. To assess the effect of HD acyclovir on survival for the entire population with neonatal HSV disease, the Cox proportional hazards regression analysis was performed with stratification for disease category (CNS versus disseminated). In performing this analysis, differences in mortality for each disease category were weighted to allow statistical comparison of the treatment dosage groups (HD, ID, and SD). This analysis indicated that the survival rate for patients treated with HD acyclovir was statistically significantly higher than for patients treated with SD acyclovir (OR: 3.3; 95% CI: 1.5-7.3). Recipients of HD acyclovir had a borderline significant decrease in morbidity compared with SD recipients, after stratification for the extent of disease (SEM vs CNS vs disseminated) and controlling for the potential confounding factors of HSV type (HSV-1 vs. HSV-2), prematurity, and disease severity (seizures). Patients treated with HD acyclovir were 6.6 times (adjusted OR; 95% CI: 0.8-113.6) as likely to be developmentally normal at 12 months of age as patients treated with SD therapy.These data support the use of a 21-day course of HD (60 mg/kg/d) intravenous acyclovir to treat neonatal CNS and disseminated HSV disease. Throughout the course of HD acyclovir therapy, serial ANC determination should be made at least twice weekly. Decreasing the acyclovir dosage or administering granulocyte colony-stimulating factor should be considered if the ANC remains below 500/mm(3) for a prolonged period.
View details for Web of Science ID 000170211800022
View details for PubMedID 11483782
-
Varicella vaccine: Genesis, efficacy, and attenuation
VIROLOGY
2001; 284 (2): 153-158
View details for Web of Science ID 000169242300001
View details for PubMedID 11384215
-
Varicella-zoster virus retains major histocompatibility complex class I proteins in the Golgi compartment of infected cells
JOURNAL OF VIROLOGY
2001; 75 (10): 4878-4888
Abstract
We sought to examine the effects of varicella-zoster virus (VZV) infection on the expression of major histocompatibility complex class I (MHC I) molecules by human fibroblasts and T lymphocytes. By flow cytometry, VZV infection reduced the cell surface expression of MHC I molecules on fibroblasts significantly, yet the expression of transferrin receptor was not affected. Importantly, when human fetal thymus/liver implants in SCID-hu mice were inoculated with VZV, cell surface MHC I expression was downregulated specifically on VZV-infected human CD3+ T lymphocytes, a prominent target that sustains VZV viremia. The stage in the MHC I assembly process that was disrupted by VZV in fibroblasts was examined in pulse-chase and immunoprecipitation experiments in the presence of endoglycosidase H. MHC I complexes continued to be assembled in VZV-infected cells and were not retained in the endoplasmic reticulum. In contrast, immunofluorescence and confocal microscopy showed that VZV infection resulted in an accumulation of MHC I molecules which colocalized to the Golgi compartment. Inhibition of late viral gene expression by treatment of infected fibroblasts with phosphonoacetic acid did not influence the modulation of MHC I expression, nor did transfection of cells with plasmids expressing immediate early viral proteins. However, cells transfected with a plasmid carrying the early gene ORF66 did result in a significant downregulation of MHC I expression, suggesting that this gene encodes a protein with an immunomodulatory function. Thus, VZV downregulates MHC I expression by impairing the transport of MHC I molecules from the Golgi compartment to the cell surface; this effect may enable the virus to evade CD8+ T-cell immune recognition during VZV pathogenesis, including the critical phase of T-lymphocyte-associated viremia.
View details for Web of Science ID 000168309300043
View details for PubMedID 11312359
View details for PubMedCentralID PMC114242
-
Varicella vaccine - The first six years.
NEW ENGLAND JOURNAL OF MEDICINE
2001; 344 (13): 1007-1009
View details for Web of Science ID 000167716600010
View details for PubMedID 11274629
-
Immune evasion as a pathogenic mechanism of varicella zoster virus
SEMINARS IN IMMUNOLOGY
2001; 13 (1): 27-39
Abstract
Varicella zoster virus (VZV) is a human herpesvirus that causes varicella (chickenpox) during primary infection, establishes latency in dorsal root ganglia and may reactivate years later, producing herpes zoster. VZV must evade antiviral immunity during three important stages of viral pathogenesis, including the cell-associated viremia characteristic of primary infection, persistence in dorsal root ganglia during latency and the initial period of VZV reactivation. Our observations about the immunomodulatory effects of VZV document its capacity to interfere with adaptive immunity mediated by CD4 as well as CD8 T cells, ensuring the survival of the virus in the human population from generation to generation.
View details for DOI 10.1006/smim.2001.0293
View details for Web of Science ID 000168146200004
View details for PubMedID 11289797
-
Granulysin blocks replication of varicella-zoster virus and triggers apoptosis of infected cells
VIRAL IMMUNOLOGY
2001; 14 (2): 125-133
Abstract
Granulysin, a lytic protein present in cytolytic granules of human natural killer and cytotoxic T cells, entered cells infected with varicella-zoster virus (VZV). Exposure to granulysin accelerated death of infected cells as assessed by apoptosis markers. The functional domain of granulysin that mediated its antiviral effects was amino acid 23-51; this domain also mediates the additional antitumor cell effects of granulysin. Because granulysin is a product of natural killer cells and T lymphocytes, it is possible that its antiviral activity may act as a mediator of innate and adaptive immune mechanisms.
View details for Web of Science ID 000168993100005
View details for PubMedID 11398808
-
Essential role played by the C-terminal domain of glycoprotein I in envelopment of varicella-zoster virus in the trans-Golgi network: Interactions of glycoproteins with tegument
JOURNAL OF VIROLOGY
2001; 75 (1): 323-340
Abstract
Varicella-zoster virus (VZV) is enveloped in the trans-Golgi network (TGN). Here we report that glycoprotein I (gI) is required within the TGN for VZV envelopment. Enveloping membranous TGN cisternae were microscopically identified in cells infected with intact VZV. These sacs curved around, and ultimately enclosed, nucleocapsids. Tegument coated the concave face of these sacs, which formed the viral envelope, but the convex surface was tegument-free. TGN cisternae of cells infected with VZV mutants lacking gI (gI(Delta)) or its C (gI(DeltaC))- or N-terminal (gI(DeltaN))-terminal domains were uniformly tegument coated and adhered to one another, forming bizarre membranous stacks. Viral envelopment was compromised, and no virions were delivered to post-Golgi structures. The TGN was not gI-immunoreactive in cells infected with the gI(Delta) or gI(DeltaN) mutants, but it was in cells infected with gI(DeltaC) (because the ectodomains of gI and gE interact). The presence in the TGN of gI lacking a C-terminal domain, therefore, was not sufficient to maintain enveloping cisternae. In cells infected with intact VZV or with gI(Delta), gI(DeltaN), or gI(DeltaC) mutants, ORF10p immunoreactivity was concentrated on the cytosolic face of TGN membranes, suggesting that it interacts with the cytosolic domains of glycoproteins. Because of the gE-gI interaction, cotransfected cells that expressed gE or gI were able to target truncated forms of the other to the TGN. Our data suggest that the C-terminal domain of gI is required to segregate viral and cellular proteins in enveloping TGN cisternae.
View details for Web of Science ID 000165863000036
View details for PubMedID 11119602
View details for PubMedCentralID PMC113926
-
Immune evasion mechanisms of varicella-zoster virus
International Conference on Immunity and Prevention of Herpes Zoster
SPRINGER-VERLAG WIEN. 2001: 99–107
Abstract
Varicella-zoster virus can to modulate the expression of class I and class II major histocompatibility (MHC) molecules. MHC class I expression is downregulated in VZV-infected T cells as well as in fibroblasts. VZV-infected cells do not respond to exposure to interferon-gamma (IFN-gamma) by upregulation of MHC class II expression. However, MHC class II expression is induced when cells are treated with IFN-gamma before VZV infection. These effects on MHC class I and class II expression can be expected to interfere transiently with adaptive immune responses of the host, mediated by CD4 and CD8 T cells, ensuring that the virus has sufficient opportunity for transmission to susceptible contracts.
View details for Web of Science ID 000169113800011
View details for PubMedID 11339556
-
Glycoprotein e of varicella-zoster virus enhances cell-cell contact in polarized epithelial cells
JOURNAL OF VIROLOGY
2000; 74 (23): 11377-11387
Abstract
Varicella-zoster virus (VZV) infection involves the cell-cell spread of virions, but how viral proteins interact with the host cell membranes that comprise intercellular junctions is not known. Madin-Darby canine kidney (MDCK) cells were constructed to express the glycoproteins gE, gI, or gE/gI constitutively and were used to examine the effects of these VZV glycoproteins in polarized epithelial cells. At low cell density, VZV gE induced partial tight junction (TJ) formation under low-calcium conditions, whether expressed alone or with gI. Although most VZV gE was intracellular, gE was also shown to colocalize with the TJ protein ZO-1 with or without concomitant expression of gI. Freeze fracture electron microscopy revealed normal TJ strand morphology in gE-expressing MDCK cells. Functionally, the expression of gE was associated with a marked acceleration in the establishment of maximum transepithelial electrical resistance (TER) in MDCK-gE cells; MDCK-gI and MDCK-gE/gI cells exhibited a similar pattern of early TER compared to MDCK cells, although peak resistances were lower than those of gE alone. VZV gE expression altered F-actin organization and lipid distribution, but coexpression of gI modulated these effects. Two regions of the gE ectodomain, amino acids (aa) 278 to 355 and aa 467 to 498, although lacking Ca(2+) binding motifs, exhibit similarities with corresponding regions of the cell adhesion molecules, E-cadherin and desmocollin. These observations suggest that VZV gE and gE/gI may contribute to viral pathogenesis by facilitating epithelial cell-cell contacts.
View details for Web of Science ID 000170365800059
View details for PubMedID 11070038
View details for PubMedCentralID PMC113243
-
Varicella-zoster virus gE escape mutant VZV-MSP exhibits an accelerated cell-to-cell spread phenotype in both infected cell cultures and SCID-hu mice
VIROLOGY
2000; 275 (2): 306-317
Abstract
Varicella-zoster virus is considered to have one of the most stable genomes of all human herpesviruses. In 1998, we reported the unanticipated discovery of a wild-type virus that had lost an immunodominant B-cell epitope on the gE ectodomain (VZV-MSP); the gE escape mutant virus exhibited an unusual pattern of egress. Further studies have now documented a markedly enhanced cell-to-cell spread by the mutant virus in cell culture. This property was investigated by laser scanning confocal microscopy combined with a software program that allows the measurement of pixel intensity of the fluorescent signal. For this new application of imaging technology, the VZV immediate early protein 62 (IE 62) was selected as the fluoresceinated marker. By 48 h postinfection, the number of IE 62-positive pixels in the VZV-MSP-infected culture was nearly fourfold greater than the number of pixels in a culture infected with a low-passage laboratory strain. Titrations by infectious center assays supported the above image analysis data. Confirmatory studies in the SCID-hu mouse documented that VZV-MSP spread more rapidly than other VZV strains in human fetal skin implants. Generally, the cytopathology and vesicle formation produced by other strains at 21 days postinfection were demonstrable with VZV-MSP at 14 days. To assess whether additional genes were contributing to the unusual VZV-MSP phenotype, approximately 20 kb of the VZV-MSP genome was sequenced, including ORFs 31 (gB), 37 (gH), 47, 60 (gL), 61, 62 (IE 62), 66, 67 (gI), and 68 (gE). Except for a few polymorphisms, as well as the previously discovered mutation within gE, the nucleotide sequences within most open reading frames were identical to the prototype VZV-Dumas strain. In short, VZV-MSP represents a novel variant virus with a distinguishable phenotype demonstrable in both infected cell cultures and SCID-hu mice.
View details for Web of Science ID 000089697900012
View details for PubMedID 10998331
-
Measles vaccines - A positive step toward eradicating a negative strand
NATURE MEDICINE
2000; 6 (7): 744-745
View details for Web of Science ID 000088040100026
View details for PubMedID 10888917
-
Developmental maturation of the immune response to measles and mumps live viral vaccines.
OXFORD UNIV PRESS INC. 2000: 223–23
View details for Web of Science ID 000088950900107
-
Varicella-zoster virus infection of a human CD4-positive T-cell line
VIROLOGY
2000; 270 (2): 278-285
Abstract
Varicella-zoster virus (VZV) is a human alpha-herpesvirus that causes varicella (chickenpox) at primary infection and may reactivate as herpes zoster. VZV is a T-lymphotropic virus in vivo. To investigate the T-cell tropism of VZV, we constructed a recombinant virus expressing green fluorescent protein (VZV-GFP) under the CMV IE promoter. Coculture of VZV-GFP-infected fibroblasts with II-23 cells, a CD4-positive human T-cell hybridoma, resulted in transfer of virus to II-23 cells. II-23 cells are susceptible to VZV-GFP infection as demonstrated by expression of immediate/early (IE62), early (ORF4), and late (gE) genes. Recovery of infectious virus was limited, with only 1 to 3 in 10(6) cells releasing infectious virus by plaque assay, indicating that transfer of virus results in a limited productive infection. In vitro infection of II-23 cells will be useful for further analysis of VZV tropism for T-lymphocytes.
View details for Web of Science ID 000087227100005
View details for PubMedID 10792986
-
Frequencies of memory T cells specific for varicella-zoster virus, herpes simplex virus, and cytomegalovirus by intracellular detection of cytokine expression
39th Interdisciplinary Conference on Antimicrobial Agents and Chemotherapy (ICAAC)
OXFORD UNIV PRESS INC. 2000: 859–66
Abstract
Memory T cells specific for varicella-zoster virus (VZV), herpes simplex virus (HSV), and human cytomegalovirus (HCMV) were compared in immune adults by intracellular cytokine (ICC) detection. The mean percentages of CD4+ T cells were 0.11% for VZV and 0.22% for HSV by interferon (IFN)-gamma production; the frequency for HCMV was significantly higher at 1.21%. Percentages of VZV-, HSV-, and HCMV-specific CD4+ T cells were similar by use of tumor necrosis factor (TNF)-alpha. HCMV-stimulated CD8+ T cells produced IFN-gamma (1.11%) and TNF-alpha (1.71%); VZV- and HSV-specific CD8+ T cells were not detectable. VZV CD4+ T cell numbers were similar in young adults with natural or vaccine-induced immunity. VZV CD4+ T cells were significantly less frequent in older adults. Secondary varicella immunization did not increase VZV-specific CD4+ T cell frequencies by ICC assay. Numbers of memory T cells specific for herpesviruses may vary with sites of viral latency and with host age.
View details for Web of Science ID 000086344400007
View details for PubMedID 10720505
-
Modulation of major histocompatibility class II protein expression by varicella-zoster virus
JOURNAL OF VIROLOGY
2000; 74 (4): 1900-1907
Abstract
We sought to investigate the effects of varicella-zoster virus (VZV) infection on gamma interferon (IFN-gamma)-stimulated expression of cell surface major histocompatibility complex (MHC) class II molecules on human fibroblasts. IFN-gamma treatment induced cell surface MHC class II expression on 60 to 86% of uninfected cells, compared to 20 to 30% of cells which had been infected with VZV prior to the addition of IFN-gamma. In contrast, cells that were treated with IFN-gamma before VZV infection had profiles of MHC class II expression similar to those of uninfected cell populations. Neither IFN-gamma treatment nor VZV infection affected the expression of transferrin receptor (CD71). In situ and Northern blot hybridization of MHC II (MHC class II DR-alpha) RNA expression in response to IFN-gamma stimulation revealed that MHC class II DR-alpha mRNA accumulated in uninfected cells but not in cells infected with VZV. When skin biopsies of varicella lesions were analyzed by in situ hybridization, MHC class II transcripts were detected in areas around lesions but not in cells that were infected with VZV. VZV infection inhibited the expression of Stat 1alpha and Jak2 proteins but had little effect on Jak1. Analysis of regulatory events in the IFN-gamma signaling pathway showed that VZV infection inhibited transcription of interferon regulatory factor 1 and the MHC class II transactivator. This is the first report that VZV encodes an immunomodulatory function which directly interferes with the IFN-gamma signal transduction via the Jak/Stat pathway and enables the virus to inhibit IFN-gamma induction of cell surface MHC class II expression. This inhibition of MHC class II expression on VZV-infected cells in vivo may transiently protect cells from CD4(+) T-cell immune surveillance, facilitating local virus replication and transmission during the first few days of cutaneous lesion formation.
View details for Web of Science ID 000084958000036
View details for PubMedID 10644363
-
Genotypic stability of cold-adapted influenza virus vaccine in an efficacy clinical trial
JOURNAL OF CLINICAL MICROBIOLOGY
2000; 38 (2): 839-845
Abstract
An investigational live influenza virus vaccine, FluMist, contains three cold-adapted H1N1, H3N2, and B influenza viruses. The vaccine viruses are 6/2 reassortants, in which the hemagglutinin (HA) and neuraminidase (NA) genes are derived from the circulating wild-type viruses and the remaining six genes are derived from the cold-adapted master donor strains. The six genes from the cold-adapted master donor strains ensure the attenuation, and the HA and NA genes from the wild-type viruses confer the ability to induce protective immunity against contemporary influenza strains. The genotypic stability of this vaccine was studied by employing clinical samples collected during an efficacy trial. Viruses present in the nasal and throat swab specimens and in supernatants after culturing the specimens were detected and subtyped by multiplex reverse transcriptase (RT)-PCR. Complete genotypes of these detected viruses were determined by a combination of RT-PCR and restriction fragment length polymorphism, multiplex RT-PCR and fluorescent single-strand conformation polymorphism, and nucleic acid sequencing analysis. The FluMist vaccine appeared to be genotypically stable after replication in the human host. All viruses detected during the 2-week postvaccination period were shed vaccine viruses and had maintained the 6/2 genotype.
View details for Web of Science ID 000085187200064
View details for PubMedID 10655394
View details for PubMedCentralID PMC86217
-
Varicella-zoster virus: Pathogenesis, immunity, and clinical management in hematopoietic cell transplant recipients
BIOLOGY OF BLOOD AND MARROW TRANSPLANTATION
2000; 6 (3): 219-230
Abstract
New information about the mechanisms of varicella-zoster virus (VZV) pathogenesis and the host response to the virus has improved our understanding of the threat that VZV reactivation may pose after hematopoietic cell transplantation (HCT). Antiviral therapy compensates for some of the deficiencies in VZV immunity in HCT recipients, and inactivated varicella vaccine may be useful for the early reconstitution of adaptive immunity to VZV after HCT.
View details for Web of Science ID 000090022300002
View details for PubMedID 10871147
-
Intravenous ribavirin therapy for adenovirus pneumonia
PEDIATRIC PULMONOLOGY
2000; 29 (1): 69-73
Abstract
We report on the effectiveness of intravenous ribavirin for severe adenoviral pneumonia in a 10-month-old male following orthotopic liver transplantation. On day 20 post-transplantation, he developed high fever, marked respiratory compromise, and hypoxemia. The chest radiograph showed bilateral pulmonary infiltrates. Samples of bronchoalveolar lavage fluid grew adenovirus, serotype 1. Marked clinical and radiological improvement was noted after intravenous ribavirin therapy. A prospective clinical trial is needed to determine the efficacy of ribavirin therapy for severe adenovirus disease.
View details for Web of Science ID 000084587800011
View details for PubMedID 10613789
-
Analysis of immune responses to varicella tester viral proteins induced by DNA vaccination
ANTIVIRAL RESEARCH
1999; 44 (3): 179-192
Abstract
In this study we sought to examine the mechanism by which immune responses were induced following intramuscular injection of mice with DNA expression vectors encoding genes of varicella zoster virus (VZV). Both VZV-specific antibody and T cell proliferative responses were induced by immunization with DNA sequences for the immediate early 62 (IE62) and glycoprotein E (gE). The viral proteins were shown to be expressed in non-regenerating, rather than regenerating muscle cells. After primary immunization, muscle cells did not express major histocompatibility complex (MHC) class II transcripts and little inflammatory response was detected at the site of inoculation. Histochemical staining and non-isotopic in situ hybridization demonstrated that a second injection of IE62 plasmid DNA was again associated with protein synthesis in non-regenerating muscle cells but that a marked inflammatory infiltrate was induced in muscle tissue. These cells, but not muscle cells, expressed MHC class II transcripts. Significantly, PCR analyses demonstrated that IE62 DNA localized specifically to local draining lymph nodes following primary DNA immunization by intramuscular inoculation. These experiments indicate that transport of plasmid DNA to sites of antigen presentation in regional lymphoid tissue may play an important role in the initial generation of immune responses and that enhancement by secondary inoculation is mediated by immune cells that traffic to the site of viral protein synthesis in muscle cells.
View details for Web of Science ID 000084820600004
View details for PubMedID 10651069
-
Nocardia farcinica pneumonia in chronic granulomatous disease
PEDIATRICS
1999; 104 (4): 961-964
Abstract
Infection with Nocardia poses a diagnostic challenge in patients with chronic granulomatous disease (CGD) because the signs and symptoms are often nonspecific, delay in diagnosis is common, and invasive procedures are frequently required to obtain appropriate tissue specimens. We present the first reported case of N farcinica pneumonia in an adolescent with X-linked CGD. Differentiation of N farcinica from other members of N asteroides complex is important because of its propensity for causing disseminated infection and antimicrobial resistance. Physicians caring for patients with CGD should maintain a high index of suspicion for nocardiosis, especially in those receiving chronic steroid therapy. Early diagnosis remains critical for decreased morbidity and occasional mortality.
View details for Web of Science ID 000082907300031
View details for PubMedID 10506241
-
Lessons learned from a review of the development of selected vaccines
PEDIATRICS
1999; 104 (4): 942-950
View details for Web of Science ID 000082907300014
-
The epidemiology of neonatal herpes simplex virus infections in California from 1985 to 1995
Annual Meeting on the General Clinical Research Center
OXFORD UNIV PRESS INC. 1999: 199–202
Abstract
Comprehensive hospital discharge data completed by the California Office of Statewide Health Planning and Development was used to determine whether the proportion of infants =6 weeks of age who were hospitalized with a diagnosis of herpes simplex virus (HSV) infection changed between 1985 and 1995. During 1985, 1990, and 1995, respectively, 11.7, 11.3, and 11.4 infants per 100,000 live births had a diagnosis of HSV (P=.98). The proportion of infants 1-42 days of age who were discharged from the hospital with a diagnosis of HSV infection did not change over this time period despite a decrease in deliveries by cesarean section and an increase in the proportion of women with a diagnosis of genital HSV infection who gave birth to infants by vaginal delivery. From 1985 to 1995 there was no decrease in the rate of secondary diagnosis of genital HSV in delivering women.
View details for Web of Science ID 000081132100027
View details for PubMedID 10353880
-
IL-12, IFN-gamma, and T cell proliferation to measles in immunized infants
JOURNAL OF IMMUNOLOGY
1999; 162 (9): 5569-5575
Abstract
Measles infection in infants is associated with severe complications, and secondary infections are attributed to generalized immunosuppression. Measles binding to its monocyte receptor down-regulates IL-12 which is expected to diminish Th1-like cytokine responses, including IFN-gamma. Whether young infants can be immunized effectively against measles is an important public health issue. We evaluated Ag-specific IL-12, IFN-gamma, and T cell responses of infants at 6 (n = 60), 9 (n = 46), or 12 mo (n = 56) of age and 29 vaccinated adults. IL-12 and IFN-gamma release by PBMC stimulated with measles Ag increased significantly after measles immunization in infants. IL-12 and IFN-gamma concentrations were equivalent in younger and older infants, but IL-12 concentrations were significantly lower in infants than in adults (p = 0.04). IL-12 production by monocytes was down-regulated by measles; the addition of recombinant human IL-12 enhanced IFN-gamma production by PBMC stimulated with measles Ag, but infant T cells released significantly less IFN-gamma than adult T cells under this condition. Of particular interest, the presence of passive Abs to measles had no effect on the specific T cell proliferation or IFN-gamma production after measles stimulation. Cellular immunity to measles infection and vaccination may be limited in infants compared with adults as a result of less effective IFN-gamma and IL-12 production in response to measles Ags. These effects were not exaggerated in younger infants compared with effects in infants who were immunized at 12 mo. In summary, infant T cells were primed with measles Ag despite the presence of passive Abs, but their adaptive immune responses were limited compared with those of adults.
View details for Web of Science ID 000079892600073
View details for PubMedID 10228039
-
Characterization of varicella-zoster virus glycoprotein K (open reading frame 5) and its role in virus growth
JOURNAL OF VIROLOGY
1999; 73 (5): 4197-4207
Abstract
Varicella-zoster virus (VZV) is an alphaherpesvirus that is the causative agent of chickenpox and herpes zoster. VZV open reading frame 5 (ORF5) encodes glycoprotein K (gK), which is conserved among alphaherpesviruses. While VZV gK has not been characterized, and its role in viral replication is unknown, homologs of VZV gK in herpes simplex virus type 1 (HSV-1) and pseudorabies virus (PRV) have been well studied. To identify the VZV ORF5 gene product, we raised a polyclonal antibody against a fusion protein of ORF5 codons 25 to 122 with glutathione S-transferase and used it to study the protein in infected cells. A 40,000-molecular-weight protein was detected in cell-free virus by Western blotting. In immunogold electron microscopic studies, VZV gK was in enveloped virions and was evenly distributed in the cytoplasm in infected cells. To determine the function of VZV gK in virus growth, a series of gK deletion mutants were constructed with VZV cosmid DNA derived from the Oka strain. Full and partial deletions in gK prevented viral replication when the gK mutant cosmids were transfected into melanoma cells. Insertion of the HSV-1 (KOS) gK gene into the endogenous VZV gK site did not compensate for the deletion of VZV gK. The replacement of VZV gK at a nonnative AvrII site in the VZV genome restored the phenotypic characteristics of intact recombinant Oka (rOka) virus. Moreover, gK complementing cells transfected with a full gK deletion mutant exhibited viral plaques indistinguishable from those of rOka. Our results are consistent with the studies of gK proteins of HSV-1 and PRV showing that gK is indispensable for viral replication.
View details for Web of Science ID 000079701100078
View details for PubMedID 10196316
View details for PubMedCentralID PMC104199
-
Varicella-zoster virus immune evasion
IMMUNOLOGICAL REVIEWS
1999; 168: 143-156
Abstract
CD4+ and CD8+ T cells play dual roles in varicella-zoster virus (VZV) pathogenesis. The first role is to deliver the virus to cutaneous sites during primary VZV infection, permitting replication at these sites and the successful transmission of the virus to other susceptible individuals. The second contribution of T cells is to provide the critical antigen-specific adaptive immunity needed to stop viral replication and maintain VZV latency in sensory ganglia. The equilibrium between VZV and the host can be predicted to be served by immune evasion mechanisms in at least two important ways, including the facilitation of cell-associated viremia during primary VZV infection and silent persistence in dorsal root ganglia. Interference with antigen presentation by MHC class I downregulation may be expected to play a role in both circumstances. Transient interference with MHC class II expression in varicella skin lesions should facilitate local replication and transmission. In addition, when VZV reactivates, the capacity of viral gene products to block the upregulation of MHC class II expression triggered by interferon-gamma should permit a sufficient period of viral replication to cause the lesions of herpes zoster, despite the presence of VZV-specific T cells, and to allow transmission of the virus to susceptible individuals. Although the effort is at an early stage compared to studies of other viral pathogens, identifying the VZV gene products that exert these effects and their mechanisms of interference has the potential to reveal novel aspects of MHC class I and class II antigen processing and presentation.
View details for Web of Science ID 000081048100012
View details for PubMedID 10399071
-
Immune responses of 6, 9 and 12 month old infants immunized with measles or mumps vaccine and the effects of passive antibodies on these responses
NATURE PUBLISHING GROUP. 1999: 161A–161A
View details for Web of Science ID 000079476700940
-
Chickenpox (varicella).
Contributions to microbiology
1999; 3: 96-110
View details for PubMedID 10599524
-
Development of recombinant varicella-zoster virus vaccines.
Contributions to microbiology
1999; 3: 193-200
View details for PubMedID 10599531
-
Management of varicella-zoster virus infections in children
5th Triennial Symposium on New Directions in Antiviral Chemotherapy
KLUWER ACADEMIC/PLENUM PUBL. 1999: 167–174
Abstract
The introduction of varicella vaccine for immunization of healthy children is expected to have a gradual impact on the incidence of VZV infections in the population but antiviral therapy remains an important intervention in clinical practice. The efficacy of aciclovir for treatment of primary and recurrent VZV infections in children has reduced the morbidity and mortality of these illnesses in immunocompromised children dramatically. Oral aciclovir is an effective and useful for the management of varicella in healthy children and adolescents.
View details for Web of Science ID 000082968200016
View details for PubMedID 10549389
-
Comparison of primary sensitization of naive human T cells to varicella-zoster virus peptides by dendritic cells in vitro with responses elicited in vivo by varicella vaccination
3rd International Conference of the Varicella-Zoster Virus
AMER ASSOC IMMUNOLOGISTS. 1999: 560–67
Abstract
Dendritic cells (DC) are potent APC during primary and secondary immune responses. The first objective of this study was to determine whether human DC mediate in vitro sensitization of naive CD4+ T cells to epitopes of the immediate early 62 (IE62) protein of varicella zoster virus (VZV). The induction of CD4+ T cell proliferative responses to eight synthetic peptides representing amino acid sequences of the VZV IE62 protein was assessed using T cells and DC from VZV-susceptible donors. The second objective was to compare in vitro responses of naive T cells with responses to VZV peptides induced in vivo after immunization with varicella vaccine. T cell proliferation was induced by three peptides, P1, P4, and P7, in 71-100% of the donors tested before and after vaccination using DC as APC. Monocytes were effective APC for VZV peptides only after immunization. Two peptides, P2 and P8, induced naive T cell proliferation less effectively and were also less immunogenic for T cells from vaccinated or naturally immune donors. T cell recognition of specific peptides was concordant between naive, DC-mediated responses, and postvaccine responses using monocytes as APC in 69% of comparisons (p = 0.05; chi2); the predictive value of a positive response to an IE62 peptide before immunization for T cell sensitization in vivo was 82%. These observations indicate that primary T cell responses detected in vitro using DC as APC may be useful to characterize the potential immunogenicity of viral protein epitopes in vivo.
View details for Web of Science ID 000077748100072
View details for PubMedID 9886433
-
Analysis of the glycoproteins I and E of varicella-zoster virus (VZV) using deletional mutations of VZV cosmids
3rd International Conference of the Varicella-Zoster Virus
UNIV CHICAGO PRESS. 1998: S22–S26
Abstract
The contributions of the glycoproteins gI (ORF67) and gE (ORF68) to varicella-zoster virus (VZV) replication were investigated in deletion mutants made by using cosmids with VZV DNA derived from the Oka strain. These experiments demonstrated that gI was not required for VZV replication in vitro but gE appeared to be. Although VZV gI was not required, its deletion or mutation resulted in a significant decrease in infectious virus yields, and it disrupted syncytial formation and altered the conformation and distribution of gE in infected cells. Normal cell-to-cell spread and replication kinetics were restored when gI was expressed from a non-native locus in the VZV genome. The expression of intact gI, the ORF67 gene product, is required for efficient VZV replication.
View details for Web of Science ID 000077034100006
View details for PubMedID 9852968
-
Polymerase chain reaction and restriction fragment length polymorphism analysis of varicella-zoster virus isolates from the United States and other parts of the world
3rd International Conference of the Varicella-Zoster Virus
UNIV CHICAGO PRESS. 1998: S64–S66
Abstract
A polymerase chain reaction (PCR) assay that identifies and differentiates wild-type (wt) and vaccine strains of varicella-zoster virus (VZV) was used to determine if VZV strains with restriction fragment length polymorphisms resembling those of the Japanese Oka vaccine strain were present in the wt pool outside of Japan. Virus samples (n = 114) from patients with chickenpox and zoster from various parts of the United States and Australia were analyzed. The assay correctly identified 113 samples as wt strain. The 1 sample identified as Oka vaccine strain came from a child with leukemia who developed a vaccine-associated rash after receiving the live attenuated varicella vaccine. At this point, there is no evidence that wt strains resembling the vaccine are circulating outside of Japan. This indicates that this PCR assay can be utilized to distinguish rashes due to vaccine and wt VZV.
View details for Web of Science ID 000077034100015
View details for PubMedID 9852977
-
Varicella-zoster virus IE63, a virion component expressed during latency and acute infection, elicits humoral and cellular immunity
3rd International Conference of the Varicella-Zoster Virus
UNIV CHICAGO PRESS. 1998: S43–S47
Abstract
Varicella-zoster virus (VZV) latency in human dorsal root ganglia is characterized by the transcription of large regions of its genome and by the expression of large amounts of some polypeptides, which are also expressed during lytic cycles. The immediate early 63 protein (IE63) is a virion component expressed very early in cutaneous lesions and the first viral protein detected during latency. Immune response against IE63 has been evaluated among naturally immune adults with a history of chickenpox: Specific antibodies were detected in serum, and most subjects who had a T cell proliferation with unfractionated VZV antigens had T cell recognition of purified IE63. The cytotoxic T cell (CTL) response to IE63 was equivalent to CTL recognition of IE62, the major tegument component of VZV, whose immunogenicity has been previously described. T cell recognition of IE63 and other VZV proteins is one of the likely mechanisms involved in controlling VZV reactivation from latency.
View details for Web of Science ID 000077034100010
View details for PubMedID 9852972
-
Isolation and utilization of human dendritic cells from peripheral blood to assay an in vitro primary immune response to varicella-zoster virus peptides
3rd International Conference of the Varicella-Zoster Virus
UNIV CHICAGO PRESS. 1998: S39–S42
Abstract
A human dendritic cell-based assay used to monitor a T cell proliferation response to viral peptides in vitro is described. Dendritic cells and autologous CD4+ T cells were isolated from peripheral blood by a series of density-gradient centrifugations or magnetic bead separations (or both). Peptides corresponding to residues of the immediate early protein, IE62, of varicella-zoster virus (VZV) were used as stimulating antigens, and persons with no history of varicella and no humoral or cellular immunity to VZV served as naive donors for the assays. Three VZV-susceptible donors were tested, and all demonstrated an in vitro response to multiple VZV peptides. This assay has potential as a screen to establish the immunogenicity of viral antigens in vitro using T cells from naive donors.
View details for Web of Science ID 000077034100009
View details for PubMedID 9852971
-
Interleukin (IL)-10, IL-12, and interferon-gamma production in primary and memory immune responses to varicella-zoster virus
JOURNAL OF INFECTIOUS DISEASES
1998; 178 (4): 940-948
Abstract
Varicella immunization provided the opportunity to examine the kinetics of interleukin (IL)-10, IL-12 and interferon (IFN)-gamma production elicited during primary in vivo sensitization with proteins of varicella-zoster virus (VZV), a common human herpesvirus. VZV-specific IFN-gamma release and T cell proliferation were elicited by immunization and persisted through 15 months of follow-up. The induction of VZV-specific T cells and IgG antibodies was accompanied by transient increases in IL-10 and IL-12 production. T cell proliferation to VZV was significantly lower in adults at 15 months than in vaccinated children or naturally immune subjects and correlated with lower IFN-gamma responses in individual vaccinees. After primary immunity was induced, continued IL-12 production was not necessary to maintain the predominant Th1-type response elicited by VZV. Cytokine profiles observed during primary in vivo sensitization to VZV suggest that parallel increases in IFN-gamma and IL-10 may be important in the induction of immunity to some viral pathogens.
View details for Web of Science ID 000076248000003
View details for PubMedID 9806019
-
The ORF47 and ORF66 putative protein kinases of varicella-zoster virus determine tropism for human T cells and skin in the SCID-hu mouse
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
1998; 95 (20): 11969-11974
Abstract
The varicella-zoster virus (VZV) genes ORF47 and ORF66 are predicted to encode serine/threonine protein kinases, which are homologs of herpes simplex virus 1 (HSV-1) UL13, and US3. When mutants were constructed by inserting stop codons into ORF47 and ORF66, the recombinants ROka47S and ROka66S, as well as intact ROka replicated in tissue culture. In contrast, inoculation of human thymus/liver or skin implants in SCID-hu mice showed that ORF47 protein was required for viral growth in human T cells and skin. Eliminating ORF66 expression inhibited VZV infectivity for T cells partially but did not impair replication in skin compared with ROka. Infectivity for T cells and skin was restored when ROka47S virus was complemented by insertion of ORF47 into a distant, noncoding site. The ORF47 gene product is the first VZV protein identified as necessary for T cell tropism. It also is essential for skin infectivity in vivo, as is glycoprotein C. Expression of ORF66 did not compensate for the absence of the ORF47 protein. The requirement for ORF47 expression in T cells and skin indicates that this gene product, which is dispensable in vitro, has a critical role within differentiated cells that are essential targets for VZV pathogenesis in vivo.
View details for Web of Science ID 000076222200083
View details for PubMedID 9751774
View details for PubMedCentralID PMC21749
-
Deficiency of the humoral immune response to measles vaccine in infants immunized at age 6 months
JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION
1998; 280 (6): 527-532
Abstract
Measles causes serious morbidity in infants, with the highest risk among those who are 6 to 12 months of age. In the United States, measles vaccine has been given at age 12 to 15 months to minimize interference by passive antibodies and to achieve the high seroprevalence required for herd immunity. Infants of mothers with vaccine-induced immunity may lose passively acquired antibodies before 12 months, leaving them susceptible to measles infection.To assess the immunogenicity of measles vaccine in infants younger than 12 months.Cohort study conducted before and after measles immunization.Pediatric clinic in Palo Alto, Calif.Infants 6 (n = 27), 9 (n = 26), and 12 (n = 34) months of age were enrolled; 72 provided both initial and follow-up samples.Evaluation of immunogenicity before and 12 weeks after measles vaccination, including measles neutralizing antibody titers, measles-specific T-cell proliferation, and cytokine profiles.Measles neutralizing antibodies were present before vaccination in 52% (12/23), 35% (7/20), and 0% (0/22) of 6-, 9-, and 12-month-old infants, respectively. In the absence of detectable passive antibodies, geometric mean titers after vaccination were significantly lower in 6-month-old infants compared with 9-month-old infants (27 vs 578, P = .01) and 12-month-old infants (27 vs 972, P=.001). The seroconversion rate, defined as a 4-fold rise in antibody titer, in these 6-month-old infants was only 67%, and only 36% of these infants achieved seroprotective neutralizing antibody titers of 120 or higher after vaccination compared with 100% of 9- and 12-month-old infants lacking detectable passive antibody prior to vaccination. T-cell proliferation and cytokine responses to measles did not differ with age.Humoral immunity was deficient in 6-month-old infants given measles vaccine, even in the absence of detectable passively acquired neutralizing antibodies. Comparison of their responses with those of 9- and 12-month-old infants indicates that a developmental maturation of the immune response to measles may occur during the first year of life, which affects the immunogenicity of measles vaccine.
View details for Web of Science ID 000075244900028
View details for PubMedID 9707142
-
Analysis of the persistence of humoral and cellular immunity in children and adults immunized with varicella vaccine
Western-Society-for-Pediatric-Research Meeting
UNIV CHICAGO PRESS. 1998: 1701–4
Abstract
The persistence of humoral and cellular immunity to varicella-zoster virus (VZV) was evaluated in 60 children and 18 adults immunized with live attenuated VZV vaccine. At a mean of 5 years after vaccination, 93% of children and 94% of adults had IgG antibodies to VZV as determined by ELISA. VZV antibody concentrations were significantly higher at 5 years than at 1 year after immunization in children and adults. Cell-mediated immunity to VZV was detected in 87% of children and 94% of adults at 5 years. The mean stimulation index was significantly higher at 5 years than at 1 year among children and adults. Cytokine responses to VZV, including interleukin-2, interferon-gamma, and interleukin-10 were equivalent between children and adults at 5 years. In summary, varicella immunization induced long-term humoral and cellular immunity, and initial differences between cell-mediated responses in children and adults diminished over time.
View details for Web of Science ID 000073771500035
View details for PubMedID 9607852
-
Attenuation of the vaccine Oka strain of varicella-zoster virus and role of glycoprotein C in alphaherpesvirus virulence demonstrated in the SCID-hu mouse
JOURNAL OF VIROLOGY
1998; 72 (2): 965-974
Abstract
The SCID-hu mouse implanted with human fetal tissue is a novel model for investigating human viral pathogenesis. Infection of human skin implants was used to investigate the basis for the clinical attenuation of the varicella-zoster virus (VZV) strain, V-Oka, from which the newly licensed vaccine is made. The pathogenicity of V-Oka was compared with that of its parent, P-Oka, another low-passage clinical isolate, strain Schenke (VZV-S), and VZV-Ellen, a standard laboratory strain. The role of glycoprotein C (gC) in infectivity for human skin was assessed by using gC-negative mutants of V-Oka and VZV-Ellen. Whereas all of these VZV strains replicated well in tissue culture, only low-passage clinical isolates were fully virulent in skin, as shown by infectious virus yields and analysis of implant tissues for VZV DNA and viral protein synthesis. The infectivity of V-Oka in skin was impaired compared to that of P-Oka, providing the first evidence of a virologic basis for the clinical attenuation of V-Oka. The infectivity of V-Oka was further diminished in the absence of gC expression. All strains except gC-Ellen retained some capacity to replicate in human skin, but cell-free virus was recovered only from implants infected with P-Oka or VZV-S. Although VZV is closely related to herpes simplex virus type 1 (HSV-1) genetically, experiments in the SCID-hu model revealed differences in tropism for human cells that correlated with differences in VZV and HSV-1 disease. VZV caused extensive infection of epidermal and dermal skin cells, while HSV-1 produced small, superficial lesions restricted to the epidermis. As in VZV, gC expression was a determinant for viral replication in skin. VZV infects human CD4+ and CD8+ T cells in thymus/liver implants, but HSV-1 was detected only in epithelial cells, with no evidence of lymphotropism. These SCID-hu mouse experiments show that the clinical attenuation of the varicella vaccine can be attributed to decreased replication of V-Oka in skin and that tissue culture passage alone reduces the ability of VZV to infect human skin in vivo. Furthermore, gC, which is dispensable for replication in tissue culture, plays a critical role in the virulence of the human alphaherpesviruses VZV and HSV-1 for human skin.
View details for Web of Science ID 000071440200010
View details for PubMedID 9444989
View details for PubMedCentralID PMC124567
-
Reliability of a history of previous varicella infection in adults
26th Interscience Conference on Antimicrobial Agents and Chemotherapy
AMER MEDICAL ASSOC. 1997: 1520–22
Abstract
Apparent second episodes of varicella are reported in immunocompetent hosts, but laboratory confirmation of prior immune status has rarely been possible.To evaluate adult patients with varicella who claimed to have had previous varicella to determine whether they had true second episodes or primary cases with inaccurate clinical histories.Adult subjects with varicella who enrolled in an antiviral treatment trial were interviewed about a history of varicella. The clinical course of varicella was documented prospectively in all subjects. Serum samples that predated the acute illness were obtained from the US Navy's central serum storage facility for subjects who reported a previous episode of varicella. These stored samples were tested in parallel by enzyme-linked immunosorbent assay, latex agglutination, and Western blot for IgG antibodies to varicella-zoster virus (VZV).Twenty military personnel with varicella and a history of the disease.A military hospital in San Diego, Calif.Presence or absence of antibodies to VZV.Twenty (10.8%) of 184 adults with serologically confirmed acute varicella reported a prior history of varicella. The clinical course of these 20 patients did not differ from those with no history of varicella. Serum samples that had been collected a mean of 12.4 months (median, 12 months; range, 3 days to 34 months) before the incident episode were available for 19 subjects. All 19 serum samples lacked IgG antibodies to VZV.A history of previous varicella infection in adults with varicella may not be reliable. True second episodes of varicella are probably rare in immunocompetent adults.
View details for Web of Science ID A1997YE44500037
View details for PubMedID 9363973
-
Mutational analysis of the role of glycoprotein I in Varicella-Zoster virus replication and its effects on glycoprotein E conformation and tracking
JOURNAL OF VIROLOGY
1997; 71 (11): 8279-8288
Abstract
The contributions of the glycoproteins gI (ORF67) and gE (ORF68) to varicella-zoster virus (VZV) replication were investigated in deletion mutants made by using cosmids with VZV DNA derived from the Oka strain. Deletion of both gI and gE prevented virus replication. Complete deletion of gI or deletions of 60% of the N terminus or 40% of the C terminus of gI resulted in a small plaque phenotype as well as reduced yields of infectious virus. Melanoma cells infected with gI deletion mutants formed abnormal polykaryocytes with a disrupted organization of nuclei. In the absence of intact gI, gE became localized in patches on the cell membrane, as demonstrated by confocal microscopy. A truncated N-terminal form of gI was transported to the cell surface, but its expression did not restore plaque morphology or infectivity. The fusogenic function of gH did not compensate for gI deletion or the associated disruption of the gE-gI complex. These experiments demonstrated that gI was dispensable for VZV replication in vitro, whereas gE appeared to be required. Although VZV gI was dispensable, its deletion or mutation resulted in a significant decrease in infectious virus yields, disrupted syncytium formation, and altered the conformation and distribution of gE in infected cells. Normal cell-to-cell spread and replication kinetics were restored when gI was expressed from a nonnative locus in the VZV genome. The expression of intact gI, the ORF67 gene product, is required for efficient membrane fusion during VZV replication.
View details for Web of Science ID A1997YB14300024
View details for PubMedID 9343180
View details for PubMedCentralID PMC192286
-
Herpes simplex virus type 2 - A persistent problem
NEW ENGLAND JOURNAL OF MEDICINE
1997; 337 (16): 1158-1159
View details for Web of Science ID A1997YA91200009
View details for PubMedID 9329938
-
Recognition of the latency-associated immediate early protein IE63 of varicella-zoster virus by human memory T lymphocytes
JOURNAL OF IMMUNOLOGY
1997; 159 (6): 2802-2806
Abstract
Varicella-zoster virus (VZV) is a human alpha herpesvirus that establishes latency in sensory ganglia. Latency is characterized by the abundant expression of the immediate early protein 63 (IE63), whereas other viral proteins have not yet been detected during the quiescent phase of VZV infection. The IE63 protein is a component of the virion and is expressed very early in the infectious cycle. The IE63 protein is also expressed in skin during episodes of varicella and herpes zoster. We have evaluated the cell-mediated immune response against IE63 in naturally immune adults with a history of chickenpox, by T lymphoproliferation and cytotoxicity assays. Among donors who had T cell proliferation to unfractionated VZV Ags from infected cell extract, 59% had T cell recognition of purified IE63. The CTL response to IE63 was equivalent to CTL recognition of IE62, the major tegument component of VZV whose immunogenicity has been previously described. IgG Abs against IE63 were detected in serum from healthy immune adults. These results indicate that IE63 is an important target of immunity to VZV. T cell recognition of IE63 is likely to be involved in controlling VZV reactivation from latency.
View details for Web of Science ID A1997XV75000033
View details for PubMedID 9300702
-
Early reconstitution of immunity and decreased severity of herpes zoster in bone marrow transplant recipients immunized with inactivated varicella vaccine
Antibody Workshop - The Role of Humoral Immunity in the Treatment and Prevention of Emerging and Extant Infectious Diseases
OXFORD UNIV PRESS INC. 1997: 578–85
Abstract
Varicella-zoster virus (VZV) causes herpes zoster after bone marrow transplantation (BMT). The immunogenicity of heat-inactivated varicella vaccine and effects on VZV pathogenesis were evaluated in 75 BMT patients randomized to receive vaccine or no intervention. Among 14 patients given a single dose at 1 month after transplantation, the mean (+/-SE) stimulation index (SI) was 12.20 +/- 3.13 compared with 4.83 +/- 2.74 (P = .036) in 14 unvaccinated patients, but clinical disease was not altered. Among 24 patients vaccinated at 1, 2, and 3 months, mean SI was 8.43 +/- 3.89 versus 2.00 +/- 0.33 (P = .014) in 23 unvaccinated patients at 4 months and 8.56 +/- 2.81 versus 5.30 +/- 2.47 (P = .043) at 5 months. Disease severity associated with VZV reactivation was decreased dramatically in vaccinees given three doses; severity scores were 6.4 +/- 1.0 versus 11.8 +/- 1.1 (P = .007). This experience with varicella vaccine in BMT patients is the first evidence that active immunization can reduce morbidity due to herpesvirus reactivation in high-risk populations.
View details for PubMedID 9291302
-
Live attenuated varicella vaccine
PEDIATRIC ANNALS
1997; 26 (6): 384-388
View details for Web of Science ID A1997XE14800007
View details for PubMedID 9188131
-
Measles, mumps, rubella, and varicella combination vaccine: Safety and immunogenicity alone and in combination with other vaccines given to children
CLINICAL INFECTIOUS DISEASES
1997; 24 (5): 925-931
Abstract
Eight hundred and twelve children, 12 months to 3.5 years of age, were enrolled in two clinical studies to evaluate the safety and immunogenicity of a live, attenuated combination vaccine for measles, mumps, rubella, and varicella (MMRV). Children were enrolled in one of two randomized, multicenter studies, involving administration of (1) MMRV and placebo vs. measles, mumps, and rubella vaccine (M-M-R(II)) and varicella-zoster virus vaccine (VARIVAX), given at separate anatomic sites at the same office visit; or (2) MMRV, DTaP (diphtheria, tetanus, and acellular pertussis vaccine) and OPV (oral polio vaccine) vs. M-M-R(II), DTaP, and OPV, with VARIVAX given 6 weeks later. All vaccine regimens were generally well tolerated. More than 95% of vaccinees seroconverted for measles, mumps, rubella, and varicella, regardless of the vaccine or regimen used. In each study, the level of antibody titer to varicella virus was significantly lower in vaccinees receiving MMRV than in those who received VARIVAX in a separate syringe.
View details for Web of Science ID A1997WX25700029
-
The synthesis and immunogenicity of varicella-zoster virus glycoprotein E and immediate-early protein (IE62) expressed in recombinant herpes simplex virus-1
ANTIVIRAL RESEARCH
1997; 33 (3): 187-200
Abstract
In order to evaluate the conditions for optimal expression and immunogenicity of varicella-zoster virus (VZV) proteins in a herpes simplex virus-1 (HSV-1) vector, we selected the VZV glycoprotein E (gE), encoded by ORF 68 and the VZV product of ORF 62, an immediate-early major tegument protein (IE62). Three HSV/VZV recombinants were generated: (1) VZV gE protein coding sequences along with the promoter region were inserted into the thymidine kinase (TK) gene of HSV-1 strain KOS; (2) VZV gE expressed from the HSV-1 ICP4 promoter was inserted into the glycoprotein C (gC) gene of HSV-1 strain F; and (3) VZV IE62 protein coding sequences under the control of the HSV-1 ICP4 promoter were inserted into the gC gene of HSV-1 strain F. Immunoblot analysis and immunoperoxidase staining of infected cell monolayers demonstrated vector expression of VZV proteins. Following intracranial inoculation in mice, both VZV gE-HSV (TK) and VZV IE62-HSV (gC) induced an IgG response against VZV gE or VZV IE62. When tested in cytotoxicity assays using T-lymphocytes from VZV immune human donors, the range of precursor frequencies for T-lymphocytes that recognized VZV gE or VZV IE62 was similar whether these proteins were expressed by HSV-1 or a vaccinia vector. These experiments demonstrate that HSV-1 is a competent vector for expression of these VZV proteins and support the feasibility of engineering a combined vaccine for these closely related alpha-herpesviruses.
View details for Web of Science ID A1997WH07400005
View details for PubMedID 9037375
-
The varicella vaccine.
Current clinical topics in infectious diseases
1997; 17: 110-146
View details for PubMedID 9189664
-
Application of the polymerase chain reaction to the diagnosis and management of neonatal herpes simplex virus disease. National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group.
journal of infectious diseases
1996; 174 (6): 1162-1167
Abstract
Cerebrospinal fluid (CSF) specimens from 77 neonates with herpes simplex virus (HSV) disease were evaluated retrospectively by polymerase chain reaction (PCR). Samples were collected from 202 infants enrolled in a National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group trial that compared vidarabine with acyclovir for the treatment of neonatal HSV infection. HSV DNA was detected in the CSF of 26 (76%) of 34 infants with CNS disease, in 13 (93%) of 14 infants with disseminated infection, and in 7 (24%) of 29 with skin, eye, or mouth (SEM) involvement. One of the 7 PCR-positive SEM patients subsequently developed severe neurologic impairment. Eighteen (95%) of 19 infants with positive CSF PCR results after the completion of 10 days of antiviral therapy experienced significant morbidity or mortality. Application of PCR to neonatal HSV disease may provide additional information on which clinical decisions may be based, although its diagnostic utility outside the research setting is unproven.
View details for PubMedID 8940204
-
Application of the polymerase chain reaction to the diagnosis and management of neonatal herpes simplex virus disease
35th Interscience Conference on Antimicrobial Agents and Chemotherapy
OXFORD UNIV PRESS INC. 1996: 1162–67
Abstract
Cerebrospinal fluid (CSF) specimens from 77 neonates with herpes simplex virus (HSV) disease were evaluated retrospectively by polymerase chain reaction (PCR). Samples were collected from 202 infants enrolled in a National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group trial that compared vidarabine with acyclovir for the treatment of neonatal HSV infection. HSV DNA was detected in the CSF of 26 (76%) of 34 infants with CNS disease, in 13 (93%) of 14 infants with disseminated infection, and in 7 (24%) of 29 with skin, eye, or mouth (SEM) involvement. One of the 7 PCR-positive SEM patients subsequently developed severe neurologic impairment. Eighteen (95%) of 19 infants with positive CSF PCR results after the completion of 10 days of antiviral therapy experienced significant morbidity or mortality. Application of PCR to neonatal HSV disease may provide additional information on which clinical decisions may be based, although its diagnostic utility outside the research setting is unproven.
View details for Web of Science ID A1996VV27200003
-
T cell recognition and cytokine production elicited by common and type-specific glycoproteins of herpes simplex virus type 1 and type 2
JOURNAL OF INFECTIOUS DISEASES
1996; 174 (5): 899-906
Abstract
T cell recognition of common and type-specific herpes simplex virus (HSV) glycoproteins was measured in 72 subjects. T cells were stimulated with whole HSV-2 antigen and glycoproteins gB2, gD2, and gG2. T cell proliferation in response to HSV-2 antigen and gG2 was significantly higher in subjects with HSV-2 infection than in those with HSV-1 infection only; responses to gB2 and gD2 were the same. T helper (Th) type 1 and Th2 cytokine production in response to whole HSV-2 antigen, gB2, and gD2 was evaluated in 33 subjects. Interleukin (IL)-2 and interferon-gamma responses to most antigens were significantly higher among HSV-2-seropositive subjects than among seronegative subjects. IL-4 synthesis was negligible; IL-10 was produced in seronegative and seropositive persons, but HSV-2 antigen responses were significantly higher in HSV-2-seropositive persons. Naturally acquired immunity to HSV involves T cell recognition of common and type-specific glycoproteins, prominent Th1 responses, and discordant Th2 responses with little IL-4 but substantial IL-10 production.
View details for Web of Science ID A1996VN18100001
View details for PubMedID 8896488
-
Comparison of T-cell responses to measles antigen in infants immunized at 6, 9, and 12 months of age.
OXFORD UNIV PRESS INC. 1996: 269–69
View details for Web of Science ID A1996VN24600315
-
Varicella vaccine in pregnancy.
BMJ (Clinical research ed.)
1996; 313 (7059): 701-702
View details for PubMedID 8819427
View details for PubMedCentralID PMC2352106
-
Immune responses to varicella-zoster virus
INFECTIOUS DISEASE CLINICS OF NORTH AMERICA
1996; 10 (3): 529-?
Abstract
The host response to VZV is critical to the outcome of primary VZV infection. The maintenance of immune memory to the virus is required to prevent symptomatic re-infection on exogenous re-exposure to VZV and to prevent symptomatic reactivation of endogenous virus. Immunization with live varicella (Oka) vaccine elicits primary and memory immunity to VZV. Humoral and cell-mediated host responses induced by the wild-type virus and by the vaccine strain are comparable, which is consistent with the clinical observation that varicella vaccine protects against or significantly reduces the clinical symptoms caused by primary VZV infection. Widespread use of the varicella vaccine in healthy children will yield further knowledge about host-virus interactions, such as the role of exogenous re-exposure in maintaining persistent immunity, which will be relevant to vaccine strategies to prevent other human herpesvirus infections.
View details for Web of Science ID A1996VB58600006
View details for PubMedID 8856351
-
Treatment of adult varicella with sorivudine: A randomized, placebo-controlled trial
JOURNAL OF INFECTIOUS DISEASES
1996; 174 (2): 249-255
Abstract
The antiviral and clinical efficacy of sorivudine in adults with varicella was evaluated in a double-blind, placebo-controlled randomized trial. A total of 186 patients were hospitalized for isolation and treatment within 96 h of rash onset. The diagnosis of varicella was confirmed in 184 patients with paired sera. Patients were randomly assigned to receive 10 or 40 mg of sorivudine or an identical placebo once a day for 5 days. Treatment with 40 mg of sorivudine (compared with placebo) shortened the mean time to 100% crusting from 6.6 to 5.8 days (P = .004) and reduced the mean days that new lesion formed from 3.9 to 3.1 (P = .014). Mean days of cutaneous viral shedding were reduced from 3.3 in the placebo group to 2.6 in the 40-mg sorivudine group (P = .002). The effectiveness of therapy was not affected by the duration of rash before initiation of therapy. Sorivudine is a promising new agent for the treatment of varicella-zoster virus infections.
View details for Web of Science ID A1996UZ09300001
View details for PubMedID 8699051
-
Varicella-zoster virus
CLINICAL MICROBIOLOGY REVIEWS
1996; 9 (3): 361-?
Abstract
Varicella-zoster virus (VZV) is a ubiquitous human alphaherpesvirus that causes varicella (chicken pox) and herpes zoster (shingles). Varicella is a common childhood illness, characterized by fever, viremia, and scattered vesicular lesions of the skin. As is characteristic of the alphaherpesviruses, VZV establishes latency in cells of the dorsal root ganglia. Herpes zoster, caused by VZV reactivation, is a localized, painful, vesicular rash involving one or adjacent dermatomes. The incidence of herpes zoster increases with age or immunosuppression. The VZV virion consists of a nucleocapsid surrounding a core that contains the linear, double-stranded DNA genome; a protein tegument separates the capsid from the lipid envelope, which incorporates the major viral glycoproteins. VZV is found in a worldwide geographic distribution but is more prevalent in temperate climates. Primary VZV infection elicits immunoglobulin G (IgG), IgM, and IgA antibodies, which bind to many classes of viral proteins. Virus-specific cellular immunity is critical for controlling viral replication in healthy and immunocompromised patients with primary or recurrent VZV infections. Rapid laboratory confirmation of the diagnosis of varicella or herpes zoster, which can be accomplished by detecting viral proteins or DNA, is important to determine the need for antiviral therapy. Acyclovir is licensed for treatment of varicella and herpes zoster, and acyclovir, valacyclovir, and famciclovir are approved for herpes zoster. Passive antibody prophylaxis with varicella-zoster immune globulin is indicated for susceptible high-risk patients exposed to varicella. A live attenuated varicella vaccine (Oka/Merck strain) is now recommended for routine childhood immunization.
View details for Web of Science ID A1996UV83900007
View details for PubMedID 8809466
View details for PubMedCentralID PMC172899
-
Varicella-zoster virus: Overview and clinical manifestations
SEMINARS IN DERMATOLOGY
1996; 15 (2): 4-7
Abstract
Varicella-zoster virus (VZV) is a human pathogen that has probably infected humans since prehistoric times. Varicella-zoster virus causes chickenpox in childhood (varicella), and establishes latency in sensory ganglia after the primary infection. Varicella-zoster virus may reemerge later in life, taking advantage of the decline in immune function that occurs with aging. Varicella-zoster virus reactivation causes herpes zoster, commonly known as shingles. The incidence of herpes zoster increases with advancing age. Severe pain is the major cause of acute and chronic morbidity in patients with herpes zoster. Fortunately, the acute phase is self-limiting and transient. However, chronic and often debilitating pain may persist after the lesions have healed and is referred to as postherpetic neuralgia (PHN), the most common complication of herpes zoster. Similar to acute herpes zoster, the incidence of PHN increases dramatically with age.
View details for Web of Science ID A1996UZ94600002
View details for PubMedID 8840410
-
Administration of oral acyclovir suppressive therapy after neonatal herpes simplex virus disease limited to the skin, eyes and mouth: Results of a phase I/II trial
PEDIATRIC INFECTIOUS DISEASE JOURNAL
1996; 15 (3): 247-254
Abstract
Neonatal herpes simplex virus (HSV) infections limited to the skin, eyes and mouth (SEM) can result in neurologic impairment. A direct correlation exists between the development of neurologic deficits and the frequency of cutaneous HSV recurrences. Thus, the National Institutes of Allergy and Infectious Diseases Collaborative Antiviral Study Group conducted a Phase I/II trial of oral acyclovir therapy for the suppression of cutaneous recurrences after SEM disease in 26 neonates.Infants < or = 1 month of age with virologically confirmed HSV-2 SEM disease were eligible for enrollment. Suppressive oral acyclovir therapy (300 mg/m2/dose given either twice daily or three times per day) was administered for 6 months.Twelve (46%) of the 26 infants developed neutropenia (< 1000 cells/mm3) while receiving acyclovir. Thirteen (81%) of the 16 infants who received drug 3 times per day experienced no recurrences of skin lesions while receiving therapy. In comparison, a previous Collaborative Antiviral Study Group study found that only 54% of infants have no cutaneous recurrences in the 6 months after resolution of neonatal HSV disease if oral acyclovir suppressive therapy is not initiated. In one infant, HSV DNA was detected in the cerebrospinal fluid during a cutaneous recurrence, and an acyclovir-resistant HSV mutant was isolated from another patient during the course of the study.Administration of oral acyclovir can prevent cutaneous recurrences of HSV after neonatal SEM disease. The effect of such therapy on neurologic outcome must be assessed in a larger, Phase III study. As such, additional investigation is necessary before routine use of suppressive therapy in this population can be recommended.
View details for Web of Science ID A1996UA25200011
View details for PubMedID 8852914
-
Safety and immunogenicity of one vs two injections of Oka/Merck varicella vaccine in healthy children
PEDIATRIC INFECTIOUS DISEASE JOURNAL
1996; 15 (1): 49-54
Abstract
To compare the safety and immunogenicity of a one- vs. two-dose regimen of Oka/Merck varicella vaccine in approximately 2000 healthy children 12 months to 12 years of age.Subjects with a negative history of varicella were randomized to receive either one or two injections of the vaccine given 3 months apart and were followed for clinical reactions and serologic response (glycoprotein-based enzyme-linked immunosorbent assay).Both one- and two-dose vaccine regimens were generally well-tolerated. The incidences of varicelliform rash and fever were less frequent after the second injection. However, a slight increase in the incidence of injection site reactions was noted after the second injection; these were generally mild. Seroconversion rates by glycoprotein-based enzyme-linked immunosorbent assay were 98.2% (1700 of 1731) after one injection and 99.9% (717 of 718) after two injections. A significant (P < 0.001) boost in geometric mean titers was observed in children who received a second injection of vaccine 3 months after the first injection. Of the children who seroconverted at 6 weeks postregimen (one or two doses as assigned), 99.8% (528 of 529) of the one-dose group and 99.8% (473 of 474) of the two-dose group maintained antibody to varicella at 1 year with geometric mean titers of 19.5 and 31.2, respectively.Administration of a one- or two-dose regimen of the live Oka/Merck varicella vaccine (VARIVAX) is immunogenic and is generally well-tolerated in healthy children 1 to 12 years old. Antibody to varicella persists in > 99% of vaccinees 1 year after vaccination regardless of a one- or two-dose regimen. Long-term follow-up studies of this cohort of children may determine whether a two-dose regimen offers superior protection against chickenpox.
View details for Web of Science ID A1996TQ12400008
View details for PubMedID 8684876
-
Varicella-zoster virus: Aspects of pathogenesis and host response to natural infection and varicella vaccine
ADVANCES IN VIRUS RESEARCH, VOL 46
1996; 46: 263-309
Abstract
Events in the pathogenesis of infection and the host response to VZV are very closely linked. Our experiments demonstrate that CD4- and CD8+ T-lymphocyte populations that are targets of cell-associated VZV viremia also mediate protection against severe infection. Diminished cell-mediated immunity predisposes the host to progressive primary or recurrent VZV disease because infected lymphocytes persist in the circulation and carry the virus to major organs, causing pneumonitis, hepatitis, or other life-threatening complications. The live attenuated varicella vaccine induces cell-mediated immunity and protects against or significantly reduces the morbidity associated with primary VZV infections. The universal administration of varicella vaccine is likely to generate new insights about host-virus interactions, particularly in relation to how VZV immunity is maintained, that will be relevant to the design of vaccines for other human herpesviruses.
View details for Web of Science ID A1996BF08A00006
View details for PubMedID 8824702
-
Live attenuated varicella vaccine
ANNUAL REVIEW OF MICROBIOLOGY
1996; 50: 59-100
Abstract
Varicella-zoster virus (VZV) is a ubiquitous human pathogen that causes varicella, commonly called chicken pox; establishes latency; and reactivates as herpes zoster, referred to as shingles. A live attenuated varicella vaccine, derived from the Oka strain of VZV has clinical efficacy for the prevention of varicella. The vaccine induces persistent immunity to VZV in healthy children and adults. Immunization against VZV also has the potential to lower the risk of reactivation of latent virus. The varicella vaccine may eventually reduce or eliminate herpes zoster, which is a serious problem for elderly and immunocompromised individuals.
View details for Web of Science ID A1996VL56000004
View details for PubMedID 8905076
-
Aspects of the host response to varicella-zoster virus: A review of recent observations
2nd International Conference on the Varicella-Zoster Virus
LITTLE BROWN CO. 1995: S36–S37
View details for Web of Science ID A1995TQ88200013
View details for PubMedID 8545016
-
PERINATAL HERPES - CURRENT STATUS AND OBSTETRIC MANAGEMENT STRATEGIES - THE PEDIATRIC PERSPECTIVE - COMMENTARY
PEDIATRIC INFECTIOUS DISEASE JOURNAL
1995; 14 (10): 832-835
View details for Web of Science ID A1995RZ91200002
-
TROPISM OF VARICELLA-ZOSTER VIRUS FOR HUMAN CD4(+) AND CD8(+) T-LYMPHOCYTES AND EPIDERMAL-CELLS IN SCID-HU MICE
JOURNAL OF VIROLOGY
1995; 69 (9): 5236-5242
Abstract
To investigate the cell tropism and pathogenicity of varicella-zoster virus (VZV) strains, we analyzed VZV replication by using SCID-hu mice that carry human fetal thymus/liver implants under the kidney capsule or as subcutaneous fetal skin implants. MRC-5 cells infected with wild-type VZV or the Oka strain, used in the live attenuated varicella vaccine, were injected into the implants. The implants were surgically removed 2, 7, 14, and 21 days postinfection. The VZV titer from infected thymus/liver implants peaked on day 7 for the wild-type strain and on day 14 for the Oka strain. Histological analysis showed necrotic areas characterized by thymocyte depletion and fibrosis. VZV protein synthesis was detectable by immunohistochemical staining in the necrotic areas and in distant regions that did not show cytopathic changes, and VZV DNA was detected by in situ hybridization in the same distribution. Fluorescence-activated cell sorting analysis of thymocytes harvested at day 7 postinfection showed that VZV proteins were expressed in CD4+, CD8+, and CD4+ CD8+ T cells; VZV was cultured from each T-cell subpopulation. The Oka strain had tropism for human cell types similar to that of wild-type VZV. T lymphocytes released infectious VZV, which is a novel and important observation about the replication of this otherwise highly cell associated virus. VZV-infected skin implants exhibited microscopic epidermal lesions that were indistinguishable histologically from the characteristic lesions of varicella. These experiments demonstrate a unique tropism of VZV for human T lymphocytes, explaining its capacity to cause viremia in natural disease, and demonstrate the value of the SCID-hu model for studies of VZV pathogenesis.
View details for Web of Science ID A1995RN98600004
View details for PubMedID 7636965
View details for PubMedCentralID PMC189355
-
SAFETY, TOLERABILITY, AND IMMUNOGENICITY OF 2 REGIMENS OF OKA/MERCK VARICELLA VACCINE (VARIVAX(R)) IN HEALTHY ADOLESCENTS AND ADULTS
VACCINE
1995; 13 (11): 967-972
Abstract
A multicenter clinical trial was conducted among 757 healthy adolescents and adults, 13-54 years, to compare two regimens of Oka/Merck varicella vaccine with respect to safety, tolerability, and immunogenicity. Participants were randomized to receive two injections of vaccine either four or eight weeks apart and were followed for clinical reactions and serologic response. The two vaccine regimens were equally well tolerated. The seroconversion rates (gpELISA) four weeks after injection 1 and 2 were 72 and 99%, respectively, for those who received vaccine four weeks apart and 78 and 99%, respectively, for those who received vaccine eight weeks apart. The differences in seroconversion rates were not statistically significant. However, delaying the second dose to eight weeks resulted in a higher antibody titer one month after the second injection. Administration of a two-dose regimen of varicella vaccine to susceptible adolescents and adults is well tolerated and highly immunogenic.
View details for Web of Science ID A1995RV51600002
-
SAFETY AND CELLULAR AND HUMORAL IMMUNE-RESPONSES OF A BOOSTER DOSE OF VARICELLA VACCINE 6 YEARS AFTER PRIMARY IMMUNIZATION
JOURNAL OF INFECTIOUS DISEASES
1995; 172 (1): 217-219
Abstract
Four hundred nineteen children and adolescents immunized with live varicella vaccine 4-6 years earlier were enrolled in a study to evaluate the safety and immune response to a booster dose containing approximately 3300 pfu of virus. Of the subjects, 99% (414/419) maintained antibody to varicella zoster virus (VZV) with a geometric mean titer of 25.7 and mean stimulation index (SI) for VZV-specific lymphoproliferation response of 40.3 +/- 5.3 (SE). Some 7-10 days after the booster immunization, seropositivity rates increased to 100% (302/302), and GMT was 143.6 (anamnestic response). At 6 weeks after the booster inoculation, a subset of subjects had 100% seropositivity (74/74) with a GMT of 218.8 and an SI of 58.6. After 3 months, seropositivity was 100% (358/358), GMT was 119.0, and SI was 61.4.
View details for Web of Science ID A1995RF04100030
View details for PubMedID 7797914
-
DIAGNOSIS OF HERPES-SIMPLEX ENCEPHALITIS - APPLICATION OF POLYMERASE CHAIN-REACTION TO CEREBROSPINAL-FLUID FROM BRAIN-BIOPSIED PATIENTS AND CORRELATION WITH DISEASE
JOURNAL OF INFECTIOUS DISEASES
1995; 171 (4): 857-863
View details for Web of Science ID A1995QP91200014
-
AGE-RELATED DIFFERENCES IN CELL-MEDIATED-IMMUNITY TO VARICELLA-ZOSTER VIRUS AMONG CHILDREN AND ADULTS IMMUNIZED WITH LIVE ATTENUATED VARICELLA VACCINE
JOURNAL OF INFECTIOUS DISEASES
1995; 171 (1): 13-17
Abstract
Live attenuated varicella vaccine elicits protection against varicella-zoster virus (VZV), but adults require two doses to achieve optimal seroconversion rates. To assess the potential role of cell-mediated immunity (CMI), T cell proliferation to VZV antigen was compared in children and adults. Mean stimulation indices (SI) in two cohorts of 39 children tested 6 weeks after vaccination were 28.6 +/- 6.21 and 22.1 +/- 3.84, whereas 20 adult vaccines had a mean SI of 9.1 +/- 0.99 (P = .04). Vaccinees had significant increases in CMI after a second dose of vaccine. At 1 year, VZV CMI was significantly lower in adults after two doses (10.0 +/- 1.13 vs. 15.6 +/- 1.77; P = .02), even though 82% of children received one dose. Limitations in the adult helper T cell response to VZV antigens may explain the need for booster doses to elicit effective immunity and the more frequent occurrence of varicella when adult vaccines are exposed to wild type virus.
View details for Web of Science ID A1995PZ87300003
View details for PubMedID 7798653
-
NEW TECHNOLOGY IN THE CLINICAL MICROBIOLOGY LABORATORY - WHAT YOU ALWAYS WANTED TO KNOW BUT WERE AFRAID TO ASK
JOURNAL OF INFECTIOUS DISEASES
1994; 170 (5): 1068-1074
View details for Web of Science ID A1994PN66800002
View details for PubMedID 7963694
-
TUMOR-NECROSIS-FACTOR, INTERLEUKIN-2, AND INTERFERON-GAMMA IN ADULT VARICELLA
JOURNAL OF MEDICAL VIROLOGY
1994; 43 (1): 69-71
Abstract
Adult varicella can be a severe illness complicated by pneumonia, encephalitis, or prolonged fever. This study measured levels of tumor necrosis factor (TNF)-alpha, interleukin-2 (IL-2), and interferon gamma (IFN-G) in a consecutive group of 31 adult varicella patients presenting within 24 hours of rash onset. All cytokines were assayed using an ELISA technique. TNF-alpha was detectable in 71% of patients with a mean level of 52 pg/ml. IL-2 was detectable in 29% with a mean level of 1040 pg/ml. IFN-gamma was detectable in only 9%. There was no correlation between TNF, IL-2, or IFN-G level and clinical severity as determined by duration and severity of cutaneous findings, duration of fever, frequency of hepatitis, or thrombocytopenia.
View details for Web of Science ID A1994NG41500012
View details for PubMedID 8083651
-
WOMEN IN BIOMEDICINE - ENCOURAGEMENT
SCIENCE
1994; 263 (5152): 1357-1358
View details for Web of Science ID A1994MZ92700002
View details for PubMedID 8128213
-
IMMUNIZATION WITH THE IMMEDIATE-EARLY TEGUMENT PROTEIN (OPEN READING FRAME-62) OF VARICELLA-ZOSTER VIRUS PROTECTS GUINEA-PIGS AGAINST VIRUS CHALLENGE
JOURNAL OF VIROLOGY
1993; 67 (12): 7673-7676
Abstract
The IE62 protein, the primary regulatory protein of varicella-zoster virus (VZV) and the major component of the virion tegument, was an effective immunogen in the guinea pig model of VZV infection, whereas the ORF 29 gene product, a nonstructural DNA replication protein, did not elicit protection. All animals immunized with the ORF 29 protein had cell-associated viremia compared with 2 of 11 guinea pigs given the IE62 protein (P = 0.005). VZV was detected in ganglia from 38% of the animals given the ORF 29 protein and 44% of the control animals compared with 9% of the animals immunized with the IE62 protein (P = 0.04). In contrast to the IE62 protein, immunization with the ORF 29 protein did not prime the animals for an enhanced T-cell response upon challenge with infectious virus. The VZV IE62 protein has potential value as a vaccine component.
View details for Web of Science ID A1993MG30700092
View details for PubMedID 8230489
View details for PubMedCentralID PMC238239
-
ANALYSIS OF THE EPIDEMIOLOGY AND PATHOGENESIS OF HERPES-SIMPLEX VIRUS (HSV) INFECTIONS IN PREGNANT-WOMEN AND INFANTS USING THE HSV-2 GLYCOPROTEIN-G ANTIBODY-ASSAY
INFECTIOUS AGENTS AND DISEASE-REVIEWS ISSUES AND COMMENTARY
1993; 2 (6): 375-382
View details for Web of Science ID A1993NH24300003
View details for PubMedID 8012738
-
MULTIFOCAL LEUKOENCEPHALITIS CAUSED BY VARICELLA-ZOSTER VIRUS IN A CHILD WITH LEUKEMIA - SUCCESSFUL TREATMENT WITH ACYCLOVIR
PEDIATRIC INFECTIOUS DISEASE JOURNAL
1993; 12 (5): 402-406
View details for Web of Science ID A1993LC78200011
View details for PubMedID 8392165
-
Detection of antibodies to herpes simplex virus type 2 with a mammalian cell line expressing glycoprotein gG-2.
Clinical and diagnostic virology
1993; 1 (1): 29-38
Abstract
The gene (US4) coding for herpes simplex virus type 2 (HSV-2) glycoprotein G (gG-2) was cloned and constitutively expressed in Chinese hamster ovary (CHO) cells. The expression vector containing the dihydrofolate reductase (dhfr) gene, and the HSV-2 US4 gene under the control of the Simian virus 40 early promoter (SV40 EP), was transfected into dhfr-deficient CHO cells. The transfected cells were selected and amplified using methotrexate (MTX). To demonstrate that the gG-2 produced in these transformed cells had antigenic determinants in common with the native glycoprotein, CHO cells expressing gG-2 were used in an immunofluorescent assay (IFA) for the detection of HSV-2 type-specific antibodies in human serum samples. Seven of eight serum samples from adults with prior episodes of culture proven HSV-2 infections were found to be positive by the IFA method whereas none of seven serum samples from young children with culture documented HSV-1 infections were positive by IFA. Thus the recombinant CHO : gG-2 cells have diagnostic utility in an HSV-2 specific serologic assay.
View details for PubMedID 15566716
-
INVESTIGATION OF THE PATHOGENESIS OF VARICELLA-ZOSTER VIRUS-INFECTION IN GUINEA-PIGS BY USING POLYMERASE CHAIN-REACTION
JOURNAL OF INFECTIOUS DISEASES
1993; 167 (1): 78-83
Abstract
The polymerase chain reaction method (PCR) was used to investigate events in the pathogenesis of varicella-zoster virus (VZV) infection in strain 2, Hartley, and euthymic hairless guinea pigs. VZV was detected in peripheral blood mononuclear cells (PBMC) obtained 2-5 days after infection in 8 (50%) of 16 strain 2, 4 (40%) of 10 hairless, and 10 (34%) of 29 Hartley guinea pigs. The frequency of VZV-infected PBMC was estimated to be at least 1/200,000, which is comparable to that observed in human infection. When VZV PCR was used to test ganglia from hairless guinea pigs, samples from 6 of 8 animals were positive. Of 45 VZV-infected guinea pigs that were tested for cellular immunity by VZV T lymphocyte proliferation assay, 44 developed a stimulation index > 2.0. Control animals had no detectable virus by PCR and did not develop cellular immunity to VZV. These experiments showed that viremia was detectable by PCR during primary VZV infection of guinea pigs in about half of the animals regardless of the strain of guinea pig. Acquisition of cellular immunity provided a consistent marker of infection in all guinea pig strains. PCR was also useful for demonstrating VZV in guinea pig ganglia tissue, with VZV gene sequences being detectable for at least 80 days after infection. With the combination of PCR and immunologic assays, various guinea pig strains should be useful for studies of VZV pathogenesis and for the evaluation of antiviral agents and vaccine strategies.
View details for Web of Science ID A1993KE84600012
View details for PubMedID 8380293
-
THE MANAGEMENT OF PREGNANCIES COMPLICATED BY GENITAL INFECTIONS WITH HERPES-SIMPLEX VIRUS
CLINICAL INFECTIOUS DISEASES
1992; 15 (6): 1031-1038
Abstract
In this review we summarize current knowledge related to the identification of pregnancies that may be complicated by genital herpes and describe the consequences of maternal infections with genital herpes. We address the implications of this information for the management of genital herpes during pregnancy and at delivery and for the care of neonates exposed to herpes simplex virus at delivery. On the basis of the current data, we cannot make specific recommendations concerning many of the clinical problems that are caused by herpes simplex virus infections in pregnant women. We identify and discuss unresolved questions about optimal management.
View details for Web of Science ID A1992JZ60000017
View details for PubMedID 1457634
-
OUTBREAK OF CEFTAZIDIME RESISTANCE DUE TO A NOVEL EXTENDED-SPECTRUM BETA-LACTAMASE IN ISOLATES FROM CANCER-PATIENTS
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
1992; 36 (9): 1991-1996
Abstract
Ceftazidime is widely used in the therapy of infectious complications in neutropenic patients. We studied an outbreak of ceftazidime-resistant gram-negative bacillary infections in pediatric cancer patients receiving empirical ceftazidime therapy for neutropenic fever. Fourteen isolates (12 Klebsiella pneumoniae and 2 Escherichia coli) from 13 patients were studied. Specimens were obtained from multiple clinical sites including blood, urine, throat, and lung. The organisms were resistant to ceftazidime, aztreonam, and penicillins but remained susceptible to cephamycins and imipenem. All resistant isolates produced a novel beta-lactamase (TEM-26) with a pI of approximately 5.58, which was transferred by transformation to E. coli on a 7.9-kb nonconjugative plasmid which cotransferred resistance to trimethoprim-sulfamethoxazole. This enzyme readily hydrolyzed ceftazidime, aztreonam, and penicillins in a spectrophotometric assay. DNA sequencing data suggest that TEM-26 is derived from TEM-1.
View details for Web of Science ID A1992JM24700033
View details for PubMedID 1416892
-
PREVENTING NEONATAL HERPES - REPLY
NEW ENGLAND JOURNAL OF MEDICINE
1992; 327 (9): 648-648
View details for Web of Science ID A1992JK20400027
-
CELL-MEDIATED-IMMUNITY TO VARICELLA-ZOSTER VIRUS
JOURNAL OF INFECTIOUS DISEASES
1992; 166: S35-S41
Abstract
Natural varicella-zoster virus (VZV) infection and immunization with live attenuated varicella vaccine elicits T lymphocytes that recognize VZV glycoproteins, gpI-V, and the immediate early/tegument protein, the product of gene 62 (IE62). Proliferation or cytotoxicity assays, done under limiting dilution conditions to estimate responder cell frequencies, indicate no preferential recognition of VZV proteins by human T cells. Analysis of the primary cytotoxic T lymphocyte (CTL) response after vaccination demonstrates that both gpI and IE62 are targets of the early response. CD4(+)- and CD8(+)-mediated CTL recognition of these viral proteins can be detected with natural and vaccine-induced immunity. Responder cell frequencies for protein-specific T cell proliferation and CTL function are generally comparable in subjects with natural and vaccine-acquired immunity to VZV. Exogenous reexposure to VZV results in enhanced T cell proliferation and may be an important mechanism for maintaining virus-specific cellular immunity. Providing exogenous reexposure by giving varicella vaccine to individuals who have preexisting natural immunity markedly increases the responder cell frequencies of T cells that proliferate in response to VZV antigen and the numbers of circulating CTL that recognize VZV proteins.
View details for Web of Science ID A1992JF56100006
View details for PubMedID 1320649
-
COMPARISON OF THE WESTERN IMMUNOBLOT ASSAY AND A GLYCOPROTEIN-G ENZYME-IMMUNOASSAY FOR DETECTION OF SERUM ANTIBODIES TO HERPES-SIMPLEX VIRUS TYPE-2 IN PATIENTS WITH AIDS
JOURNAL OF CLINICAL MICROBIOLOGY
1992; 30 (5): 1312-1314
Abstract
Herpes simplex virus type 2 (HSV-2) seroprevalence in 68 patients with AIDS was 77% by Western blot (immunoblot) and 44% by glycoprotein G-2 immunoassay. Each of 16 patients with culture-proven HSV-2 infection was positive by Western blot versus 8 by glycoprotein G-2 immunoassay. No differences in age, race, duration of AIDS, acyclovir usage, or HSV-1 seroprevalence were found to explain differences in sensitivity.
View details for Web of Science ID A1992HP82800052
View details for PubMedID 1316370
View details for PubMedCentralID PMC265273
-
KINETICS AND VIRAL PROTEIN SPECIFICITY OF THE CYTOTOXIC LYMPHOCYTE-T RESPONSE IN HEALTHY-ADULTS IMMUNIZED WITH LIVE ATTENUATED VARICELLA VACCINE
JOURNAL OF INFECTIOUS DISEASES
1992; 165 (5): 852-858
Abstract
The cytotoxic T lymphocyte (CTL) response was evaluated in adults given live attenuated varicella vaccine, using target cells expressing varicella-zoster virus (VZV) immediate-early protein (IE62) or VZV glycoproteins gpI, gpIV, or gpV to determine viral protein specificity. The frequency of CTL that recognized IE62 was 1:171,000 +/- 46,000 SE in subjects tested 10 days to 8 weeks after the initial vaccine dose; the induction of CTL specific for gpI was equivalent. CTL recognition of VZV proteins was mediated by CD4+ or CD8+ cells. CTL recognition of IE62 and gpIV persisted in vaccinees (tested approximately 4 years later) and was comparable to that in the naturally immune. The mean frequency of CTL specific for gpV was lower (but not significantly) in vaccinees than in naturally immune subjects. Assay of responder cell frequencies showed persistence of equivalent numbers of T lymphocytes that recognized IE62 and gpI in vaccinees and naturally immune subjects. Immunization with this vaccine elicited memory T lymphocyte responses to VZV comparable to those induced by natural infection.
View details for Web of Science ID A1992HQ27500010
View details for PubMedID 1314871
-
ACYCLOVIR IN CHICKENPOX - REPLY
NEW ENGLAND JOURNAL OF MEDICINE
1992; 326 (18): 1225-1226
View details for Web of Science ID A1992HR00800027
-
IDENTIFICATION OF WOMEN AT UNSUSPECTED RISK OF PRIMARY INFECTION WITH HERPES-SIMPLEX VIRUS TYPE-2 DURING PREGNANCY
NEW ENGLAND JOURNAL OF MEDICINE
1992; 326 (14): 916-920
Abstract
Primary infections with herpes simplex virus type 2 (HSV-2) acquired by women during pregnancy account for about half of the morbidity and mortality from HSV-2 among neonates. The other half results from reactivation of old infections. Better methods are needed to identify which women are at risk for primary HSV-2 infection.We prospectively studied HSV-2 infections among pregnant women who were patients in private obstetrical practices. Using an enzyme-linked immunosorbent assay that detects type-specific antibodies to HSV-2 glycoprotein G, we determined the prevalence at base line of HSV-2 infections among pregnant women and their husbands, the frequency of discordance for infection between partners, and the risk of seroconversion during pregnancy among the seronegative women whose husbands were seropositive.The seroprevalence of HSV-2 was 32 percent among the 277 women followed throughout their pregnancies and 25 percent among the 190 husbands studied. Two thirds of the HSV-2-seropositive women had no history of genital herpes. Of the 190 couples, 139 (73 percent) were serologically concordant for HSV-2 antibodies (57 percent being seronegative and 16 percent being seropositive), whereas 51 couples (27 percent) were discordant, despite having been sexually intimate for a mean of 6.1 years. Eighteen women who were seronegative for HSV-2 (9.5 percent) had seropositive partners, of whom 10 (56 percent) had no history of genital herpes. Thus, approximately 5 percent of these pregnant women had an unsuspected risk of contracting a primary HSV-2 infection. One of the 18 seronegative women with a seropositive husband seroconverted to HSV-2 during pregnancy; none of the other women seroconverted.In this study about 10 percent of pregnant women were at risk of contracting a primary HSV-2 infection from their HSV-2-seropositive husbands. In addition, about a third of these women were seropositive for HSV-2 and thus at risk for asymptomatic, reactivated infections. Serologic testing of couples can identify women who are at risk for primary or reactivated HSV-2 infections during pregnancy.
View details for Web of Science ID A1992HL26100003
View details for PubMedID 1311799
-
Immunity in strain 2 guinea-pigs inoculated with vaccinia virus recombinants expressing varicella-zoster virus glycoproteins I, IV, V or the protein product of the immediate early gene 62.
journal of general virology
1992; 73 : 811-819
Abstract
The immunogenicity of specific varicella-zoster virus (VZV) proteins, with emphasis upon cell-mediated immune responses, was evaluated by immunizing strain 2 guinea-pigs with vaccinia virus recombinants that express gpI (vac-gpI), gpIV (vac-gpIV) and gpV (vac-gpV) or the IE-62 protein (vac-IE-62). Vac-gpI elicited the highest initial mean T cell proliferation response [stimulation index (S.I.) 3.8 +/- 0.9 S.E.M.] whereas inoculation with vac-gpV produced the lowest primary T cell response (S.I. 2.5 +/- 1.1 S.E.M.). T cell proliferation was detected for a shorter period after immunization with vac-gpV compared to vac-gpI, vac-gpIV or vac-IE-62. A comparison of the immunogenicity of vac-gpI and vac-IE-62 with the same proteins prepared by immunoaffinity purification showed that immunization with these proteins in either form elicited virus-specific IgG antibodies and T cell recognition. The presence or absence of IgG antibodies to the IE-62 protein was used to assess protection against challenge with guinea-pig cell-adapted infectious VZV in animals that had been inoculated with vac-gpI, vac-gpIV or vac-gpV. Immunization with vac-gpI and vac-gpIV restricted VZV replication but all animals given vac-gpV developed antibodies to IE-62 after challenge with infectious VZV. Priming of the T lymphocyte response was observed in all animals immunized with VZV-vaccinia virus recombinants after subsequent exposure to infectious VZV. These experiments with VZV vac-gpI, vac-gpIV and vac-gpV in guinea-pigs suggest variability in the capacity of herpesviral glycoproteins to elicit cell-mediated immunity in vivo. Induction of virus-specific immunity using IE-62 means that this major tegument protein of VZV could be a useful component for vaccine development.
View details for PubMedID 1321876
-
IMMUNITY IN STRAIN-2 GUINEA-PIGS INOCULATED WITH VACCINIA VIRUS RECOMBINANTS EXPRESSING VARICELLA-ZOSTER VIRUS GLYCOPROTEINS-I, GLYCOPROTEIN-IV, GLYCOPROTEIN-V OR THE PROTEIN PRODUCT OF THE IMMEDIATE EARLY GENE-62
JOURNAL OF GENERAL VIROLOGY
1992; 73: 811-819
View details for Web of Science ID A1992HM86100008
-
Herpes simplex virus infections: the genital tract and the newborn.
Pediatrics in review
1992; 13 (3): 107-112
View details for PubMedID 1565589
-
Investigation of varicella-zoster virus infection by polymerase chain reaction in the immunocompetent host with acute varicella.
journal of infectious diseases
1992; 165 (1): 188-?
View details for PubMedID 1309373
-
SUBCLINICAL VARICELLA-ZOSTER VIRUS VIREMIA, HERPES-ZOSTER, AND LYMPHOCYTE-T IMMUNITY TO VARICELLA-ZOSTER VIRAL-ANTIGENS AFTER BONE-MARROW TRANSPLANTATION
JOURNAL OF INFECTIOUS DISEASES
1992; 165 (1): 119-126
Abstract
Bone marrow transplant (BMT) recipients were evaluated for subclinical varicella-zoster virus (VZV) viremia and symptoms of herpes zoster after transplantation. Viremia was demonstrated by testing peripheral blood mononuclear cells using polymerase chain reaction and was documented in 19% of 37 patients. When reactivation was defined as herpes zoster and/or subclinical VZV viremia, 41% of VZV-seropositive BMT recipients experienced VZV reactivation. None of 12 patients tested before VZV reactivation had T lymphocyte proliferation to VZV antigen (mean stimulation index, 1.0 +/- 0.42 [SD] at less than 100 days; 12.0 +/- 6.03 at greater than 100 days [P = .003]). Among patients tested at greater than 100 days, 5 (63%) of 8 with detectable T cell proliferation had subclinical or clinical VZV reactivation compared with none of 6 who lacked VZV T cell responses. Recovery of VZV-specific cytotoxic T lymphocyte function was observed in 50% of BMT patients, but BMT recipients had significantly fewer circulating cytotoxic T lymphocytes that recognized VZV immediate early protein (P = .03) or glycoprotein I (P = .004) than did healthy VZV immune subjects. In vivo reexposure to VZV antigens due to subclinical VZV viremia or symptomatic VZV reactivation may explain the recovery of virus-specific T cell immunity after BMT.
View details for Web of Science ID A1992GW58200016
View details for PubMedID 1309369
-
THE VARICELLA-ZOSTER VIRUS IMMEDIATE-EARLY PROTEIN IE62 IS A MAJOR COMPONENT OF VIRUS-PARTICLES
JOURNAL OF VIROLOGY
1992; 66 (1): 359-366
Abstract
Varicella-zoster virus (VZV) open reading frame (ORF) 62 potentially encodes a protein with considerable amino acid homology to the herpes simplex virus (HSV) immediate-early regulatory polypeptide ICP4 (or IE3). To identify and characterize its protein product(s) (IE62), we used a rabbit antiserum prepared against a synthetic peptide corresponding to the C-terminal 13 amino acids of the predicted protein. This antiserum reacted with phosphorylated polypeptides of 175 to 180 kDa that were made in VZV-infected cells and in cells infected with a vaccinia virus recombinant expressing IE62, but not in control-infected cells, confirming its specificity and reactivity to the IE62 protein. The antiserum recognized a 175-kDa polypeptide in purified virions that comigrated with a major structural protein. Comparison of this reactivity with that of an antipeptide antiserum directed against the VZV ORF 10 product (homologous to the HSV major structural protein VP16) indicates similar levels of ORF 62 and ORF 10 polypeptides in VZV virions. In contrast, antipeptide antiserum directed against the VZV ORF 29 product, the homolog of the HSV major DNA-binding protein, failed to recognize any protein in our virion preparations. Treatment of virions with detergents that disrupt the virion envelope did not dissociate IE62 from the nucleocapsid-tegument structure of the virion. Differential sensitivity of VZV virion IE62 to trypsin digestion in the presence or absence of Triton X-100 indicates that IE62 is protected from trypsin degradation by the virus envelope; since it is not a nucleocapsid protein, we conclude that it is part of the tegument. Finally, we show that the virion 175-kDa protein either can autophosphorylate or is a major substrate in vitro for virion-associated protein kinase activity.
View details for Web of Science ID A1992GU97100044
View details for PubMedID 1309252
View details for PubMedCentralID PMC238295
-
A CONTROLLED TRIAL OF ACYCLOVIR FOR CHICKENPOX IN NORMAL-CHILDREN
NEW ENGLAND JOURNAL OF MEDICINE
1991; 325 (22): 1539-1544
Abstract
Chickenpox, the primary infection caused by the varicella-zoster virus, affects more than 3 million children a year in the United States. Although usually self-limited, chickenpox can cause prolonged discomfort and is associated with infrequent but serious complications.To evaluate the effectiveness of acyclovir for the treatment of chickenpox, we conducted a multicenter, double-blind, placebo-controlled study involving 815 healthy children 2 to 12 years old who contracted chickenpox. Treatment with acyclovir was begun within the first 24 hours of rash and was administered by the oral route in a dose of 20 mg per kilogram of body weight four times daily for five days.The children treated with acyclovir had fewer varicella lesions than those given placebo (mean number, 294 vs 347; P less than 0.001), and a smaller proportion of them had more than 500 lesions (21 percent, as compared with 38 percent with placebo; P less than 0.001). In over 95 percent of the recipients of acyclovir no new lesions formed after day 3, whereas new lesions were forming in 20 percent of the placebo recipients on day 6 or later. The recipients of acyclovir also had accelerated progression to the crusted and healed stages, less itching, and fewer residual lesions after 28 days. In the children treated with acyclovir the duration of fever and constitutional symptoms was limited to three to four days, whereas in 20 percent of the children given placebo illness lasted more than four days. There was no significant difference between groups in the distribution of 11 disease complications (10 bacterial skin infections and 1 case of transient cerebellar ataxia). Acyclovir was well tolerated, and there was no significant difference between groups in the titers of antibodies against varicella-zoster virus.Acyclovir is a safe treatment that reduces the duration and severity of chickenpox in normal children when therapy is initiated during the first 24 hours of rash. Whether treatment with acyclovir can reduce the rare, serious complications of chickenpox remains uncertain.
View details for Web of Science ID A1991GR38000003
View details for PubMedID 1944438
-
RELATIONSHIPS BETWEEN MATERNAL IMMUNITY TO HERPES-SIMPLEX VIRUS AND THE RISK OF NEONATAL HERPESVIRUS-INFECTION
WORKSHOP ON HERPES SIMPLEX VIRUS VACCINE
UNIV CHICAGO PRESS. 1991: S953–S956
Abstract
Current seroepidemiologic studies performed with assays that measure type-specific antibodies to herpes simplex virus (HSV) type 2 have demonstrated that infection due to the virus is common among women of child-bearing age. With regard to perinatal transmission of HSV, the virus infects nearly 50% of infants whose mothers have primary genital herpes, whereas less than 5% of infants exposed to recurrent maternal infection at the time of delivery become infected. Maternal immunity may also influence the clinical manifestations of neonatal herpes, with primary maternal infection more likely to be associated with disseminated disease in the infant. An effective HSV vaccine could alter the prevalence of neonatal herpes by (1) reducing women's risk of acquiring primary genital herpes during pregnancy and (2) boosting immunity in mothers for whom serologic evidence of previous infection due to HSV type 2 has been noted, which will enhance the transplacental transfer of virus-specific antibodies.
View details for Web of Science ID A1991GV62600014
View details for PubMedID 1664133
-
Human T cells recognize multiple epitopes of an immediate early/tegument protein (IE62) and glycoprotein I of varicella zoster virus.
Viral immunology
1991; 4 (3): 151-166
Abstract
Infection with varicella zoster virus (VZV) elicits persistent cell-mediated immunity directed against the immediate early (IE62) protein and the glycoprotein I (gp I) in most healthy subjects. In these experiments, synthetic peptides corresponding to residues of the IE62 protein and gp I were used to identify linear amino acid sequences of these immunogenic VZV proteins that were recognized by peripheral blood T lymphocytes from VZV-immune individuals of known major histocompatibility complex (MHC) type. All of 12 VZV-immune donors had T-cell proliferative responses, defined as a stimulation index (SI) greater than or equal to 2.0, to at least two of ten synthetic IE62 peptides; the mean number of IE62 peptides recognized by T cells from VZV-immune donors was seven. Five of the ten IE62 peptides stimulated T cells from 75% to 83% of the VZV-immune donors; the other five IE62 peptides were recognized by T cells from 42% to 67% of the subjects. All VZV-immune donors also had T proliferation responses to at least two of ten synthetic gp I peptides; the mean number of peptides recognized was six. Six of the ten gp I peptides were recognized by T cells from 67% to 92% of the VZV-immune donors; the frequency of donors responding to the other gp I peptides ranged from 42% to 58%. None of five nonimmune donors demonstrated T-cell proliferation to any of the IE62 or gp I peptides. A combination of two IE62 peptides provided epitopes that could be recognized by T cells from all twelve VZV-immune donors, regardless of DR type. Similarly, one gp I peptide in combination with either of two other gp I peptides induced proliferation of T cells from all immune subjects. Memory T cells with specificity for multiple short amino acid sequences of the IE62 protein and gp I were detected in subjects who had had primary VZV infection more than 20 years earlier. These observations indicate that natural VZV infection elicits a diverse cell-mediated immune response to viral proteins that is not restricted to only one or two immunodominant regions. Although the usefulness of peptide vaccines remains to be established, multiple epitopes of the IE62 protein and gp I were identified that could be presented by antigen-presenting cells (APC) and recognized by T cells from most subjects in an "outbred" human population.
View details for PubMedID 1725699
-
MAJOR HISTOCOMPATIBILITY COMPLEX RESTRICTION OF T-CELL RESPONSES TO VARICELLA-ZOSTER VIRUS IN GUINEA-PIGS
JOURNAL OF VIROLOGY
1991; 65 (3): 1491-1495
Abstract
Varicella-zoster virus (VZV), adapted to grow in guinea pig fibroblasts, was injected subcutaneously into Hartley, strain 2, and strain 13 guinea pigs. Serum immunoglobulin G antibodies were detected 2 weeks later, and T-cell proliferative responses by blood lymphocytes were found 3 weeks after injection. The proliferating cells bound the 155 antibody, which defines a CD4-like subset of guinea pig T lymphocytes. VZV-infected fibroblasts of human, Hartley, and strain 13 origin elicited equivalent amounts of proliferation, which was quantitatively greater than that obtained with an extracted VZV antigen. Uninfected (control) human or guinea pig fibroblasts did not elicit T-cell proliferation. The proliferative response to VZV required the presence of autologous (strain 2 or 13) antigen-presenting cells and was blocked by the addition of an anti-class II major histocompatibility complex antibody. Effector cells obtained from in vitro cultures mediated class II-restricted cytotoxicity to L2C cells incubated with VZV. Class I-restricted responses were obtained only by cross-priming strain 2 animals with strain 13 peritoneal exudate cells which had been preincubated with VZV. The data indicate that guinea pigs resemble humans in that class II-restricted T cells with specificity for VZV are more readily cultured from blood than are class I-restricted cells.
View details for Web of Science ID A1991EY75000051
View details for PubMedID 1847466
View details for PubMedCentralID PMC239929
-
Predictors of morbidity and mortality in neonates with herpes simplex virus infections. The National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group.
New England journal of medicine
1991; 324 (7): 450-454
Abstract
In a controlled trial comparing acyclovir with vidarabine in the treatment of neonatal herpes simplex virus (HSV) infection, we found no significant difference between the treatments in adjusted mortality and morbidity. Hence, we sought to define for the entire cohort (n = 202) the clinical characteristics that best predicted the eventual outcome in these neonates.Data were gathered prospectively at 27 centers between 1981 and 1988 in infants less than one month of age who had virologically confirmed HSV infection. We examined the outcomes by multivariate analyses of 24 variables. Disease was classified in one of three categories based on the extent of the involvement at entry into the trial: infection confined to skin, eyes, or mouth; encephalitis; or disseminated infection.There were no deaths among the 85 infants with localized HSV infection. The mortality rate was significantly higher in the 46 neonates with disseminated infection (57 percent) than in the 71 with encephalitis (15 percent). In addition, the risk of death was increased in neonates who were in or near coma at entry (relative risk, 5.2), had disseminated intravascular coagulopathy (relative risk, 3.8), or were premature (relative risk, 3.7). In babies with disseminated disease, HSV pneumonitis was also associated with greater mortality (relative risk, 3.6). In the survivors, morbidity was most frequent in infants with encephalitis (relative risk, 4.4), disseminated infection (relative risk, 2.1), seizures (relative risk, 3.0), or infection with HSV type 2 (relative risk, 4.9). With HSV infection limited to the skin, eyes, or mouth, the presence of three or more recurrences of vesicles was associated with an increased risk of neurologic impairment as compared with two or fewer recurrences.
View details for PubMedID 1988830
-
A CONTROLLED TRIAL COMPARING VIDARABINE WITH ACYCLOVIR IN NEONATAL HERPES-SIMPLEX VIRUS-INFECTION
NEW ENGLAND JOURNAL OF MEDICINE
1991; 324 (7): 444-449
View details for Web of Science ID A1991EX36300003
-
PREDICTORS OF MORBIDITY AND MORTALITY IN NEONATES WITH HERPES-SIMPLEX VIRUS-INFECTIONS
NEW ENGLAND JOURNAL OF MEDICINE
1991; 324 (7): 450-454
View details for Web of Science ID A1991EX36300004
-
A controlled trial comparing vidarabine with acyclovir in neonatal herpes simplex virus infection. Infectious Diseases Collaborative Antiviral Study Group.
New England journal of medicine
1991; 324 (7): 444-449
Abstract
Despite the use of vidarabine, herpes simplex virus (HSV) infection in neonates continues to be a disease of high morbidity and mortality. We undertook a controlled trial comparing vidarabine with acyclovir for the treatment of neonatal HSV infection.Babies less than one month of age with virologically confirmed HSV infection were randomly and blindly assigned to receive either intravenous vidarabine (30 mg per kilogram of body weight per day; n = 95) or acyclovir (30 mg per kilogram per day; n = 107) for 10 days. Actuarial rates of mortality and morbidity among the survivors after one year were compared overall and according to the extent of the disease at entry into the study (infection confined to the skin, eyes, or mouth; encephalitis; or disseminated disease).After adjustment for differences between groups in the extent of disease, there was no difference between vidarabine and acyclovir in either morbidity (P = 0.83) or mortality (P = 0.27). None of the 85 babies with disease confined to the skin, eyes, or mouth died. Of the 31 babies in this group who were treated with vidarabine and followed for a year, 88 percent (22 of 25) were judged to be developing normally after one year, as compared with 98 percent (45 of 46) of the 54 treated with acyclovir (95 percent confidence interval for the difference, -4 to 24). For the 71 babies with encephalitis, mortality was 14 percent with vidarabine (5 of 36) and with acyclovir (5 of 35); of the survivors, 43 percent (13 of 30) and 29 percent (8 of 28), respectively, were developing normally after one year (95 percent confidence interval for the difference, -11 to 39). For the 46 babies with disseminated disease, mortality was 50 percent (14 of 28) with vidarabine and 61 percent (11 of 18) with acyclovir (95 percent confidence interval for the difference, -20 to 40); of the survivors, 58 percent (7 of 12) and 60 percent (3 of 5), respectively, were judged to be developing normally after one year (95 percent confidence interval for the difference, -40 to 50). Both medications were without serious toxic effects.In this multicenter, randomized, blinded study there were no differences in outcome between vidarabine and acyclovir in the treatment of neonatal HSV infection. The study lacked statistical power to determine whether there were sizable differences within the subgroups of those with localized HSV, encephalitis, or disseminated disease.
View details for PubMedID 1988829
-
PHARMACOKINETICS OF ACYCLOVIR IN THE TERM HUMAN-PREGNANCY AND NEONATE
AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY
1991; 164 (2): 569-576
Abstract
Concern about neonatal herpes often leads to cesarean delivery of infants in women with a history of genital herpes. The antiviral drug acyclovir has been used effectively to suppress genital herpes simplex virus recurrences in nonpregnant adults. Its administration to pregnant women with recurrent genital herpes may reduce herpes simplex virus recurrences and thus may decrease the cesarean section rate among this population. To study the pharmacokinetics, safety, and patient tolerance of suppressive oral acyclovir, either 200 mg (n = 7) or 400 mg (n = 8) was administered orally every 8 hours to pregnant women with a history of recurrent herpes simplex virus, from 38 weeks' gestation until delivery. The mean +/- SD plasma levels for the 200 and 400 mg groups, respectively, were: first dose peak, 1.7 +/- 0.6 and 2.3 +/- 1.0 mumol/L; steady-state trough, 0.7 +/- 0.3 and 0.8 +/- 0.6 mumol/L; steady-state peak, 1.9 +/- 1.0 and 3.3 +/- 1.0 mumol/L. In late gestation maternal acyclovir pharmacokinetics were similar to those of nonpregnant adults from other studies. Acyclovir was concentrated in the amniotic fluid; however, there was no accumulation in the fetus (mean maternal/infant plasma ratio at delivery was 1.3). Acyclovir was well tolerated, and no toxicity was seen in the mothers or infants. The administration of acyclovir, 400 mg every 8 hours, appears appropriate for use in an efficacy and safety study regarding suppression of herpes simplex virus recurrences during the last weeks of pregnancy.
View details for Web of Science ID A1991EX76500023
View details for PubMedID 1847004
-
LACK OF TRANSMISSION OF THE LIVE ATTENUATED VARICELLA VACCINE VIRUS TO IMMUNOCOMPROMISED CHILDREN AFTER IMMUNIZATION OF THEIR SIBLINGS
PEDIATRICS
1991; 87 (2): 166-170
Abstract
The safety of administering the live attenuated Oka/Merck varicella vaccine to the well siblings of children with malignancy was evaluated as a strategy for reducing the risk of household exposure to varicella among immunocompromised children. Susceptible well children were eligible for vaccination if the child with malignancy had leukemia, lymphoma, or solid tumor in remission for 3 months or longer. No evidence of vaccine virus transmission was found among 30 children with malignancy whose 37 healthy susceptible siblings were immunized with varicella vaccine. Varicella-zoster virus was not isolated from the oropharyngeal secretions taken from 17 vaccinees or their 14 immunocompromised siblings. None of the 30 immunocompromised children had vaccine-related rashes or showed immunologic evidence of subclinical varicella-zoster virus infection based on testing for varicella-zoster virus IgG antibodies and T-lymphocyte proliferation to varicella-zoster virus. Four healthy vaccinees eventually had mild breakthrough cases of varicella, with transmission to the high-risk sibling in 3 cases. However, even in these families, the immunocompromised children had been protected from household exposure varicella for at least 20 months early in the course of their immunosuppressive treatment.
View details for Web of Science ID A1991EW34200008
View details for PubMedID 1846236
-
EQUIVALENT RECOGNITION OF A VARICELLA-ZOSTER VIRUS IMMEDIATE EARLY PROTEIN (IE62) AND GLYCOPROTEIN-I BY CYTOTOXIC LYMPHOCYTES-T OF EITHER CD4+ OR CD8+ PHENOTYPE
JOURNAL OF IMMUNOLOGY
1991; 146 (1): 257-264
Abstract
Immunity to varicella-zoster virus (VZV), a member of the alpha-herpes virus family, exemplifies the host response to an ubiquitous human viral pathogen. In this investigation of the cytotoxic T lymphocyte (CTL) response to VZV, the depletion of CD4+ T lymphocytes made it possible to demonstrate CD8(+)-mediated cytotoxic function against autologous VZV-infected lymphoblastoid cells targets. CTL recognition of two major VZV proteins, the immediate early protein (IE62) and gp I, was demonstrated in limiting dilution cultures of T lymphocytes obtained from immune donors, stimulated with inactivated VZV Ag, and tested against lymphoblastoid cells infected with vaccinia recombinants expressing these VZV proteins. Among 11 VZV donors tested at least 20 y after primary infection, the mean precursor frequency for T lymphocytes that recognized the IE62 protein was 1:105,000 +/- 85,000 SD, with a range of 1:13,000 to 1:231,000. The mean frequency of CTL precursors specific for gp I in 11 subjects was equivalent, with a mean of 1:121,000 +/- 86,000 SD (range 1:15,000 to 1:228,000) (p = 0.68). Limiting dilution cultures were also prepared using purified CD4+ or CD8+ T lymphocyte populations recovered from PBMC by sterile fluorescence-activated cell sorting. CTL precursors that recognized the IE62 protein or gp I were derived from each of the major T lymphocyte populations by stimulation with inactivated VZV Ag; CD4+ and CD8+ CTL precursor frequencies for the IE62 protein and gp I were equivalent (p = 0.2). We conclude that antiviral CTL activity against targets expressing VZV proteins was mediated equally well by T lymphocytes of the CD4+ or CD8+ phenotype and that antiviral CTL function could be elicited in each subpopulation by exposure to non-infectious viral Ag.
View details for Web of Science ID A1991EQ34000042
View details for PubMedID 1670603
-
USE OF POLYMERASE CHAIN-REACTION FOR SUCCESSFUL IDENTIFICATION OF ASYMPTOMATIC GENITAL-INFECTION WITH HERPES-SIMPLEX VIRUS IN PREGNANT-WOMEN AT DELIVERY
JOURNAL OF INFECTIOUS DISEASES
1990; 162 (5): 1031-1035
Abstract
The polymerase chain reaction was adapted to the amplification of a herpes simplex virus (HSV) DNA sequence, common to HSV types 1 and 2 (HSV-1, HSV-2). The amplified product was detectable by ethidium-bromide staining or Southern hybridization of gels and by dot hybridization. The HSV polymerase chain reaction detected HSV DNA in samples obtained from eight patients with genital lesions from which HSV-2 was isolated in tissue culture and from four patients with labial lesions from which HSV-1 was isolated. The HSV polymerase chain reaction identified HSV in clinical specimens obtained from 11 women who had asymptomatic genital HSV infections at delivery. None of 11 samples obtained at delivery from women who had antibodies to HSV-2, but whose delivery cultures were negative, were positive by polymerase chain reaction and no false-positive reactions were obtained when the reaction mixture contained human cell DNA or varicella-zoster virus, cytomegalovirus, Epstein-Barr virus, or human papillomavirus DNA.
View details for Web of Science ID A1990EE04600005
View details for PubMedID 2172392
-
THE IMMUNOGENICITY OF THE OKA MERCK VARICELLA VACCINE IN RELATION TO INFECTIOUS VARICELLA-ZOSTER VIRUS AND RELATIVE VIRAL-ANTIGEN CONTENT
JOURNAL OF INFECTIOUS DISEASES
1990; 162 (5): 1049-1054
Abstract
Humoral and cellular immune responses to whole varicella-zoster virus (VZV) antigen and to the VZV glycoprotein I (gpI) and immediate early protein (IE-62) were compared in two populations of healthy children who received different lots of the Oka/Merck varicella vaccine. Children who were given vaccine containing 950 pfu with a relative antigen content of 1.0 (lot C-K472) per dose, in an earlier protocol, had an initial seroconversion rate of 87% but VZV cell-mediated immunity was diminished at 8 weeks and 1 year after immunization. At 1 year, the percentage of vaccinees with T lymphocyte proliferation to whole VZV, gpI, or IE-62 was 98%, 77%, and 83% for recipients of the 1140 pfu/1.7 relative antigen or 1145 pfu/1.6 relative antigen content vaccines compared with 43%, 40%, and 40% among those given the vaccine with 950 pfu/1.0 relative antigen content. Since the more immunogenic vaccines contained 1.5-2.0 times more viral antigen and only 20% more infectious virus, viral antigen content may affect the immunogenicity of the varicella vaccine, particularly as reflected in the cell-mediated immune response. The current vaccine preparations elicited cellular and humoral immune responses to whole VZV antigen and memory T lymphocytes specific for major viral proteins that were detectable 1 year after immunization.
View details for Web of Science ID A1990EE04600008
View details for PubMedID 2172393
-
HERPES-SIMPLEX VIRUS-INFECTIONS
SYMP ON PERINATAL INFECTIOUS DISEASES : UPDATE 1990
LIPPINCOTT WILLIAMS & WILKINS. 1990: 765–67
View details for Web of Science ID A1990EC31500024
View details for PubMedID 2235158
-
ACYCLOVIR TREATMENT FOR VARICELLA DOES NOT LOWER GPI AND IE-62 (P170) ANTIBODY-RESPONSES TO VARICELLA-ZOSTER VIRUS IN NORMAL-CHILDREN
JOURNAL OF CLINICAL MICROBIOLOGY
1990; 28 (10): 2327-2330
Abstract
The varicella-zoster virus (VZV) membrane glycoprotein gpI elicits a major immunoglobulin G antibody response after naturally acquired VZV infection; antibody to a nonglycosylated immediate-early protein, IE-62 (p170), represents a response to a nonmembrane VZV component. We evaluated antibody response to VZV gpI and IE-62 (p170) at 28 days and 1 year following infection in 34 children (ages 5 to 16 years) enrolled in a randomized placebo-controlled study of oral acyclovir for the treatment of varicella. All children were VZV antibody negative at enrollment, were previously healthy, and had laboratory-documented varicella. Compared with placebo recipients, acyclovir recipients had lower geometric mean titers by the fluorescent antibody to membrane antigen technique at 28 days (620 versus 836) but similar titers at 1 year (122 versus 122). All children had antibodies to gpI and IE-62 detectable by enzyme-linked immunosorbent assay at 28 days and 1 year. No difference in gpI at 28 days compared with 1 year was noted in acyclovir recipients. No difference in antibody to IE-62 (p170) was noted when acyclovir and placebo recipients were compared at either 28 days or 1 year. Antibody responses to gpI and IE were similar when children were stratified by age (5 to 6 years, 7 to 11 years, 12 to 16 years). A short course of oral acyclovir for the treatment of varicella did not affect antibody responses to gpI or IE-62 (p170) in healthy children at 28 days and 1 year following varicella.
View details for Web of Science ID A1990DZ42500033
View details for PubMedID 2172288
View details for PubMedCentralID PMC268170
-
A PROSPECTIVE EVALUATION OF PRIMARY GENITAL HERPES-SIMPLEX VIRUS TYPE-2 INFECTIONS ACQUIRED DURING PREGNANCY
PEDIATRIC INFECTIOUS DISEASE JOURNAL
1990; 9 (7): 499-504
Abstract
In order to study the epidemiology of herpes simplex type 2 (HSV-2) infections during pregnancy, we used an enzyme immunoassay to detect type-specific antibodies to HSV-2 glycoprotein G in serial blood samples obtained from a cohort of 1891 pregnant women. Blood samples obtained at about 17 and 32 weeks of gestation and at the time of delivery were assessed for antibody to HSV-2 glycoprotein G in order to evaluate the prevalence of past infections with HSV-2 and the rate of acquisition of HSV-2 infection during pregnancy. Three hundred eleven pregnant women (16.5%) were found to have had past infections with HSV-2. Four of the 1580 women who were initially seronegative developed antibodies to HSV-2 during pregnancy. The annualized rate of acquisition of HSV-2 infection in pregnant women was 0.58%. Three of four women had asymptomatic primary infections; all of the women had preexisting HSV-1 immunity. None of the women or their infants experienced any adverse consequences of gestational herpes. Based upon our very limited number of observations to date, asymptomatic primary episodes occurring in women with previous HSV-1 immunity may be of less consequence to the fetus and neonate than symptomatic true primary HSV-2 infections.
View details for Web of Science ID A1990DP04600009
View details for PubMedID 2164656
-
THE LYMPHOCYTE-T RESPONSE TO VARICELLA-ZOSTER VIRAL-PROTEINS
4TH INTERNATIONAL CONF ON IMMUNOBIOLOGY AND PROPHYLAXIS OF HUMAN HERPESVIRUS INFECTIONS
PLENUM PRESS DIV PLENUM PUBLISHING CORP. 1990: 71–81
View details for Web of Science ID A1990BS15W00008
View details for PubMedID 1963047
-
NEONATAL ANTIBODY-DEPENDENT CELLULAR CYTO-TOXIC ANTIBODY-LEVELS ARE ASSOCIATED WITH THE CLINICAL PRESENTATION OF NEONATAL HERPES-SIMPLEX VIRUS-INFECTION
JOURNAL OF INFECTIOUS DISEASES
1989; 160 (5): 770-776
Abstract
The role of antiviral antibodies in protection against neonatal herpes simplex virus (HSV) infection remains controversial. The relationship between neonatal and maternal anti-HSV antibodies and disease presentation was analyzed in 47 babies. Of the neonates, 77% had localized and 23% had disseminated HSV infection. Antibody-dependent cellular cytotoxic (ADCC) antibodies were evaluated in comparison with HSV neutralizing antibodies. High maternal (greater than 1:10(4)) or neonatal (greater than 1:10(3)) anti-HSV ADCC antibody levels or high neonatal antiviral neutralizing levels (greater than 1:20) were independently associated with an absence of disseminated HSV infection. Cochran-Mantel-Haenszel analysis demonstrated that ADCC levels were associated with disease status (P less than .02) while controlling for the level of neutralizing antibody.
View details for Web of Science ID A1989AY21800005
View details for PubMedID 2553825
-
SEROLOGIC MIS-DIAGNOSIS OF CONGENITAL INFECTIONS
PEDIATRIC INFECTIOUS DISEASE JOURNAL
1989; 8 (8): 542-542
View details for Web of Science ID A1989AK78100023
View details for PubMedID 2549496
-
INVESTIGATION OF VARICELLA-ZOSTER VIRUS-INFECTION OF LYMPHOCYTES BY INSITU HYBRIDIZATION
JOURNAL OF VIROLOGY
1989; 63 (5): 2392-2395
Abstract
Peripheral blood mononuclear cells harboring viral gene sequences were detected during primary varicella-zoster virus (VZV) infection of the human host and the strain 2 guinea pig by in situ hybridization with a 3H-labeled VZV DNA probe. Activated T lymphocytes were permissive for VZV infection at low frequency in vitro.
View details for Web of Science ID A1989U126600072
View details for PubMedID 2539528
View details for PubMedCentralID PMC250665
-
ANTIVIRAL SUSCEPTIBILITIES OF HERPES-SIMPLEX VIRUS ISOLATES FROM INFANTS WITH RECURRENT MUCOCUTANEOUS LESIONS AFTER NEONATAL INFECTION
PEDIATRIC INFECTIOUS DISEASE JOURNAL
1989; 8 (4): 221-223
Abstract
Recurrent mucocutaneous lesions occur in many infants after completion of antiviral therapy of neonatal herpes simplex virus (HSV) infection. To determine whether these recurrences were caused by viruses that had become resistant to acyclovir or vidarabine, we tested the antiviral susceptibilities of 22 pretherapy and 32 posttherapy HSV isolates from 22 infants younger than 3 months of age. Sixteen had been treated with acyclovir and six with vidarabine. Antiviral susceptibilities were measured by an enzyme-linked immunosorbent assay and are expressed as the 50% inhibitory dose. All HSV isolates had a 50% inhibitory dose for acyclovir of less than 1.0 micrograms/ml. The mean vidarabine 50% inhibitory dose was 11.4 micrograms/ml for pretherapy isolates and 8.9 micrograms/ml for posttherapy isolates. Antiviral therapy did not select for recurrences with HSV resistant to acyclovir or vidarabine.
View details for Web of Science ID A1989U084200007
View details for PubMedID 2541398
-
LYMPHOCYTE-T CYTO-TOXICITY WITH NATURAL VARICELLA-ZOSTER VIRUS-INFECTION AND AFTER IMMUNIZATION WITH LIVE ATTENUATED VARICELLA VACCINE
JOURNAL OF IMMUNOLOGY
1989; 142 (2): 636-641
Abstract
Varicella-zoster virus (VZV) specific cytotoxicity was investigated during acute primary VZV infection, in naturally immune subjects and after vaccination with the live attenuated varicella vaccine by using T cell cultures (TCC) generated by stimulating PBMC with VZV Ag and autologous VZV-superinfected lymphoblastoid cell lines as targets. Lysis of VZV-infected lymphoblastoid cell lines was observed by TCC from acutely infected subjects, naturally immune subjects, and recipients of the varicella vaccine. VZV glycoprotein I induced cytotoxic T cells but killing was less efficient than killing by TCC stimulated with VZV Ag. The TCC were primarily CD4+ (mean 86.6%) T lymphocytes with 15.2% of the cells coexpressing Leu-19. TCC were predominantly restricted by HLA class II as demonstrated by lack of any blocking using class I mAb and blocking of 15 to 71% by L243, a mAb to class II. Unrestricted killing as measured by killing of K562 cells occurred in all TCC but was minimally greater than that observed against uninfected autologous targets. Phenotypes of PBMC during acute infection had an initial increase in CD4+ cells and an overall decrease in the percentage of circulating Leu-11+ (CD16). No enhanced K562 killing was demonstrated in PBMC from subjects with acute infection compared to subjects without infection. CD4+ CTL may function as an important primary host response in acute varicella. Immunization with live attenuated varicella vaccine induced VZV-specific, memory CTL responses comparable to those of naturally immune subjects. The demonstration of their persistence long after primary VZV infection may indicate a role for CTL in restriction of viral replication during episodes of VZV reactivation from latency.
View details for Web of Science ID A1989R647800039
View details for PubMedID 2536059
-
A CONCURRENT EPIDEMIC OF RESPIRATORY SYNCYTIAL VIRUS AND ECHOVIRUS-7 INFECTIONS IN AN INTENSIVE-CARE NURSERY
PEDIATRIC INFECTIOUS DISEASE JOURNAL
1989; 8 (1): 24-29
Abstract
We describe concurrent outbreaks of respiratory syncytial virus (RSV) and Echovirus 7 (Echo 7) infections in a neonatal intensive care unit, including infants who had dual infections. Seventy-three infants were identified as having RSV from January through June, 1984. During the same surveillance period Echo 7 was cultured from 20 infants, and 6 infants had concurrent RSV and Echo 7 and RSV were isolated, but not concurrently. This dual outbreak of RSV and Echo 7 infections persisted for months despite infection control measures. Control procedures were complicated by: (1) cases of RSV infection at less than 72 hours of age, which had not previously been reported and which led to the reintroduction of RSV into "clean" areas; (2) the lack of a rapid diagnostic test for enterovirus infection; (3) the number of infants who were asymptomatic with each infection; and (4) the logistical problems of handling a dual pathogen outbreak in a confined setting. These problems were compounded by the many risk factors associated with nosocomial infections found in neonatal intensive care settings such as prolonged hospitalizations, endotracheal or nasogastric tubes and contact with many ancillary care personnel.
View details for Web of Science ID A1989R833000007
View details for PubMedID 2922234
-
Genital herpes and the pregnant woman.
Current clinical topics in infectious diseases
1989; 10: 1-26
View details for PubMedID 2679690
-
IMMUNITY TO WHOLE VARICELLA-ZOSTER VIRUS-ANTIGEN AND GLYCOPROTEIN-I AND GLYCOPROTEIN-P170 - RELATION TO THE IMMUNIZING REGIMEN OF LIVE ATTENUATED VARICELLA VACCINE
JOURNAL OF INFECTIOUS DISEASES
1988; 158 (6): 1245-1252
Abstract
Humoral and cellular immune responses to whole varicella-zoster virus (VZV) antigen and the VZV proteins glycoprotein I (gpI) and nonglycosylated protein p170 were evaluated in healthy children and adults given lyophilized live-attenuated varicella vaccine. Children received one dose of vaccine containing 950 pfu, whereas adults received two doses of 2500 pfu. After one year, the antibody titers of adult vaccinees to whole VZV and to gpI were significantly higher than those of children. Antibody titers to whole VZV, gpI, and p170 were lower among both vaccine populations than titers in naturally immune individuals, but vaccinees who seroconverted initially retained detectable VZV antibodies. Using T lymphocyte proliferation to measure cellular immunity, we found the mean (+/- SE) transformation index to whole VZV antigen to be 4.1 +/- 0.96 in children tested at one year, a mean significantly lower than the mean of 12.7 +/- 3.39 in adults and 13.0 +/- 1.67 in naturally immune subjects. These observations suggest that the vaccine dose affects vaccine-induced immunity to VZV.
View details for Web of Science ID A1988R227100012
View details for PubMedID 2848901
-
CHANGING PRESENTATION OF HERPES-SIMPLEX VIRUS-INFECTION IN NEONATES
JOURNAL OF INFECTIOUS DISEASES
1988; 158 (1): 109-116
Abstract
We compared the clinical presentation of 95 newborns with herpes simplex virus (HSV) infection from 1973 through 1981 (first period) with data from 196 newborns evaluated from 1982 through 1987 (second period). There was a significant change in the presentation of infection in these infants. From the first to the second period, the frequency of disseminated disease decreased from 50.5% to 22.9%, whereas the frequency of skin, eye, and mouth (SEM) diseases increased from 17.9% to 43.4% (P less than .001). The frequency of infants with central nervous system (CNS) disease remained relatively unchanged--31.6% versus 33.7%. We also compared the demographic and clinical characteristics of the infants and their mothers. For neonates with CNS or disseminated infection, disease duration and frequency of prematurity were significantly decreased in the second period, as was the frequency of skin vesicles for newborns with SEM or disseminated infection. These changes are most likely the consequence of recognizing and treating SEM infection before its progression to more-severe disease.
View details for Web of Science ID A1988P126900014
View details for PubMedID 3392410
-
USE OF ROUTINE VIRAL CULTURES AT DELIVERY TO IDENTIFY NEONATES EXPOSED TO HERPES-SIMPLEX VIRUS
NEW ENGLAND JOURNAL OF MEDICINE
1988; 318 (14): 887-891
Abstract
We obtained specimens for viral culture from mothers, infants, or both at the time of 6904 deliveries, without regard to the mothers' history of genital herpes. Herpes simplex virus (HSV) was recovered in cultured specimens from 14 of the 6904 deliveries (0.20 percent); all 14 mothers were asymptomatic. All viral isolates were herpes simplex virus type 2 (HSV-2). Only 1 of the 14 women (7 percent) had a history of genital herpes, whereas 12 (86 percent) had serologic evidence of a previous infection with HSV-2. None of the infants born to these 12 women contracted neonatal herpes. However, one of the two infants born to women with serologic evidence of a primary HSV infection at the time of delivery contracted neonatal herpes. Our findings show that most infants at risk of exposure to HSV at delivery will not be identified if concern about asymptomatic shedding of virus is limited to women with a history of genital herpes infection. Most neonatal exposure to an asymptomatic maternal HSV infection at delivery is not predictable or preventable. Therefore, physicians caring for newborns need to consider neonatal herpes in the differential diagnosis when infants become ill during the first weeks of life, regardless of the presence or absence of identifiable risk factors for HSV infection.
View details for Web of Science ID A1988M802900004
View details for PubMedID 2832756
-
TYPE-SPECIFIC ANTIBODIES TO HERPES-SIMPLEX VIRUS TYPE-2 (HSV-2) GLYCOPROTEIN-G IN PREGNANT-WOMEN, INFANTS EXPOSED TO MATERNAL HSV-2 INFECTION AT DELIVERY, AND INFANTS WITH NEONATAL HERPES
JOURNAL OF INFECTIOUS DISEASES
1988; 157 (1): 164-171
Abstract
We used a murine monoclonal antibody to herpes simplex virus (HSV) type 2 (HSV-2) glycoprotein G (gG) to develop an enzyme immunoassay that detected HSV-2 type-specific antibodies in human sera. Antibodies to HSV-2 gG were detected in 98 (96%) of 102 sera from pregnant women with culture-proved HSV-2 infection. Sixty-five percent of the women had serological evidence of past HSV-2 infection by the Rawls index, based on titers of neutralizing antibody to HSV type 1 and HSV-2. Thirty (88%) of 34 infants exposed to maternal HSV infection at delivery had antibodies to HSV-2 gG and remained well. One infant exposed to primary maternal HSV-2 infection lacked antibodies to HSV-2 gG and developed neonatal HSV-2 infection. The mean +/- SD optical density by HSV-2 gG enzyme-linked immunosorbent assay for sera obtained from 17 infants within one week after onset of neonatal HSV-2 infection was 0.25 +/- 0.12, compared with 1.15 +/- 0.34 in cord blood sera from exposed infants who did not develop symptoms (P less than .0001 by t test).
View details for Web of Science ID A1988L370400023
View details for PubMedID 2826604
-
ANTIVIRAL DRUGS AND VACCINES FOR HERPES-SIMPLEX AND HERPES-ZOSTER - QUESTIONS AND ANSWERS
JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY
1988; 18 (1): 207-208
View details for Web of Science ID A1988L901200016
-
ANTIVIRAL TREATMENT OF HERPES-SIMPLEX INFECTION IN NEONATES AND PREGNANT-WOMEN
JOURNAL OF THE AMERICAN ACADEMY OF DERMATOLOGY
1988; 18 (1): 200-203
Abstract
Herpes simplex infections in neonates include (1) infections beginning in skin or mucous membranes, (2) infections of the central nervous system, and (3) disseminated herpes of the newborn. Early recognition of infections beginning in skin or mucous membranes is essential because 75% will disseminate internally if untreated. Skin lesions provide important diagnostic clues in herpes of the nervous system and disseminated herpes, but they often appear late and in only about 60% of infected neonates. Acyclovir and vidarabine are effective therapies but they must be administered early to prevent serious damage or death. Herpetic skin lesions in neonates may be confused with pyodermas. Direct immunofluorescence and cultures are reliable diagnostic tests. Congenital herpes may cause widespread skin involvement and multiple eye and nervous system diseases. The mother is the source of neonatal herpes in about two thirds of cases. Asymptomatic genital shedding of virus late in pregnancy does not accurately predict whether maternal cultures will be positive at the time of delivery. The risk of the infant acquiring neonatal herpes from a mother with recurrent herpes at birth is about 5%, but the risk is much higher if the mother has true primary genital infection.
View details for Web of Science ID A1988L901200014
View details for PubMedID 3276743
-
PHARMACOKINETICS OF ACYCLOVIR SUSPENSION IN INFANTS AND CHILDREN
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
1987; 31 (11): 1722-1726
Abstract
Eighteen children from 3 weeks to 6.9 years of age were given an oral acyclovir suspension for herpes simplex or varicella-zoster virus infections. Thirteen patients who were 6 months to 6.9 years old received 600 mg/m2 per dose, and three infants and two children less than 2 years old were given 300 mg/m2 per dose. The drug was given four times a day, except to one infant who was treated with three doses a day. Among the 13 children who received the 600-mg/m2 dose, the maximum concentration in plasma (Cmax) was 0.99 +/- 0.38 microgram/ml (mean +/- standard deviation), the time to maximum concentration (Tmax) was 3.0 +/- 0.86 h, the area under the curve (AUC) was 5.56 +/- 2.17 micrograms.h/ml, and the elimination half-life (t1/2) was 2.59 +/- 0.78 h. The three infants less than 2 months of age who received the 300-mg/m2 dose had a Cmax of 1.88 +/- 1.11 micrograms/ml, a Tmax of 4.10 +/- 0.48 h, an AUC of 6.54 +/- 4.32 micrograms.h/ml, and a t1/2 of 3.26 +/- 0.33 h. The acyclovir suspension was well tolerated by young children. No adverse effects requiring discontinuation of the drug occurred.
View details for Web of Science ID A1987K787700014
View details for PubMedID 2829714
View details for PubMedCentralID PMC175028
-
HUMORAL AND CELLULAR-IMMUNITY TO VARICELLA-ZOSTER VIRUS GLYCOPROTEIN GPI AND TO A NONGLYCOSYLATED PROTEIN, P170, IN THE STRAIN-2 GUINEA-PIG
JOURNAL OF GENERAL VIROLOGY
1987; 68: 2449-2454
Abstract
Strain 2 guinea-pigs were inoculated with infectious varicella-zoster virus (VZV) or with immunoaffinity-purified proteins of VZV. Monoclonal antibodies to the VZV gpI (90,000/58,000 complex) and to a non-glycosylated protein, p170, were used to prepare the polypeptide antigens. Humoral and cell-mediated immune responses to the infectious virus were compared with those elicited by the gpI and p170 proteins. Both VZV IgG antibody production and T lymphocyte proliferation to VZV were detected after immunization with infectious VZV and with VZV proteins. The antibody and T lymphocyte responses waned after protein immunization in comparison with the responses induced by infectious VZV but were detected again immediately after reimmunization with gpI or p170.
View details for Web of Science ID A1987K036200020
View details for PubMedID 2821181
-
PERINATAL VIRAL-INFECTIONS
EUROPEAN JOURNAL OF CLINICAL MICROBIOLOGY & INFECTIOUS DISEASES
1987; 6 (3): 245-261
Abstract
In comparison to older children and adults, neonates are immunologically incompetent. They are susceptible to infections caused by a variety of microorganisms, including bacteria, fungi and viruses. These infectious agents may be acquired by neonates either prenatally, during the intrapartum period or postnatally. The purpose of this review is to emphasize the potential impact of viral infections contracted by neonates at the time of delivery or within the neonatal period. The viruses reviewed include the herpes group of viruses (cytomegalovirus, herpes simplex viruses and varicella-zoster virus), type B hepatitis virus, human immunodeficiency virus, respiratory viruses, enteroviruses, rotavirus and human papilloma virus. For each virus the potential sources and incidence of the infection, the common manifestations of the illness, and possible means of prevention and therapy are discussed. Although infections caused by bacteria tend to be more clinically dramatic and more immediately life-threatening, it is emphasized that infections caused by viruses are common and associated with substantial long-term morbidity. Perinatal viral infections need to be recognized as early in life as possible so that their natural history can be more completely defined and any possible intervention made.
View details for Web of Science ID A1987H982000003
View details for PubMedID 3040392
-
GIANT-CELL PNEUMONIA CAUSED BY PARA-INFLUENZA TYPE-3 IN A PATIENT WITH ACUTE MYELOMONOCYTIC LEUKEMIA
ARCHIVES OF PATHOLOGY & LABORATORY MEDICINE
1987; 111 (6): 569-570
Abstract
A 4 1/2-year-old boy with acute myelomonocytic leukemia developed fever, neutropenia, and a prolonged respiratory illness while receiving maintenance chemotherapy. An open lung biopsy specimen demonstrated a giant cell pneumonia with intracytoplasmic and probable intranuclear viral inclusions of the paramyxovirus type. Serologic studies demonstrated convincing evidence of a parainfluenza type 3 infection. Although parainfluenza type 3-induced giant cell pneumonia has been reported in infants with the severe combined immunodeficiency syndrome, to our knowledge, this is the first reported case of this complication in a patient with leukemia.
View details for Web of Science ID A1987H468400022
View details for PubMedID 3034189
-
NEONATAL HERPES-SIMPLEX ENCEPHALITIS - CORRELATION OF CLINICAL AND CT FINDINGS
RADIOLOGY
1987; 162 (3): 813-819
Abstract
Review of 31 computed tomographic (CT) scans in 15 neonates with herpes simplex encephalitis (HSE) type 2 revealed the most characteristic early findings to be patchy and widespread areas of low attenuation, primarily in white matter, with minimal contrast material enhancement in a meningeal pattern. The low-attenuation lesions increased rapidly in size and prominence during the course of the disease. This was usually accompanied by increased attenuation of cortical gray matter that persisted for weeks to months. Atrophic changes appeared rapidly, being evident in the 3d week. Late findings consisted of very extensive, diffuse, low attenuation of white matter with cortical atrophy. Calcification assumed a variety of distributions, from punctate to an extensive gyral pattern. The cerebellum was involved in nine patients. Early CT findings were not good predictors of outcome, but later serial CT scans showing progression or stability of findings were more accurate in prognosis. CT serves primarily to confirm the diagnosis of neonatal HSE.
View details for Web of Science ID A1987G085800042
View details for PubMedID 3809499
-
LOW-RISK OF HERPES-SIMPLEX VIRUS-INFECTIONS IN NEONATES EXPOSED TO THE VIRUS AT THE TIME OF VAGINAL DELIVERY TO MOTHERS WITH RECURRENT GENITAL HERPES-SIMPLEX VIRUS-INFECTIONS
NEW ENGLAND JOURNAL OF MEDICINE
1987; 316 (5): 240-244
Abstract
We studied the risk of herpes simplex virus (HSV) infections in neonates exposed to HSV at the time of vaginal delivery to mothers with a history of recurrent genital HSV infections. None of 34 infants exposed to HSV type 2 acquired an HSV infection. On the basis of this sample, the 95 percent confidence limit for the theoretical maximum infection rate is 8 percent. Cord blood or blood obtained during the first two weeks of life was available from 33 of the 34 exposed, uninfected neonates. All 33 of the samples possessed demonstrable neutralizing antibody to HSV type 2, and 79 percent had titers above 1:20. These results were compared with those in a previously studied group of neonates with HSV infections; the latter infants were significantly less likely at the onset of symptoms to have demonstrable neutralizing antibody to HSV type 2 (P = 0.000148) or to have titers above 1:20 (P less than 0.00001). We conclude that given the low attack rate, empirical antiviral therapy is not warranted in all infants of mothers with recurrent genital HSV infection who are exposed to the virus in the birth canal. Our findings suggest that the presence and titer of neutralizing antibody to HSV contribute to the low attack rate.
View details for Web of Science ID A1987F737600003
View details for PubMedID 3025727
-
INTRAUTERINE HERPES-SIMPLEX VIRUS-INFECTIONS
JOURNAL OF PEDIATRICS
1987; 110 (1): 97-101
Abstract
Neonatal herpes simplex virus (HSV) infection is usually acquired at birth, although a few infants have had findings suggestive of intrauterine infection. We describe 13 babies who had clinical manifestations of intrauterine HSV infection, including skin lesions and scars at birth (12), chorioretinitis (eight), microcephaly (seven), hydranencephaly (five), and microphthalmia (two). All infants had combinations of these defects. Infection was proved by viral isolation in each case; all isolates were HSV-2. Two infants died during the first week of life; 10 of the surviving infants had severe neurologic sequelae, and one infant was blind. Four mothers experienced an apparent primary genital HSV infection, and one had recurrent infection, at varying times during gestation. The remaining women denied a history of symptoms of genital HSV infection. These findings indicate that intrauterine HSV infection can occur as a consequence of either primary or recurrent maternal infection and has severe consequences for the fetus.
View details for Web of Science ID A1987F570200021
View details for PubMedID 3794894
-
HUMORAL AND CELL-MEDIATED-IMMUNITY IN NEONATES WITH HERPES-SIMPLEX VIRUS-INFECTION
JOURNAL OF INFECTIOUS DISEASES
1987; 155 (1): 28-37
Abstract
Fifty-nine neonates with herpes simplex virus (HSV) infection were evaluated with use of assays for neutralizing antibody (NAb), lymphocyte transformation (LT), alpha interferon production, and virus-specific antibody (immunoblots). Infants with disseminated disease or onset in the first week of life were more likely to lack NAb. Patients treated with vidarabine were more likely than those treated with acyclovir to develop a fourfold rise in NAb titer. Infants with encephalitis showed a broader spectrum of IgG and IgM antibody reactivity against HSV proteins by immunoblotting than did those who had earlier onset of mucocutaneous illness. Only 10 of 33 infants had HSV-specific LT, compared with eight of eight adults with primary HSV. Neonates with positive LT were more likely to show a fourfold rise in NAb titer. In vitro alpha interferon production was diminished in infants, compared with values in adults.
View details for Web of Science ID A1987F315600003
View details for PubMedID 3025306
-
FAILURE OF ANTEPARTUM MATERNAL CULTURES TO PREDICT THE INFANTS RISK OF EXPOSURE TO HERPES-SIMPLEX VIRUS AT DELIVERY
NEW ENGLAND JOURNAL OF MEDICINE
1986; 315 (13): 796-800
Abstract
In 414 pregnant women with a history of recurrent genital herpes simplex infection, we studied the correlation between asymptomatic viral shedding in late pregnancy and at the time of delivery. Antepartum cultures for asymptomatic reactivation of herpes simplex virus were positive in 17 of the 414 women (4.1 percent). None of these women had positive cultures at the time of delivery. Cultures of specimens obtained at delivery from 5 of 354 asymptomatic mother-infant pairs (1.4 percent) were positive for asymptomatic excretion of herpes simplex virus. None of these women had had antepartum cultures that documented asymptomatic excretion of herpes simplex virus, despite the fact that culturing was repeatedly performed during the four weeks before delivery. Asymptomatic shedding of herpes simplex virus occurred with the same frequency at delivery, whether or not any episodes of symptomatic recurrence were noted during the pregnancy (1.4 vs. 1.3 percent). We conclude that antepartum maternal cultures do not predict the infant's risk of exposure to herpes simplex virus at delivery.
View details for Web of Science ID A1986E095200003
View details for PubMedID 3018565
-
EARLY IMMUNE-RESPONSE IN HEALTHY AND IMMUNOCOMPROMISED SUBJECTS WITH PRIMARY VARICELLA-ZOSTER VIRUS-INFECTION
JOURNAL OF INFECTIOUS DISEASES
1986; 154 (3): 422-429
Abstract
Events in pathogenesis and immunity during primary varicella-zoster virus (VZV) infection were examined in 64 healthy subjects and 21 immunocompromised patients. Activation of the interferon system and activation of circulating T lymphocytes were early immune responses that occurred during the incubation period in some healthy subjects. Elevated levels of 2-5A synthetase in peripheral blood mononuclear cells and detection of serum alpha interferon (IFN-alpha) and gamma interferon (IFN-gamma) were present in the majority of healthy subjects who had acute primary VZV infection. Expression of HLA-DR antigen occurred on circulating T lymphocytes from subjects with acute VZV infection. The early production of VZV-specific IgG or IgM antibodies did not correlate with the severity of the clinical infection, but the detection of T lymphocyte proliferation to VZV antigen within three days after the appearance of the varicella exanthem was associated with milder illness. The mean VZV-specific lymphocyte transformation for subjects with less than 100 lesions/m2 was 7.5 +/- 10.43 SD compared with 1.4 +/- 1.85 SD for those with greater than 400 lesions/m2 (P less than .05). Only one (7.7%) of 13 immunocompromised patients had early VZV-specific lymphocyte transformation compared with 19 (42%) of 45 healthy subjects (P less than .05). The rapid host response to primary VZV infection was associated with rapid termination of viremia in healthy subjects; VZV was isolated from only 11% of peripheral blood mononuclear cell samples cultured within 48 hr after the appearance of the exanthem.
View details for Web of Science ID A1986D760000006
View details for PubMedID 3016110
-
IMMUNITY TO VARICELLA-ZOSTER VIRAL GLYCOPROTEINS, GP-I (GP-90/58) AND GP-III (GP-118), AND TO A NONGLYCOSYLATED PROTEIN, P-170
JOURNAL OF IMMUNOLOGY
1986; 137 (4): 1346-1351
Abstract
Humoral and cellular immunity against two major glycoproteins (gp) of varicella-zoster virus (VZV), gp I (gp 90/58) and gp III (gp 118), and against a nonglycosylated phosphoprotein (p 170) was demonstrated in human subjects. Primary VZV infection was accompanied by the development of IgG to gp I (mean titer 1:200), gp III (mean titer 1:132), and p 170 (mean titer 1:331). Increased IgG antibody production to each of the VZV proteins occurred during recurrent VZV infection with mean titers to gp I of 1:29512, to gp III of 1:15848, and to p 170 of 1:15848. Persistent high titers to gp III (mean titer 1:891) and to p 170 (mean titer 1:2238) were observed in 75% and 88% of VZV-immune subjects, respectively. T lymphocytes which proliferated on stimulation with gp I, gp III, and p 170 developed with primary VZV infection. VZV-immune subjects had mean transformation indices of 4.2 +/- 0.70 SE to gp I, 4.7 +/- 1 SE to gp III, and 3 +/- 0.39 SE to p 170. Among individual subjects, humoral and cellular immunity was not always detected to all three of the VZV proteins. Resolution of primary VZV infection and maintenance of VZV latency did not require a host response to each of these major viral proteins.
View details for Web of Science ID A1986D523500041
View details for PubMedID 3016094
-
NEONATAL ASPERGILLOSIS - A CASE-REPORT AND REVIEW OF THE LITERATURE
CLINICAL PEDIATRICS
1986; 25 (8): 400-403
Abstract
Neonatal aspergillosis is a rare, usually overwhelming multisystem infection diagnosed postmortem. We present a neonate who had a brain abscess diagnosed by CT scan that was found at surgical exploration to contain aspergillus. Treatment included prolonged antifungal medication and several surgical interventions. The child has neurologic sequelae, including a seizure disorder and hemiplegia. There are no previously reported survivors of neonatal aspergillosis.
View details for Web of Science ID A1986D516900004
View details for PubMedID 3731668
-
INTRAUTERINE INFECTION WITH VARICELLA-ZOSTER VIRUS AFTER MATERNAL VARICELLA
NEW ENGLAND JOURNAL OF MEDICINE
1986; 314 (24): 1542-1546
Abstract
We investigated the consequences of maternal infection with varicella-zoster virus in a prospective study of 43 pregnancies complicated by varicella and 14 pregnancies complicated by herpes zoster. Nine of 43 pregnant women with varicella had associated morbidity--pneumonia (4 women), death (1), premature labor (4 of 42), premature delivery (2 of 42), and herpes zoster (1). Intrauterine varicella infection was identified on the basis of clinical evidence (anomalies characteristic of the congenital varicella syndrome, acute varicella at birth, or herpes zoster in infancy) or immunologic evidence (IgM antibody to varicella-zoster in the neonatal period, persistent IgG antibody to varicella-zoster at one to two years of age, or in vitro lymphocyte proliferation in response to varicella-zoster virus antigen). The congenital varicella syndrome occurred in 1 of 11 infants of women with first-trimester varicella. Immunologic evidence of intrauterine varicella infection was present in 7 of 33 infants tested; 4 of these infants were asymptomatic. According to clinical or immunologic criteria, 8 of 33 infants had evidence of intrauterine varicella infection. These observations show that varicella during pregnancy was associated with maternal morbidity and evidence of fetal infection, but that herpes zoster was not.
View details for Web of Science ID A1986C683600003
View details for PubMedID 3012334
-
VIDARABINE VERSUS ACYCLOVIR THERAPY OF NEONATAL HERPES-SIMPLEX VIRUS, HSV, INFECTION
INT PEDIATRIC RESEARCH FOUNDATION, INC. 1986: A323–A323
View details for Web of Science ID A1986A712001020
-
CHRONIC INFECTIOUS-MONONUCLEOSIS SYNDROME, PANCYTOPENIA, AND POLYCLONAL B-LYMPHOPROLIFERATION TERMINATING IN ACUTE LYMPHOBLASTIC-LEUKEMIA
AMERICAN JOURNAL OF PEDIATRIC HEMATOLOGY ONCOLOGY
1986; 8 (1): 18-27
Abstract
A 17-year-old previously healthy girl is reported who developed acute infectious mononucleosis followed by progressive ill health over 20 months, associated with pancytopenia and a polyclonal B-lymphoproliferation, terminating in acute lymphoblastic leukemia (ALL). Epstein-Barr virus (EBV) was recovered from the patient's nasopharyngeal secretions; serologic titers of antibodies to EBV-associated antigens were compatible with a chronic persistent EBV infection. Plasma interferon levels were markedly elevated. EBV-specific cell-mediated immunity, as well as Natural killer (NK) cell activity were markedly deficient. Other studies of cell-mediated immunity revealed notable abnormalities, including abnormalities in T-cell subset ratios, and a serum blocker of autologous mitogen-induced lymphoproliferation. Humoral (plasma)-mediated, but not cell-mediated, suppression of hemopoiesis was demonstrated using in vitro erythroid and myeloid colony culture techniques. Immunophenotyping of the patient's bone marrow cells preterminally was consistent with ALL. Autopsy revealed pathologic changes of ALL in marrow and multiple organs. We conclude that our patient developed an EBV-driven lymphoproliferative disorder, with associated defective cell-mediated immunity and hemopoiesis. Ultimately, the patient's documented polyclonal lymphoproliferative state was superimposed by acute lymphoblastic leukemia.
View details for Web of Science ID A1986C028900004
View details for PubMedID 3013037
-
HUMAN MONOCLONAL-ANTIBODIES NEUTRALIZING VARICELLA-ZOSTER VIRUS
JOURNAL OF INFECTIOUS DISEASES
1985; 152 (2): 280-285
Abstract
Hybridomas secreting human monoclonal antibodies to varicella-zoster virus were produced by fusing B cells of a patient recovering from acute varicella infection with a human-mouse cell line. Two hybrid lines have continued to secrete IgG1, one with kappa and the other with lambda chains, for at least 12 months. Each antibody neutralizes virus infectivity between 1-5 micrograms of partially purified immunoglobulin/ml, each shows a different pattern of immunofluorescent staining of virus-infected cells, and one identifies three viral proteins with molecular weights of 60,000, 95,000, and 97,000.
View details for Web of Science ID A1985AQZ7900006
View details for PubMedID 2993433
-
ANALYSIS OF VARICELLA-ZOSTER VIRUS WITH HUMAN MONOCLONAL-ANTIBODIES
SLACK INC. 1984: A513–A513
View details for Web of Science ID A1984SJ72502205
-
REASONS FOR THE ABSENCE OF A HISTORY OF RECURRENT GENITAL INFECTIONS IN MOTHERS OF NEONATES INFECTED WITH HERPES-SIMPLEX VIRUS
PEDIATRICS
1984; 73 (2): 188-193
Abstract
Thirty-one cases of neonatal herpes simplex (HSV) infection were evaluated to determine how often mothers of infected infants lacked a history of recurrent genital infections and the reasons for its absence. A history of recurrent genital infections was elicited from eight (26%) of the mothers. Nine (29%) of the mothers had primary infections; three of these were oral and six were genital. The mother was not the source of infection in three (9.6%) cases. In eleven (35%) cases, the mother had antibody to HSV but did not have a history or findings of primary or recurrent infection. Two of these mothers had positive cervical or vaginal cultures, but neither had genital lesions typical of HSV in the perinatal period. Two mothers had recurrent HSV infections documented later. The source of the HSV infection remained uncertain in 23% of cases including two in which only the father had a history of recurrent genital infection. When mothers with primary infections in the perinatal period were excluded, the HSV neutralization titers of the mothers of infected infants were similar to the titers of the mothers with recurrent genital infections whose infants were not infected. In contrast, the infected infants had titers fourfold lower than their mother's titer as well as fourfold lower than the 16 infants exposed to HSV who remained uninfected. This discrepancy suggests that the mothers may have had a rise in titer late in pregnancy or that placental transport of antibody was limited. Although 26% of the mothers of infected infants had recurrent genital infections, only three (9.6%) had an easily elicitable history.(ABSTRACT TRUNCATED AT 250 WORDS)
View details for Web of Science ID A1984SB81000013
View details for PubMedID 6538039
-
INVESTIGATION OF VARICELLA-ZOSTER VIRUS-INFECTED CELL-PROTEINS THAT ELICIT ANTIBODY-PRODUCTION DURING PRIMARY VARICELLA USING THE IMMUNE TRANSFER METHOD
JOURNAL OF GENERAL VIROLOGY
1984; 65 (DEC): 2141-2147
Abstract
The varicella-zoster virus-infected cell proteins (VZV-ICPs) against which IgG, IgM and IgA antibodies were made in the course of primary varicella-zoster virus (VZV) infection were analysed by the immune transfer method. IgG antibodies were made against one or more of 18 VZV-ICPs by patients with varicella. IgM antibodies were produced which reacted with 21 VZV-ICPs. The spectrum of IgG antibody production during the first week after the onset of infection was limited to an average of three VZV-ICPs while IgM antibodies which reacted with an average of seven VZV-ICPs were detectable in the acute phase of varicella. Equivalent VZV IgG or IgM antibody titres by radioimmunoassay did not correlate with a similar pattern of antibody specificity for VZV-ICPs by immune transfer. A detectable immune response to all VZV-ICPs was not required for the recovery of individual patients from primary VZV infection.
View details for Web of Science ID A1984TZ82400005
View details for PubMedID 6096492
-
COMPARISON OF VARICELLA ZOSTER ANTIBODY-TITERS IN PATIENTS GIVEN INTRAVENOUS IMMUNE SERUM GLOBULIN OR VARICELLA ZOSTER IMMUNE GLOBULIN
JOURNAL OF PEDIATRICS
1984; 105 (2): 200-205
Abstract
We compared the VZV IgG antibody titers after administration of varicella zoster immune globulin and serum immune globulin intravenously (IGIV) in VZV seronegative pediatric patients with cancer. Four patients received VZIG at standard doses; four received IGIV at 4 ml/kg every 4 weeks for four doses; and five received IGIV at 6 ml/kg every 6 weeks for two to four doses. VZV antibody titers were measured by radiommunoassay (RIA), enzyme-linked immunosorbent assay (ELISA), indirect fluorescent antibody assay (IFA), and neutralizing antibody assay. The mean peak and trough VZV titers by RIA were comparable in all three groups: 1:724 at 4 weeks after VZIG, 1:2048 at 4 weeks after 4 ml/kg IGIV, and 1:776 at 6 weeks after 6 ml/kg IGIV. The titers measured by ELISA, IFA, and neutralizing antibody were comparable after VZIG or IGIV. The VZV titers by RIA were maintained at greater than or equal to 1:1024 after subsequent doses of 4 ml/kg IGIV, and at greater than or equal to 1:256 after subsequent doses of 6 ml/kg IGIV. Adverse effects were rare. The VZV antibody titers assessed 4 to 6 weeks after IGIV administration were equivalent to the titers measured 4 weeks after administration of VZIG.
View details for Web of Science ID A1984TE14400004
View details for PubMedID 6086866
-
VARICELLA ZOSTER ANTIBODY-TITERS AFTER THE ADMINISTRATION OF INTRAVENOUS IMMUNE SERUM GLOBULIN OR VARICELLA ZOSTER IMMUNE GLOBULIN
AMERICAN JOURNAL OF MEDICINE
1984; 76 (3A): 124-127
Abstract
Varicella is a serious infection in the immunocompromised patient. Prophylaxis with varicella zoster immune globulin is known to decrease the incidence of severe varicella infection. The titers of antibody to varicella zoster virus were compared in patients who received either varicella zoster immune globulin or intravenous immune globulin, 4 ml or 6 ml/kg per dose. The titers of antibody to varicella zoster virus were comparable in each group.
View details for Web of Science ID A1984SL72400018
View details for PubMedID 6324585
-
VARICELLA ZOSTER VIRUS-ANTIBODY TITERS BEFORE AND AFTER ADMINISTRATION OF ZOSTER IMMUNE GLOBULIN TO NEONATES IN AN INTENSIVE-CARE NURSERY
JOURNAL OF PEDIATRICS
1983; 103 (1): 113-114
View details for Web of Science ID A1983QZ08300026
View details for PubMedID 6306191
-
SEROLOGICAL INVESTIGATION OF AN OUTBREAK OF SIMIAN VARICELLA IN ERYTHROCEBUS-PATAS MONKEYS
JOURNAL OF CLINICAL MICROBIOLOGY
1983; 18 (4): 901-904
Abstract
An epizootic of simian varicella occurring in a colony of Erythrocebus patas monkeys was studied serologically by using radioimmunoassay and neutralization tests against (i) a virus strain isolated from an animal that died during the epizootic, (ii) a simian varicella virus strain from an earlier outbreak of simian varicella-like disease at another facility, and (iii) human varicella-zoster virus. Serological tests detected more cases of infection among the animals exposed to virus during the epizootic than were evidenced by clinical findings; only 6 of the 26 animals with seroconversion developed a rash. Good correlation was seen between antibody responses demonstrated by radioimmunoassay and by the neutralization tests. Specificity of the radioimmunoassay was evidenced by the complete agreement with neutralization results for 17 animals which failed to show an antibody response over the course of the outbreak and were assumed not to have been infected. Thus radioimmunoassay is a reliable, rapid, and relatively economical method which could be used for serological screening of primates entering experimental colonies to identify those which might be potential sources of outbreaks through activation of latent simian varicella virus infection. Close correlation was seen between antibody responses to the virus strain from the current outbreak and the one from another epizootic, indicating that the two outbreaks were caused by antigenically similar viruses. Animals showing neutralizing antibody responses to the simian varicella viruses also showed responses to human varicella-zoster virus, which further substantiates the close antigenic relationship between human and simian varicella viruses.
View details for Web of Science ID A1983RJ11800028
View details for PubMedID 6313751
View details for PubMedCentralID PMC270927
-
SERUM IMMUNOGLOBULIN-A ANTIBODY TO VARICELLA-ZOSTER VIRUS IN SUBJECTS WITH PRIMARY VARICELLA AND HERPES-ZOSTER INFECTIONS AND IN IMMUNE SUBJECTS
JOURNAL OF CLINICAL MICROBIOLOGY
1983; 18 (5): 1146-1149
Abstract
Immunoglobulin A (IgA) antibodies to varicella-zoster virus (VZV) were measured in sera from subjects with acute varicella and herpes zoster, VZV-immune subjects remote from infection, and recipients of a live attenuated varicella vaccine, using a solid-phase radioimmunoassay. Primary infection with VZV was associated with early production of IgA antibodies. Among 36 subjects with varicella tested 1 to 5 days after onset, 22 had detectable IgA, and all of the negative sera were obtained before day 3 of the varicella exanthem. VZV IgA was detected in one of three sera obtained more than 60 days after onset of the illness. Four of five sera obtained from subjects within 1 week of the onset of herpes zoster had measurable levels of IgA. Between 1 and 4 weeks after onset of zoster, all 10 subjects tested had detectable IgA to VZV. VZV IgA was detected as late as 63 days after the onset of herpes zoster. Of 10 vaccine recipients, 5 developed VZV IgA which was detected as early as 4 weeks and persisted for as long as 16 weeks after vaccination. VZV IgA was not detected in sera from 42 children who had no detectable IgG antibody to VZV. VZV IgA was found on only 3 of 23 sera from adults who had varicella more than 20 years before.
View details for Web of Science ID A1983RN16000025
View details for PubMedID 6315766
View details for PubMedCentralID PMC272858
-
DETECTION OF TYPE-SPECIFIC ANTIBODY TO HERPES-SIMPLEX VIRUS TYPE-1 BY RADIOIMMUNOASSAY WITH HERPES-SIMPLEX VIRUS TYPE-1 GLYCOPROTEIN-C PURIFIED WITH MONOCLONAL-ANTIBODY
INFECTION AND IMMUNITY
1983; 40 (1): 184-189
Abstract
Herpes simplex virus type 1 (HSV-1) and HSV-2 specify at least four glycoproteins designated gA/gB, gC, gD, and gE. Previous studies have shown that gC produced by HSV-1 is antigenically distinct from the corresponding HSV-2 glycoprotein. With the exception of gC, the glycoproteins of both serotypes share antigenic sites. Standard serological assays fail to differentiate the antibody to the shared antigenic determinants from the type-specific antibody. In this paper, we describe a procedure for purifying gC from HSV-1-infected cell extracts with an immunoadsorbent prepared with an HCL monoclonal antibody. When used in a solid-phase radioimmunoassay, gC proved to be a type-specific antigen for quantitation of antibody to HSV-1. Among individuals who had no antibody to HSV at the onset of infection, all of those with primary HSV-1 infection developed antibody to gC. Subjects with primary HSV-2 infection failed to develop antibody reactive with gC of HSV-1 (P less than 0.01). Both immunoglobulin G and M antibodies against gC were detected in sera from subjects with either primary or recurrent HSV-1 infection. Higher antibody titers to gC were found in sera from individuals with recurrent infection than in sera from those with primary HSV-1 infection.
View details for Web of Science ID A1983QH54700026
View details for PubMedID 6832831
View details for PubMedCentralID PMC264834
-
IMMUNOLOGICAL EVIDENCE OF REINFECTION WITH VARICELLA-ZOSTER VIRUS
JOURNAL OF INFECTIOUS DISEASES
1983; 148 (2): 200-205
Abstract
Resistance to reinfection with varicella-zoster virus (VZV) was evaluated in immune adults who had household exposure to varicella. Sixty-four percent of 25 adults exposed to varicella had a fourfold or greater rise in IgG antibody to VZV or had a high initial IgG antibody titer to VZV that declined by fourfold. IgM antibody was detected in only 12% of 25 VZV-immune subjects. Seventy percent of 23 subjects exposed to varicella had IgA antibody to VZV compared with 13% of 23 subjects with antibody to VZV who had no recent exposure (P less than 0.001, chi 2 test). Enhanced cellular immunity was documented by an increase in lymphocyte transformation to VZV antigen from a mean +/- SE index of 7.8 +/- 1.30 to 15.3 +/- 2.56 (P = 0.01, paired t-test). The increase in immunity to VZV in many immune subjects exposed to VZV suggests the occurrence of subclinical reinfection.
View details for Web of Science ID A1983RG26600003
View details for PubMedID 6310001
-
FUSARIUM BRAIN-ABSCESS - CASE-REPORT
JOURNAL OF NEUROSURGERY
1983; 58 (4): 598-601
Abstract
The common soil fungus, Fusarium, is rarely pathogenic in man but occasionally causes serious disease, particularly in immunocompromised hosts. A case is reported of Fusarium brain abscess and meningitis occurring in a patient with chronic infectious mononucleosis syndrome and immunodeficiency. The patient died despite aspiration of the abscess and treatment with amphotericin B. This case demonstrates the importance of identifying the offending pathological organism through abscess aspiration in immunocompromised patients.
View details for Web of Science ID A1983QH80300022
View details for PubMedID 6827355
-
INTERFERON PROPHYLAXIS AGAINST SIMIAN VARICELLA IN ERYTHROCEBUS-PATAS MONKEYS
JOURNAL OF INFECTIOUS DISEASES
1983; 147 (1): 149-154
Abstract
Erythrocebus patas monkeys were given placebo or human leukocyte interferon (5 x 10(5) units/kg of body weight per day im) for five days during an epizootic of simian varicella. During the 14 days beginning with the first day of treatment, the attack rate for simian varicella was 14.3% (two of 14) among interferon recipients compared to 70% (nine of 13) among placebo recipients (P less than 0.025). Excluding animals with antibody to simian varicella when the study began, 18% (two) of 11 interferon recipients had symptoms of infection compared to 80% (nine) of 11 placebo recipients (P less than 0.025). The epizootic began in a room housing male animals. The incidence of infection in male placebo recipients was 100% (seven of seven) compared to 14% (one of seven) in male interferon recipients (P less than 0.01). The efficacy of interferon prophylaxis in the simian varicella model supports its continued evaluation for the management of human varicella in high-risk patients.
View details for Web of Science ID A1983QA17200020
View details for PubMedID 6296238
-
HUMAN-LEUKOCYTE INTERFERON FOR THE TREATMENT OF VARICELLA IN CHILDREN WITH CANCER
NEW ENGLAND JOURNAL OF MEDICINE
1982; 306 (13): 761-765
Abstract
Human leukocyte interferon was evaluated as a treatment for varicella in a randomized double-blind, placebo-controlled study carried out in two phases. A total of 44 children being treated for cancer were enrolled within 72 hours of the appearance of the exanthem. The mean number of days of new lesion formation was 3.8 +/- 1.89 (+/- S.D.) in the interferon recipients and 5.3 +/- 2.56 in the placebo recipients (P less than 0.05). Eighty-one per cent of the interferon recipients had had no new lesions for 24 hours by Day 7, as compared with 56 per cent of the placebo recipients (P less than 0.025). In the second, higher-dose phase of the study 92 per cent of the interferon recipients had had no new lesions for 24 hours by Day 6, as compared with 45 per cent of the placebo recipients (P less than 0.025). Three of 21 placebo recipients died of progressive varicella. Two of the 23 interferon recipients died two to three weeks after the onset of varicella; viral cultures were negative in one of these patients, and the second had recurrent viremia at the end of the treatment period. Among the survivors, treatment with interferon reduced the number of patients who had life-threatening dissemination (none of 21 vs. three of 18; P = 0.053). We conclude that interferon had an antiviral effect against varicella virus in immunocompromised patients.
View details for Web of Science ID A1982NG94400001
View details for PubMedID 6174864
-
CHEMOTHERAPY-INDUCED IMMUNOSUPPRESSION
ENVIRONMENTAL HEALTH PERSPECTIVES
1982; 43 (FEB): 21-25
Abstract
Chemotherapeutic agents are used widely in clinical medicine for the treatment of conditions where diminution of the host immune response is a goal. The clinical use of immunosuppression is indicated for immunologically mediated disease, lymphoproliferative diseases, and prevention of graft rejection. Five categories of agents are useful for these purposes; they are ionizing irradiation, corticosteroids, biological alkylating agents, antilymphocyte sera and antimetabolites. While the specific molecular action of many of these drugs is known, how they affect cellular events in immune responses is less clear. One of the unfortunate sequelae of chemotherapy induced immunosuppression is an increased susceptibility of the host to opportunistic pathogens or malignancies. Specific methods are described for monitoring the various parameters of both humoral and cellular immunity. Studies of immunologic function in lymphoma patients and cardiac transplant patients treated with immunosuppressive drugs have shown specific defects in cell mediated immunity to herpes viruses which may relate to their increased susceptibility to infection by these agents.
View details for Web of Science ID A1982NH02000004
View details for PubMedID 7037385
View details for PubMedCentralID PMC1568884
-
NEONATAL HERPES-SIMPLEX INFECTION IN THE ABSENCE OF MUCOCUTANEOUS LESIONS
JOURNAL OF PEDIATRICS
1982; 100 (5): 715-721
Abstract
Six infants with disseminated HSV had no mucocutaneous lesions at any time during the course of the illness. These infants presented with lethargy, poor feeding, apnea, acidosis, and hepatomegaly. The diagnosis of HSV was made by culturing the infant's oropharynx and blood, and the maternal cervix. Eight infants with HSV encephalitis had no skin, eye, or mucous membrane lesions. These infants presented with lethargy and low-grade fever, followed within 24 hours by the onset of focal partial motor seizures. The seizures were refractory to anticonvulsant therapy. The mean CSF white cell count was 131 cells/mm3;the glucose and protein concentrations were in the normal range. Brian biopsy was required for the early diagnosis of HSV encephalitis. These 14 cases presented 70% (14/20) of all infants with neonatal HSV diagnosed during the study period. HSV infection should be considered in infants with no mucocutaneous lesions who have signs usually associated with bacterial sepsis or who develop focal seizures during the first three weeks of life.
View details for Web of Science ID A1982NP21700008
View details for PubMedID 7069532
-
SPECIFIC CELL-MEDIATED-IMMUNITY AND INFECTIONS WITH HERPES VIRUSES IN CARDIAC TRANSPLANT RECIPIENTS
AMERICAN JOURNAL OF MEDICINE
1982; 73 (5): 679-687
Abstract
Immune responses and infections with herpes viruses were studied prospectively in 36 cardiac transplant recipients. Specific lymphocyte transformation and interferon production in response to viral antigens, viral culture results, antibody levels, responses to phytohemagglutinin, and T-cell numbers were determined. Responses to phytohemagglutinin and T-cell numbers were depressed for six to 12 weeks. Cytomegalovirus infection occurred in 100 percent of seropositive patients and in 62 percent of seronegative patients. Primary infection was more frequently symptomatic. Heart implantation from a seropositive patient wwas significantly correlated with subsequent infection in seronegative patients. Depression of transformation in response to cytomegalovirus correlated with prolonged shedding. Herpes simplex infection occurred in 95 percent of seropositive patients but decreased after 12 weeks. Asymptomatic shedding was rare, and primary infection did not occur. Return of transformation in response to herpes simplex was associated with decreased infection. Herpes zoster occurred in 22 percent during the first year, and transformation responses to varicella-zoster returned thereafter. Depression of interferon production in response to viruses did not correlate with infection as well as did lymphocyte transformation.
View details for Web of Science ID A1982PQ69700012
View details for PubMedID 6291387
-
ALPHA INTERFERON ADMINISTRATION TO INFANTS WITH CONGENITAL-RUBELLA
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
1982; 21 (2): 259-261
Abstract
Three infants with congenital rubella syndrome were given human leukocyte (alpha) interferon at doses of 2 x 10(5) to 7 X 10(5) U/kg per day for 10 days. A transient decrease in pharyngeal virus excretion was observed with treatment. No significant side effects were associated with the administration of human leukocyte interferon to these infants.
View details for Web of Science ID A1982NB67200012
View details for PubMedID 6176183
View details for PubMedCentralID PMC181869
-
THE VALIDITY OF REPORTING RESULTS OF CULTURES FOR HERPES-SIMPLEX VIRUS AFTER 4 DAYS
JOURNAL OF REPRODUCTIVE MEDICINE
1982; 27 (8): 447-448
View details for Web of Science ID A1982PG33500005
View details for PubMedID 6290657
-
ALPHA-INTERFERON IN SIMIAN AND HUMAN VARICELLA
UCLA SYMPOSIA ON MOLECULAR AND CELLULAR BIOLOGY
1982; 25: 393-397
View details for Web of Science ID A1982PM06400031
-
EFFECTS OF INTERFERON-ALPHA ON HUMAN WARTS
JOURNAL OF INTERFERON RESEARCH
1982; 2 (2): 235-243
Abstract
Two patients with extensive warts which were stable for two years or more were treated with human interferon-alpha to assess the ability of interferon to affect this benign tumor of viral etiology. Intramuscular administration of 96.6 and 135 million units over 12-15 weeks produced softening and decreased scaling of each patient's warts. Double blind, placebo-controlled intralesional injections resulted in progressive disappearance of interferon treated warts. A dose response relationship was shown in eight warts. The minimum effective dose was 1.2 x 10(6) units injected over 15.5 weeks.
View details for Web of Science ID A1982PG78800010
View details for PubMedID 7119508
-
THE EFFECT OF CHRONOLOGIC AGE ON THE SERUM CONCENTRATIONS OF AMIKACIN IN SICK TERM AND PREMATURE-INFANTS
JOURNAL OF PEDIATRICS
1981; 98 (4): 636-640
View details for Web of Science ID A1981LL47500031
View details for PubMedID 7205495
-
NEUTRALIZATION OF HERPES-SIMPLEX BY AMNIOTIC-FLUID
SLACK INC. 1981: A139–A139
View details for Web of Science ID A1981KY10800823
-
NEUTRALIZATION OF HERPES-SIMPLEX VIRUS BY ANTIBODY IN AMNIOTIC-FLUID
NATURE PUBLISHING GROUP. 1981: 608–
View details for Web of Science ID A1981LG15501010
-
SHORT-COURSE HUMAN-LEUKOCYTE INTERFERON IN TREATMENT OF HERPES-ZOSTER IN PATIENTS WITH CANCER
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
1981; 19 (1): 193-195
Abstract
Because of encouraging results when human leukocyte interferon was given for 5 to 7 days to treat early localized herpes zoster in patients with cancer, a small placebo-controlled, randomized, double-blind trial was set up involving only 48 h of therapy. In this trial, there was no effect on acute pain or disease progression in the primary dermatome. However, a modest but significant effect was noted in that distal cutaneous spread was diminished in the treated patients compared with the controls and the treated patients had diminished severity and duration of postherpetic neuralgia. No evidence of impairment in varicella-zoster-specific lymphocyte transformation was observed in interferon-treated patients.
View details for Web of Science ID A1981LA01400036
View details for PubMedID 6166245
View details for PubMedCentralID PMC181382
-
PREVENTION OF TRANSFUSION-ACQUIRED CYTOMEGALO-VIRUS INFECTIONS IN NEWBORN-INFANTS
JOURNAL OF PEDIATRICS
1981; 98 (2): 281-287
Abstract
Transfusion-acquired cytomegalovirus infections occurred in 13.5% of 74 infants of seronegative mothers who were exposed to one or more blood donors who had a CMV indirect hemagglutination titer of 1:8 or higher. None of 90 infants of seronegative mothers exposed only to donors with CMV IHA titers of less than 1:8 became infected. Ten of 41 (24%) infants of seronegative mothers who received more than 50 ml of packed red blood cells and who were exposed to at least one seropositive donor became infected. None of 23 infants of seronegative mothers who received this amount of blood but who were exposed only to seronegative donors became infected. Fatal or serious symptoms developed in 50% of the infected infants of seronegative mothers and in none of the 32 infected infants of seropositive mothers. Acquired CMV infections occurred in 15% of infants of seropositive mothers who were exposed to the red blood cells of seropositive donors and in 17.6% of infants of seropositive mothers exposed only to seronegative donors. Use of seronegative donors reduced the prevalence of excretion of CMV among hospitalized infants who were 4 weeks of age or older from 12.5 to 1.8% and eliminated acquired CMV infections in infants of seronegative mothers.
View details for Web of Science ID A1981LD52500029
View details for PubMedID 6257877
-
IMMUNOGLOBULIN-M AND IMMUNOGLOBLIN-G TO VARICELLA-ZOSTER VIRUS MEASURED BY SOLID-PHASE RADIOIMMUNOASSAY - ANTIBODY-RESPONSES TO VARICELLA AND HERPES-ZOSTER INFECTIONS
JOURNAL OF CLINICAL MICROBIOLOGY
1980; 12 (3): 367-374
Abstract
Both immunoglobulin M (IgM) and IgG antibodies to varicella-zoster virus (VZV) were detectable in a solid-phase radioimmunoassay with 125I-labeled goat antisera to human immunoglobulins. Primary infection with VZV was associated with early production of IgM and IgG antibodies and rapid development of lymphocyte transformation to VZV antigen. Among eight subjects with varicella tested 1 to 4 days after onset, seven patients had IgG and six patients had IgM antibodies; all patients had both IgG and IgM antibodies within 7 days. An IgM response was documented by radioimmunoassay in 18 of 26 patients with herpes zoster. VZV antibodies could be assayed by radioimmunoassay in unfractionated serum with commercial goat antisera to human immunoglobulins and commercial VZV antigen. VZV-specific IgG binding was present in all sera from 42 subjects with a VZB antibody titer of greater than or equal to 1:8 as determined by indirect immunofluorescence and cellular immunity to VZV as determined by lymphocyte transformation and who had had varicella at least 20 years before testing. The geometric mean titer was 1:6,309, and titers were greater than or equal to 1:16,384 in 20 subjects. Antibody was present as determined by radioimmunoassay in 14 samples negative by complement fixation and in five samples negative by complement fixation and immune adherence hemagglutination. No specific binding was observed in 21 sera from subjects who were not immune to VZV as determined by indirect immunofluorescence or lymphocyte transformation despite the presence of herpes simplex or cytomegalovirus antibody indicated by complement fixation in 15 sera. High titers of VZV IgM antibody were detected in unfractionated sera despite the presence of high titers of VZV IgG antibody. The VZV radioimmunoassay provided a sensitive and practical method for measuring VZV IgG and IgM antibodies.
View details for Web of Science ID A1980KH10300015
View details for PubMedID 6260833
View details for PubMedCentralID PMC273592
-
RELATIONSHIP OF ANTIBODY TO OUTCOME IN NEONATAL HERPES-SIMPLEX VIRUS-INFECTIONS
INFECTION AND IMMUNITY
1980; 29 (2): 532-538
Abstract
Neutralizing antibody titers to herpes simplex virus type 1 (HSV-1) and HSV-2 were measured at birth in normal infants and uninfected infants of mothers with genital HSV infections during pregnancy and at the onset of infection in 5 infants with mild infections and 11 infants with severe infections. Thirty-eight percent of premature and 29% of term infants had neutralization titers of <1:5. High titers ([unk]1:40) were found in 55% of infants of mothers with primary infections during pregnancy and in 76% of infants of mothers with recurrent infections. The mean titers to HSV-1 and -2 in 5 infected infants with mild infections were 1:56 and 1:65 at the time of onset of infection, whereas the mean titers in 11 infants with severe infections were 1:11 and 1:12. Six natally exposed infants who remained asymptomatic were also studied and had a mean titer to HSV-1 of 1:85 and to HSV-2 of 1:69. Therefore, infants with high titers of transplacentally derived antibody had a more favorable outcome than infants with lower titers. Ninety-five percent of the infants of mothers with recurrent infections had a Rawls index of more than 85, suggesting that the antibody response was to HSV-2. However, low levels of antibody with this type specificity failed to protect four infants from infection with HSV-2. Augmentation of the neutralization titer to HSV-2 by the amount of complement present in cord serum was less than twofold. The study suggests that the quantity of antibody derived transplacentally affects the outcome of infection after natal exposure to herpes simplex virus. Complete neutralization of virus by antibody may occur in some infants, and prolongation of the incubation period and modification of the infection may occur in others.
View details for Web of Science ID A1980KC83500037
View details for PubMedID 7216423
View details for PubMedCentralID PMC551151
-
CELLULAR AND HUMORAL IMMUNITY IN THE PATHOGENESIS OF RECURRENT HERPES VIRAL-INFECTIONS IN PATIENTS WITH LYMPHOMA
JOURNAL OF CLINICAL INVESTIGATION
1980; 65 (4): 869-878
Abstract
86 patients with lymphoma were evaluated prospectively for clinical and laboratory evidence of recurrent varicella-zoster, herpes simplex, and cytomegalovirus infections during the first 16 mo of treatment. Cellular immunity to the viral antigens was measured by in vitro lymphocyte transformation and interferon production. Antibody titers and nonspecific measures of cellular immunity, including T-cell quantitation and transformation to phytohemagglutinin, were also assessed. The patients treated with radiation and chemotherapy had the highest incidence of reactivation of each of the viruses (15-19%). Greater susceptibility to herpes viral reactivation in these patients correlated with suppression of cell-mediated immunity to the specific virus. In individual patients, suppression of cellular immunity to the specific herpes viral antigen preceded each episode of reactivation, but recurrent infection did not occur in all patients with diminished specific lymphocyte transformation. Absence of the response appears to be a necessary but not a sufficient condition for the recrudescence of latent infection. Better preservation of cellular immunity to herpes simplex antigen during treatment was associated with infrequent reactivation of herpes simplex. In 25 patients with acute herpes zoster, uncomplicated recovery from the infection was accompanied by the development of lymphocyte transformation and interferon production to varicella-zoster antigen. Quantitation of T-cell numbers and phytohemagglutinin transformation did not correlate with the presence of viral cellular immunity in treated patients. Responses returned while T-cell numbers were low, and the recovery of phytohemagglutinin transformation often preceded recovery of the responses to viral antigens. Although some patients had deficiencies in viral cellular immunity at diagnosis, the duration of the suppression of specific antiviral responses resulting from treatment appears to be the most important factor predisposing to the recurrence of herpes infections in lymphoma patients.
View details for Web of Science ID A1980JP40100013
View details for PubMedID 6244336
View details for PubMedCentralID PMC434474
-
PREVENTION OF TRANSFUSION-ASSOCIATED CYTOMEGALO-VIRUS INFECTIONS IN PREMATURE-INFANTS
AMER ASSOC BLOOD BANKS. 1980: 617–17
View details for Web of Science ID A1980KN83000085
-
HUMAN LEUKOCYTE INTERFERON IN TREATMENT OF VARICELLA IN CHILDREN WITH CANCER - PRELIMINARY CONTROLLED TRIAL
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
1978; 13 (4): 605-607
Abstract
Eighteen patients who developed varicella while being treated for malignancy received human leukocyte interferon in a randomized double-blind placebo-controlled trial. Complications of varicella occurred in six of nine placebo recipients, but in only two of nine interferon recipients. Interferon was tolerated without significant side effects.
View details for Web of Science ID A1978EW79300009
View details for PubMedID 352259
View details for PubMedCentralID PMC352295
-
SELECTIVE IMPAIRMENT OF LYMPHOCYTE-REACTIVITY TO VARICELLA-ZOSTER VIRUS-ANTIGEN AMONG UNTREATED PATIENTS WITH LYMPHOMA
JOURNAL OF INFECTIOUS DISEASES
1978; 137 (5): 531-540
Abstract
Herpes zoster is a frequent complication of lymphoreticular malignancy. In this study two assays of in vitro cellular immune response to varicella-zoster virus (VZV) antigen, lymphocyte transformation and interferon production, were performed in normal subjects with recent and remote VZV infection. The responses of patients with lymphoma were measured before treatment and during long-term remission and then compared with those of normal subjects. Despite levels of antibody to VZV that were equivalent to those in normal subjects, 44% of the untreated lymphoma patients showed a lower transformation response to VZV antigen than the normal patients. Production of interferon in response to VZV antigen was absent in 32% of the untreated patients. In contrast, lymphocyte responses in untreated patients to herpes simplex virus antigen were within the range observed in a normal population. Interferon production by lymphocytes in response to cytomegalovirus antigen was also lower among untreated lymphoma patients than among normal patients, but lymphocyte transformation was not. Twenty-two percent of lymphoma patients in long-term remission continued to have diminished cellular immune responses to VZV antigen. Observations in these patient populations and in normal subjects with acute herpes zoster suggest that deficiencies in in vitro lymphocyte responses may correlate with increased susceptibility to clinical infection with VZV.
View details for Web of Science ID A1978EZ28600004
View details for PubMedID 207782
-
CELL-MEDIATED-IMMUNITY TO CYTOMEGALOVIRUS-INFECTION IN NORMAL SUBJECTS AND CARDIAC TRANSPLANT PATIENTS
JOURNAL OF INFECTIOUS DISEASES
1978; 137 (5): 541-549
Abstract
Two assays of cell-mediated immunity, lymphocyte transformation and interferon production, were adapted to test for specific immunity to cytomegalovirus (CMV). Normal individuals seropositive for CMV had a mean transformation index of 7.9 in response to antigen of the Davis strain of CMV, whereas all of 14 seronegative normal individuals had transformation indexes of less than or equal to 3.0. Interferon production in seropositive and seronegative individuals was not statistically different. One to two months after CMV mononucleosis (after the termination of viruria), normal individuals had increased transformation indexes. Recipients of cardiac transplants within six months after transplant had normal levels of antibody to CMV; lymphocyte transformation and interferon production in these subjects were markedly decreased and returned to normal by three years and between one and three years after transplant, respectively. A syndrome of unexplained fever, hepatitis, pneumonitis, leukopenia, and atypical lymphocytes was common in a group of recipients with primary CMV infection. Shedding of virus was frequent in these symptomatic patients and in patients with repeat infection during the first three years after transplant. These assays appear to identify periods of immune deficits correlating with increased incidence of infection with CMV.
View details for Web of Science ID A1978EZ28600005
View details for PubMedID 207783
-
CELLULAR IMMUNITY AND HERPESVIRUS INFECTIONS IN CARDIAC-TRANSPLANT PATIENTS
NEW ENGLAND JOURNAL OF MEDICINE
1977; 296 (24): 1372-1377
Abstract
We observed severe infection with herpes simplex virus in cardiac-transplant patients despite their high serum antibody levels to this virus. Therefore, we sought to correlate clinical susceptibility to two herpesvirus (simplex and zoster) infections with specific cellular immunity, assessed by the transformation and interferon responses of peripheral blood mononuclear cells to heat-inactivated antigens. Transformation and interferon response to herps simplex virus was maximally depressed immediately after transplantation, the time when severe and prolonged infection with herps simplex virus occurred. Six months to six years after transplantation, both clinical susceptibility and cellular immunity to herpes simplex virus were normal. Herpes zoster infections were more frequent than normal at all times after cardiac transplantation; depressed or absent cellular responses to the varicella zoster virus paralleled that susceptibility. In these patients the risk of severe herpesvirus infections correlated with depressed cellular immune responses to the specific viral agent involved.
View details for Web of Science ID A1977DJ32700002
View details for PubMedID 193008
-
EFFECT OF LEUKOCYTE INTERFERON ON URINARY-EXCRETION OF CYTOMEGALOVIRUS BY INFANTS
JOURNAL OF INFECTIOUS DISEASES
1976; 133: A205-A210
Abstract
Five infants with symptomatic cytomegalovirus infections and high urinary titers of cytomegalovirus were treated with interferon in doses of 1.7-3.5 X 10(5) reference units/kg per day for seven to 14 days. Six courses of treatment were given. One of two infants treated with the largest dose of interferon had transient suppression of viruria; no suppression was noted during the other five courses of treatment. Adverse effects noted included a low rate of weight gain, a transient elevation of serum aspartate aminotransferase and fever. Further trials are needed to determine whether larger doses of a more purified preparation of interferon will eliminate viruria in infants with sytomegalovirus infection, but careful assessment of toxicity will be necessary in this population of patients.
View details for Web of Science ID A1976BY51400037
View details for PubMedID 180201