Sara Michie
Professor of Pathology (Research), Emerita
Honors & Awards
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Henry J. Kaiser Award for Excellence in Preclinical Teaching, Stanford Medical School (1998)
Current Research and Scholarly Interests
Our laboratory studies the molecular mechanisms that control the migration of lymphocytes into sites of autoimmune-mediated tissue damage, such as pancreatic islets in type 1 diabetes and salivary glands in Sjogrens syndrome. Our long-term goals include better understanding of the pathogenesis of autoimmune diseases, and development of novel diagnostic and therapeutic strategies.
2023-24 Courses
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Independent Studies (10)
- Directed Reading in Immunology
IMMUNOL 299 (Aut, Win, Spr, Sum) - Directed Reading in Pathology
PATH 299 (Win, Sum) - Early Clinical Experience in Immunology
IMMUNOL 280 (Aut, Win, Spr, Sum) - Early Clinical Experience in Pathology
PATH 280 (Win, Spr, Sum) - Graduate Research
IMMUNOL 399 (Aut, Sum) - Graduate Research
PATH 399 (Win, Spr, Sum) - Medical Scholars Research
PATH 370 (Win, Spr, Sum) - Teaching in Immunology
IMMUNOL 290 (Aut, Spr, Sum) - Undergraduate Research
IMMUNOL 199 (Aut, Win, Spr, Sum) - Undergraduate Research
PATH 199 (Win, Sum)
- Directed Reading in Immunology
All Publications
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LFA-1/ICAM-1 Adhesion Pathway Mediates the Homeostatic Migration of Lymphocytes from Peripheral Tissues into Lymph Nodes through Lymphatic Vessels.
Biomolecules
2023; 13 (8)
Abstract
Lymphocyte function-associated antigen-1 (LFA-1) and its endothelial ligand intercellular adhesion molecule-1 (ICAM-1) are important for the migration of lymphocytes from blood vessels into lymph nodes. However, it is largely unknown whether these molecules mediate the homeostatic migration of lymphocytes from peripheral tissues into lymph nodes through lymphatic vessels. In this study, we find that, in naive mice, ICAM-1 is expressed on the sinus endothelia of lymph nodes, but not on the lymphatic vessels of peripheral tissues. In in vivo lymphocyte migration assays, memory CD4+ T cells migrated to lymph nodes from peripheral tissues much more efficiently than from blood vessels, as compared to naive CD4+ T cells. Moreover, ICAM-1 deficiency in host mice significantly inhibited the migration of adoptively transferred wild-type donor lymphocytes from peripheral tissues, but not from blood vessels, into lymph nodes. The migration of LFA-1-deficient donor lymphocytes from peripheral tissues into the lymph nodes of wild-type host mice was also significantly reduced as compared to wild-type donor lymphocytes. Furthermore, the number of memory T cells in lymph nodes was significantly reduced in the absence of ICAM-1 or LFA-1. Thus, our study extends the functions of the LFA-1/ICAM-1 adhesion pathway, indicating its novel role in controlling the homeostatic migration of lymphocytes from peripheral tissues into lymph nodes and maintaining memory T cellularity in lymph nodes.
View details for DOI 10.3390/biom13081194
View details for PubMedID 37627259
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Expanding the spectrum of Kabuki syndrome with novel neuropathological, ocular and genetic findings in an autopsy case
OXFORD UNIV PRESS INC. 2020: 677
View details for Web of Science ID 000538796100099
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Inhibition of VEGF (Vascular Endothelial Growth Factor)-A or its Receptor Activity Suppresses Experimental Aneurysm Progression in the Aortic Elastase Infusion Model.
Arteriosclerosis, thrombosis, and vascular biology
2019: ATVBAHA119312497
Abstract
OBJECTIVE: We examined the pathogenic significance of VEGF (vascular endothelial growth factor)-A in experimental abdominal aortic aneurysms (AAAs) and the translational value of pharmacological VEGF-A or its receptor inhibition in aneurysm suppression. Approaches and Results: AAAs were created in male C57BL/6J mice via intra-aortic elastase infusion. Soluble VEGFR (VEGF receptor)-2 extracellular ligand-binding domain (delivered in Ad-VEGFR-2), anti-VEGF-A mAb, and sunitinib were used to sequester VEGF-A, neutralize VEGF-A, and inhibit receptor tyrosine kinase activity, respectively. Influences on AAAs were assessed using ultrasonography and histopathology. In vitro transwell migration and quantitative reverse transcription polymerase chain reaction assays were used to assess myeloid cell chemotaxis and mRNA expression, respectively. Abundant VEGF-A mRNA and VEGF-A-positive cells were present in aneurysmal aortae. Sequestration of VEGF-A by Ad-VEGFR-2 prevented AAA formation, with attenuation of medial elastolysis and smooth muscle depletion, mural angiogenesis and monocyte/macrophage infiltration. Treatment with anti-VEGF-A mAb prevented AAA formation without affecting further progression of established AAAs. Sunitinib therapy substantially mitigated both AAA formation and further progression of established AAAs, attenuated aneurysmal aortic MMP2 and MMP9 protein expression, inhibited inflammatory monocyte and neutrophil chemotaxis to VEGF-A, and reduced MMP2, MMP9, and VEGF-A mRNA expression in macrophages and smooth muscle cells in vitro. Additionally, sunitinib treatment reduced circulating monocytes in aneurysmal mice.CONCLUSIONS: VEGF-A and its receptors contribute to experimental AAA formation by suppressing mural angiogenesis, MMP and VEGF-A production, myeloid cell chemotaxis, and circulating monocytes. Pharmacological inhibition of receptor tyrosine kinases by sunitinib or related compounds may provide novel opportunities for clinical aneurysm suppression.
View details for DOI 10.1161/ATVBAHA.119.312497
View details for PubMedID 31294623
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Hypoxia-inducible factor 1 in clinical and experimental aortic aneurysm disease
JOURNAL OF VASCULAR SURGERY
2018; 68 (5): 1538-+
View details for DOI 10.1016/j.jvs.2017.09.030
View details for Web of Science ID 000447883100036
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Hypoxia-inducible factor 1 in clinical and experimental aortic aneurysm disease.
Journal of vascular surgery
2017
Abstract
OBJECTIVE: Mural angiogenesis and macrophage accumulation are two pathologic hallmarks of abdominal aortic aneurysm (AAA) disease. The heterodimeric transcription factor hypoxia-inducible factor 1 (HIF-1) is an essential regulator of angiogenesis and macrophage function. In this study, we investigated HIF-1 expression and activity in clinical and experimental AAA disease.METHODS: Human aortic samples were obtained from 24 AAA patients and six organ donors during open abdominal surgery. Experimental AAAs were created in 10-week-old male C57BL/6J mice by transient intra-aortic infusion of porcine pancreatic elastase (PPE). Expression of HIF-1alpha and its target gene messenger RNA (mRNA) levels were assessed in aneurysmal and control aortae. The HIF-1alpha inhibitors 2-methoxyestradiol and digoxin, the prolyl hydroxylase domain-containing protein (PHD) inhibitors cobalt chloride and JNJ-42041935, and the vehicle alone as control were administered daily to mice at varying time points beginning before or after PPE infusion. Influences on experimental AAA formation and progression were assessed by serial transabdominal ultrasound measurements of aortic diameter and histopathologic analysis at sacrifice.RESULTS: The mRNA levels for HIF-1alpha, vascular endothelial growth factor A, glucose transporter 1, and matrix metalloproteinase 2 were significantly increased in both human and experimental aneurysm tissue. Tissue immunostaining detected more HIF-1alpha protein in both human and experimental aneurysmal aortae compared with respective control aortae. Treatment with either HIF-1alpha inhibitor, beginning before or after PPE infusion, prevented enlargement of experimental aneurysms. Both HIF-1alpha inhibition regimens attenuated medial elastin degradation, smooth muscle cell depletion, and mural angiogenesis and the accumulation of macrophages, T cells, and B cells. Whereas mRNA levels for PHD1 and PHD2 were elevated in experimental aneurysmal aortae, pharmacologic inhibition of PHDs had limited effect on experimental aneurysm progression.CONCLUSIONS: Expression of HIF-1alpha and its target genes is increased in human and experimental AAAs. Treatment with HIF-1alpha inhibitors limits experimental AAA progression, with histologic evidence of attenuated mural leukocyte infiltration and angiogenesis. These findings underscore the potential significance of HIF-1alpha in aneurysm pathogenesis and as a target for pharmacologic suppression of AAA disease.
View details for PubMedID 29242064
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Human hepatic organoids for the analysis of human genetic diseases.
JCI insight
2017; 2 (17)
Abstract
We developed an in vitro model system where induced pluripotent stem cells (iPSCs) differentiate into 3-dimensional human hepatic organoids (HOs) through stages that resemble human liver during its embryonic development. The HOs consist of hepatocytes, and cholangiocytes, which are organized into epithelia that surround the lumina of bile duct-like structures. The organoids provide a potentially new model for liver regenerative processes, and were used to characterize the effect of different JAG1 mutations that cause: (a) Alagille syndrome (ALGS), a genetic disorder where NOTCH signaling pathway mutations impair bile duct formation, which has substantial variability in its associated clinical features; and (b) Tetralogy of Fallot (TOF), which is the most common form of a complex congenital heart disease, and is associated with several different heritable disorders. Our results demonstrate how an iPSC-based organoid system can be used with genome editing technologies to characterize the pathogenetic effect of human genetic disease-causing mutations.
View details for DOI 10.1172/jci.insight.94954
View details for PubMedID 28878125
View details for PubMedCentralID PMC5621886
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Human hepatic organoids for the analysis of human genetic diseases
JCI INSIGHT
2017; 2 (17)
View details for DOI 10.1172/jci.insight.94954
View details for Web of Science ID 000409549200016
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Angiotensin 1-7 Suppresses Experimental Abdominal Aortic Aneurysms
MOSBY-ELSEVIER. 2017: 198S–199S
View details for DOI 10.1016/j.jvs.2017.03.375
View details for Web of Science ID 000403108000359
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Inhibition or deletion of angiotensin II type 1 receptor suppresses elastase-induced experimental abdominal aortic aneurysms.
Journal of vascular surgery
2017
Abstract
Angiotensin (Ang) II type 1 receptor (AT1) activation is essential for the development of exogenous Ang II-induced abdominal aortic aneurysms (AAAs) in hyperlipidemic animals. Experimental data derived from this modeling system, however, provide limited insight into the role of endogenous Ang II in aneurysm pathogenesis. Consequently, the potential translational value of AT1 inhibition in clinical AAA disease management remains incompletely understood on the basis of the existing literature.AAAs were created in wild-type (WT) and AT1a knockout (KO) mice by intra-aortic infusion of porcine pancreatic elastase (PPE). WT mice were treated with the AT1 receptor antagonist telmisartan, 10 mg/kg/d in chow, or the peroxisome proliferator-activated receptor γ (PPARγ) antagonist GW9662, 3 mg/kg/d through oral gavage, beginning 1 week before or 3 days after PPE infusion. Influences on aneurysm progression as well as mechanistic insights into AT1-mediated pathogenic processes were determined using noninvasive ultrasound imaging, histopathology, aortic gene expression profiling, and flow cytometric analysis.After PPE infusion, aortic enlargement was almost completely abrogated in AT1a KO mice compared with WT mice. As defined by a ≥50% increase in aortic diameter, no PPE-infused, AT1a KO mouse actually developed an AAA. On histologic evaluation, medial smooth muscle cellularity and elastic lamellae were preserved in AT1a KO mice compared with WT mice, with marked attenuation of mural angiogenesis and leukocyte infiltration. In WT mice, telmisartan administration effectively suppressed aneurysm pathogenesis after PPE infusion as well, regardless of whether treatment was initiated before or after aneurysm creation or continued for a limited or extended time. Telmisartan treatment was associated with reduced messenger RNA levels for CCL5 and matrix metalloproteinases 2 and 9 in aneurysmal aortae, with no apparent effect on PPARγ-regulated gene expression. Administration of the PPARγ antagonist GW9662 failed to "rescue" the aneurysm phenotype in telmisartan-treated, PPE-infused WT mice. Neither effector T-cell differentiation nor regulatory T-cell cellularity was affected by telmisartan treatment status.Telmisartan effectively suppresses the progression of elastase-induced AAAs without apparent effect on PPARγ activation or T-cell differentiation. These findings reinforce the critical importance of endogenous AT1 activation in experimental AAA pathogenesis and reinforce the translational potential of AT1 inhibition in medical aneurysm disease management.
View details for DOI 10.1016/j.jvs.2016.12.110
View details for PubMedID 28434702
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A silk-based encapsulation platform for pancreatic islet transplantation improves islet function in vivo
JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE
2017; 11 (3): 887-895
Abstract
The success of pancreatic islet (PI) transplantation is challenged by PI functional damage during the peritransplantation period. A silk-based encapsulation platform including mesenchymal stromal cells (MSCs) was evaluated for islet cell delivery in vivo. Islet equivalents (IEQs) were transplanted into the epididymal fat pads of mice with streptozotocin-induced diabetes. Three PI combinations were tested: (A) co-encapsulated in silk with MSCs; (b) encapsulated in silk alone; or (c) pelleted. Blood glucose levels were monitored and intraperitoneal glucose tolerance test (IPGTT) was performed upon return to euglycaemia. Grafts were removed for histology and cytokine content analysis. Mice with PI grafts in silk showed a prompt return to euglycaemia. IPGTT was significantly improved with PI in silk with MSCs, compared to PI in silk alone or pelleted. Both Th1 and Th2 cytokines were increased in PI grafts in silk, but Th1 cytokines were decreased significantly with PI and MSC co-encapsulation. Histological analysis showed osteogenesis and chondrogenesis in the silk grafts containing MSCs. Future studies will evaluate MSC stability and function in vivo and improve silk biocompatibility for applications in islet transplantation. Copyright © 2015 John Wiley & Sons, Ltd.
View details for DOI 10.1002/term.1990
View details for Web of Science ID 000398046600029
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ICAM-1 Promotes Experimental Aortic Aneurysms Through Recruitment of Circulating Leukocytes
MOSBY-ELSEVIER. 2016: 62S–63S
View details for DOI 10.1016/j.jvs.2016.03.047
View details for Web of Science ID 000376230600098
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Diagnostic Dilemma in the Treatment of a Fatal Case of Bloody Diarrhea.
Journal of investigative medicine high impact case reports
2016; 4 (1): 2324709616638698-?
Abstract
Although diarrhea is the most commonly reported pediatric illness in the United States, mortality is usually a rare and unexpected event. We report the case of a healthy 13-month-old male that succumbed to a diarrheal illness of unclear etiology. Presenting signs included frequent nonbloody stools that progressed to frankly bloody stools over 72 hours. Associated symptoms included fever, tenesmus, relief with stool passage, and significant fatigue. On examination, the patient appeared tired and lay with legs curled toward his chest. The abdominal exam was remarkable for hypoactive bowel sounds, diffuse tenderness to palpation without guarding or rebound pain, and intermittent prolapse of rectal tissue. Abdominal plain films demonstrated a paucity of bowel gas, especially in the rectum; and ultrasound revealed thickening of bowel loops in the left lower quadrant. Abdominal computed tomography scan showed decreased enhancement of the mucosa of the rectosigmoid colon. The patient deteriorated rapidly with cardiorespiratory arrest occurring 48 hours after admission. Despite a protracted effort at cardiopulmonary resuscitation, perfusing heart rate or rhythm could not be reestablished. Autopsy revealed infarction and necrosis of the rectosigmoid colon with invasive gram-negative bacilli. Here we present his perplexing case, diagnostic evaluations, and suggest a unifying diagnosis.
View details for DOI 10.1177/2324709616638698
View details for PubMedID 27069937
View details for PubMedCentralID PMC4811016
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Does Metformin Suppress Aneurysmal Aortic Degeneration?
MOSBY-ELSEVIER. 2015: 524
View details for DOI 10.1016/j.jvs.2015.06.006
View details for Web of Science ID 000358431900046
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Humanized Thymidine Kinase-NOG Mice Can Be Used to Identify Drugs That Cause Animal-Specific Hepatotoxicity: A Case Study with Furosemide
JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS
2015; 354 (1): 73-78
Abstract
Interspecies differences have limited the predictive utility of toxicology studies performed using animal species. A drug that could be a safe and effective treatment in humans could cause toxicity in animals, preventing it from being used in humans. We investigated whether the use of thymidine kinase (TK)-NOG mice with humanized livers could prevent this unfortunate outcome (i.e., "rescue" a drug for use in humans). A high dose of furosemide is known to cause severe liver toxicity in mice, but it is a safe and effective treatment in humans. We demonstrate that administration of a high dose of furosemide (200 mg/kg i.p.) causes extensive hepatotoxicity in control mice but not in humanized TK-NOG mice. This interspecies difference results from a higher rate of production of the toxicity-causing metabolite by mouse liver. Comparison of their survival curves indicated that the humanized mice were more resistant than control mice to the hepatotoxicity caused by high doses of furosemide. In this test case, humanized TK-NOG mouse studies indicate that humans could be safely treated with a high dose of furosemide.
View details for DOI 10.1124/jpet,115.223393
View details for Web of Science ID 000357096900009
View details for PubMedID 25962391
View details for PubMedCentralID PMC4468429
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Immune Modulator FTY720 Suppresses Experimental Abdominal Aortic Aneurysms
MOSBY-ELSEVIER. 2015: 171S–172S
View details for DOI 10.1016/j.jvs.2015.04.326
View details for Web of Science ID 000361884200317
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Chimeric TK-NOG Mice: A Predictive Model for Cholestatic Human Liver Toxicity.
journal of pharmacology and experimental therapeutics
2015; 352 (2): 274-280
Abstract
Due to the substantial interspecies differences in drug metabolism and disposition, drug-induced liver injury (DILI) in humans is often not predicted by studies performed in animal species. For example, a drug (bosentan) used to treat pulmonary artery hypertension caused unexpected cholestatic liver toxicity in humans, which was not predicted by preclinical toxicology studies in multiple animal species. In this study, we demonstrate that NOG mice expressing a thymidine kinase transgene (TK-NOG) with humanized livers have a humanized profile of biliary excretion of a test (cefmetazole) drug, which was shown by an in situ perfusion study to result from interspecies differences in the rate of biliary transport and in liver retention of this drug. We also found that readily detectable cholestatic liver injury develops in TK-NOG mice with humanized livers after 1 week of treatment with bosentan (160, 32, or 6 mg/kg per day by mouth), whereas liver toxicity did not develop in control mice after 1 month of treatment. The laboratory and histologic features of bosentan-induced liver toxicity in humanized mice mirrored that of human subjects. Because DILI has become a significant public health problem, drug safety could be improved if preclinical toxicology studies were performed using humanized TK-NOG.
View details for DOI 10.1124/jpet.114.220798
View details for PubMedID 25424997
View details for PubMedCentralID PMC4293443
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A silk-based encapsulation platform for pancreatic islet transplantation improves islet function in vivo.
Journal of tissue engineering and regenerative medicine
2015
Abstract
The success of pancreatic islet (PI) transplantation is challenged by PI functional damage during the peritransplantation period. A silk-based encapsulation platform including mesenchymal stromal cells (MSCs) was evaluated for islet cell delivery in vivo. Islet equivalents (IEQs) were transplanted into the epididymal fat pads of mice with streptozotocin-induced diabetes. Three PI combinations were tested: (A) co-encapsulated in silk with MSCs; (b) encapsulated in silk alone; or (c) pelleted. Blood glucose levels were monitored and intraperitoneal glucose tolerance test (IPGTT) was performed upon return to euglycaemia. Grafts were removed for histology and cytokine content analysis. Mice with PI grafts in silk showed a prompt return to euglycaemia. IPGTT was significantly improved with PI in silk with MSCs, compared to PI in silk alone or pelleted. Both Th1 and Th2 cytokines were increased in PI grafts in silk, but Th1 cytokines were decreased significantly with PI and MSC co-encapsulation. Histological analysis showed osteogenesis and chondrogenesis in the silk grafts containing MSCs. Future studies will evaluate MSC stability and function in vivo and improve silk biocompatibility for applications in islet transplantation. Copyright © 2015 John Wiley & Sons, Ltd.
View details for DOI 10.1002/term.1990
View details for PubMedID 25619945
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VCAM-1/alpha 4 beta 1 Integrin Interaction Is Crucial for Prompt Recruitment of Immune T Cells into the Brain during the Early Stage of Reactivation of Chronic Infection with Toxoplasma gondii To Prevent Toxoplasmic Encephalitis
INFECTION AND IMMUNITY
2014; 82 (7): 2826-2839
Abstract
Reactivation of chronic infection with Toxoplasma gondii can cause life-threatening toxoplasmic encephalitis in immunocompromised individuals. We examined the role of VCAM-1/α4β1 integrin interaction in T cell recruitment to prevent reactivation of the infection in the brain. SCID mice were infected and treated with sulfadiazine to establish a chronic infection. VCAM-1 and ICAM-1 were the endothelial adhesion molecules detected on cerebral vessels of the infected SCID and wild-type animals. Immune T cells from infected wild-type mice were treated with anti-α4 integrin or control antibodies and transferred into infected SCID or nude mice, and the animals received the same antibody every other day. Three days later, sulfadiazine was discontinued to initiate reactivation of infection. Expression of mRNAs for CD3δ, CD4, CD8β, gamma interferon (IFN-γ), and inducible nitric oxide synthase (NOS2) (an effector molecule to inhibit T. gondii growth) and the numbers of CD4(+) and CD8(+) T cells in the brain were significantly less in mice treated with anti-α4 integrin antibody than in those treated with control antibody at 3 days after sulfadiazine discontinuation. At 6 days after sulfadiazine discontinuation, cerebral tachyzoite-specific SAG1 mRNA levels and numbers of inflammatory foci associated with tachyzoites were markedly greater in anti-α4 integrin antibody-treated than in control antibody-treated animals, even though IFN-γ and NOS2 mRNA levels were higher in the former than in the latter. These results indicate that VCAM-1/α4β1 integrin interaction is crucial for prompt recruitment of immune T cells and induction of IFN-γ-mediated protective immune responses during the early stage of reactivation of chronic T. gondii infection to control tachyzoite growth.
View details for DOI 10.1128/IAI.01494-13
View details for Web of Science ID 000338728400015
View details for PubMedID 24752515
View details for PubMedCentralID PMC4097612
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Propagermanium, a CCR2 Signaling Inhibitor, Suppresses Monocyte Mobilization and Migration in Experimental Aneurysms
MOSBY-ELSEVIER. 2014: 81S–82S
View details for DOI 10.1016/j.jvs.2014.03.183
View details for Web of Science ID 000337258400170
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CCR7 directs the recruitment of T cells into inflamed pancreatic islets of nonobese diabetic (NOD) mice.
Immunologic research
2014; 58 (2-3): 351-357
Abstract
Type 1 diabetes (T1D) is a T cell-mediated autoimmune disease characterized by the destruction of insulin-producing β cells in the pancreatic islets. The migration of T cells from blood vessels into pancreas is critical for the development of islet inflammation and β cell destruction in T1D. To define the roles of C-C chemokine receptor type 7 (CCR7) in recruitment of T cells into islets, we used laser capture microdissection to isolate tissue from inflamed islets of nonobese diabetic (NOD) mice and uninflamed islets of BALB/c and young NOD mice. RT-PCR analyses detected mRNAs for CCR7 and its chemokine ligands CCL19 (ELC; MIP-3β) and CCL21 (SLC) in captures from inflamed, but not from uninflamed, islets. Immunohistology studies revealed that high endothelial venules in inflamed islets co-express CCL21 protein and MAdCAM-1 (an adhesion molecule that recruits lymphocytes into islets). Desensitization of lymphocyte CCR7 blocked about 75 % of T cell migration from the bloodstream into inflamed islets, but had no effect on B cell migration into islets. These results indicate that CCR7 and its ligands are important in the recruitment of T cells into inflamed islets and thus in the pathogenesis of T1D.
View details for DOI 10.1007/s12026-014-8500-9
View details for PubMedID 24687731
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Fialuridine Induces Acute Liver Failure in Chimeric TK-NOG Mice: A Model for Detecting Hepatic Drug Toxicity Prior to Human Testing.
PLoS medicine
2014; 11 (4)
View details for DOI 10.1371/journal.pmed.1001628
View details for PubMedID 24736310
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Fialuridine induces acute liver failure in chimeric TK-NOG mice: a model for detecting hepatic drug toxicity prior to human testing.
PLoS medicine
2014; 11 (4)
Abstract
Seven of 15 clinical trial participants treated with a nucleoside analogue (fialuridine [FIAU]) developed acute liver failure. Five treated participants died, and two required a liver transplant. Preclinical toxicology studies in mice, rats, dogs, and primates did not provide any indication that FIAU would be hepatotoxic in humans. Therefore, we investigated whether FIAU-induced liver toxicity could be detected in chimeric TK-NOG mice with humanized livers.Control and chimeric TK-NOG mice with humanized livers were treated orally with FIAU 400, 100, 25, or 2.5 mg/kg/d. The response to drug treatment was evaluated by measuring plasma lactate and liver enzymes, by assessing liver histology, and by electron microscopy. After treatment with FIAU 400 mg/kg/d for 4 d, chimeric mice developed clinical and serologic evidence of liver failure and lactic acidosis. Analysis of liver tissue revealed steatosis in regions with human, but not mouse, hepatocytes. Electron micrographs revealed lipid and mitochondrial abnormalities in the human hepatocytes in FIAU-treated chimeric mice. Dose-dependent liver toxicity was detected in chimeric mice treated with FIAU 100, 25, or 2.5 mg/kg/d for 14 d. Liver toxicity did not develop in control mice that were treated with the same FIAU doses for 14 d. In contrast, treatment with another nucleotide analogue (sofosbuvir 440 or 44 mg/kg/d po) for 14 d, which did not cause liver toxicity in human trial participants, did not cause liver toxicity in mice with humanized livers.FIAU-induced liver toxicity could be readily detected using chimeric TK-NOG mice with humanized livers, even when the mice were treated with a FIAU dose that was only 10-fold above the dose used in human participants. The clinical features, laboratory abnormalities, liver histology, and ultra-structural changes observed in FIAU-treated chimeric mice mirrored those of FIAU-treated human participants. The use of chimeric mice in preclinical toxicology studies could improve the safety of candidate medications selected for testing in human participants. Please see later in the article for the Editors' Summary.
View details for DOI 10.1371/journal.pmed.1001628
View details for PubMedID 24736310
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Enabling Autologous Human Liver Regeneration With Differentiated Adipocyte Stem Cells
CELL TRANSPLANTATION
2014; 23 (12): 1573-1584
Abstract
We developed a novel method for differentiating adipocyte-derived stem cells (ASCs) into hepatocyte-like cells (iHeps). ASCs are cultured as spherical cellular aggregates, and are then induced by culture in chemically defined media for a short time period to differentiate into spherical-culture iHeps (SCi-Heps). SCi-Heps have many of the in vitro functional properties of mature hepatocytes, and they can stably reconstitute functioning human liver in vivo in a murine model system, and implantation studies demonstrate that SCi-Heps have a very low malignant potential. All human liver regenerative procedures, including ultrasound-guided direct liver implantation, are scalable and appropriate for human clinical use. These methods can be used to achieve the major promise of regenerative medicine; it may now be possible to regenerate human liver using autologous stem cells obtained from a readily accessible tissue.
View details for DOI 10.3727/096368913X673432
View details for PubMedID 24148223
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Protein polymer hydrogels: Effects of endotoxin on biocompatibility.
Journal of biomaterials applications
2013; 28 (3): 395-406
Abstract
Protein polymer-based hydrogels have shown potential for tissue engineering applications, but require biocompatibility testing for in vivo use. Enzymatically crosslinked protein polymer-based hydrogels were tested in vitro and in vivo to evaluate their biocompatibility. Endotoxins present in the hydrogel were removed by Trition X-114 phase separation. The reduction of endotoxins decreased TNF-α production by a macrophage cell line in vitro; however, significant inflammatory response was still present compared to collagen control gels. A branched PEG molecule and dexamethasone were added to the hydrogel to reduce the response. In vitro testing showed a decrease in the TNF-α levels with the addition of dexamethasone. In vivo implantations into the epididymal fat pad of C57/BL6 mice, however, indicated a decreased inflammatory mediated immune response with a hydrogel treated with both PEGylation and endotoxin reduction. This study demonstrates the importance of endotoxin testing and removal in determining the biocompatibility of biomaterials.
View details for DOI 10.1177/0885328212454555
View details for PubMedID 22832218
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VCAM-1/alpha 4 beta 1 integrin interaction is important for T cell recruitment to prevent reactivation of chronic infection with Toxoplasma gondii in the brain
AMER ASSOC IMMUNOLOGISTS. 2013
View details for Web of Science ID 000322987104001
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Text-mining applied to autoimmune disease research: the Sjogren's syndrome knowledge base
BMC MUSCULOSKELETAL DISORDERS
2012; 13
Abstract
Sjögren's syndrome is a tissue-specific autoimmune disease that affects exocrine tissues, especially salivary glands and lacrimal glands. Despite a large body of evidence gathered over the past 60 years, significant gaps still exist in our understanding of Sjögren's syndrome. The goal of this study was to develop a database that collects and organizes gene and protein expression data from the existing literature for comparative analysis with future gene expression and proteomic studies of Sjögren's syndrome.To catalog the existing knowledge in the field, we used text mining to generate the Sjögren's Syndrome Knowledge Base (SSKB) of published gene/protein data, which were extracted from PubMed using text mining of over 7,700 abstracts and listing approximately 500 potential genes/proteins. The raw data were manually evaluated to remove duplicates and false-positives and assign gene names. The data base was manually curated to 477 entries, including 377 potential functional genes, which were used for enrichment and pathway analysis using gene ontology and KEGG pathway analysis.The Sjögren's syndrome knowledge base ( http://sskb.umn.edu) can form the foundation for an informed search of existing knowledge in the field as new potential therapeutic targets are identified by conventional or high throughput experimental techniques.
View details for DOI 10.1186/1471-2474-13-119
View details for Web of Science ID 000310889200002
View details for PubMedID 22759918
View details for PubMedCentralID PMC3495204
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Systems analysis of primary Sjogren's syndrome pathogenesis in salivary glands identifies shared pathways in human and a mouse model
ARTHRITIS RESEARCH & THERAPY
2012; 14 (6)
Abstract
Primary Sjögren's syndrome (pSS) is a chronic autoimmune disease with complex etiopathogenesis. Despite extensive studies to understand the disease process utilizing human and mouse models, the intersection between these species remains elusive. To address this gap, we utilized a novel systems biology approach to identify disease-related gene modules and signaling pathways that overlap between humans and mice.Parotid gland tissues were harvested from 24 pSS and 16 non-pSS sicca patients and 25 controls. For mouse studies, salivary glands were harvested from C57BL/6.NOD-Aec1Aec2 mice at various times during development of pSS-like disease. RNA was analyzed with Affymetrix HG U133+2.0 arrays for human samples and with MOE430+2.0 arrays for mouse samples. The images were processed with Affymetrix software. Weighted-gene co-expression network analysis was used to identify disease-related and functional pathways.Nineteen co-expression modules were identified in human parotid tissue, of which four were significantly upregulated and three were downregulated in pSS patients compared with non-pSS sicca patients and controls. Notably, one of the human disease-related modules was highly preserved in the mouse model, and was enriched with genes involved in immune and inflammatory responses. Further comparison between these two species led to the identification of genes associated with leukocyte recruitment and germinal center formation.Our systems biology analysis of genome-wide expression data from salivary gland tissue of pSS patients and from a pSS mouse model identified common dysregulated biological pathways and molecular targets underlying critical molecular alterations in pSS pathogenesis.
View details for DOI 10.1186/ar4081
View details for Web of Science ID 000315192300014
View details for PubMedCentralID PMC3674589
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Systems analysis of primary Sjögren's syndrome pathogenesis in salivary glands identifies shared pathways in human and a mouse model.
Arthritis research & therapy
2012; 14 (6): R238-?
Abstract
Primary Sjögren's syndrome (pSS) is a chronic autoimmune disease with complex etiopathogenesis. Despite extensive studies to understand the disease process utilizing human and mouse models, the intersection between these species remains elusive. To address this gap, we utilized a novel systems biology approach to identify disease-related gene modules and signaling pathways that overlap between humans and mice.Parotid gland tissues were harvested from 24 pSS and 16 non-pSS sicca patients and 25 controls. For mouse studies, salivary glands were harvested from C57BL/6.NOD-Aec1Aec2 mice at various times during development of pSS-like disease. RNA was analyzed with Affymetrix HG U133+2.0 arrays for human samples and with MOE430+2.0 arrays for mouse samples. The images were processed with Affymetrix software. Weighted-gene co-expression network analysis was used to identify disease-related and functional pathways.Nineteen co-expression modules were identified in human parotid tissue, of which four were significantly upregulated and three were downregulated in pSS patients compared with non-pSS sicca patients and controls. Notably, one of the human disease-related modules was highly preserved in the mouse model, and was enriched with genes involved in immune and inflammatory responses. Further comparison between these two species led to the identification of genes associated with leukocyte recruitment and germinal center formation.Our systems biology analysis of genome-wide expression data from salivary gland tissue of pSS patients and from a pSS mouse model identified common dysregulated biological pathways and molecular targets underlying critical molecular alterations in pSS pathogenesis.
View details for DOI 10.1186/ar4081
View details for PubMedID 23116360
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The immunoglobulin heavy chain gene 3 ' enhancers induce Bcl2 deregulation and lymphomagenesis in murine B cells
LEUKEMIA
2011; 25 (9): 1484-1493
Abstract
Human follicular B-cell lymphoma is associated with the t(14;18) chromosomal translocation that juxtaposes the Bcl2 proto-oncogene with the immunoglobulin heavy chain (Igh) locus, resulting in the deregulated expression of Bcl2. Our previous studies have shown that the Igh 3' enhancers deregulate the Bcl2 expression in vitro. However, the effects of the Igh 3' enhancer elements on Bcl2 expression in vivo are not known. To investigate the role of the Igh 3' enhancers in Bcl2 deregulation, we used gene targeting to generate knock-in mice in which four DNase I-hypersensitive regions from the murine Igh 3' region were integrated 3' of the Bcl2 locus. Increased levels of Bcl2 mRNA and protein were observed in the B cells of Igh-3'E-bcl2 mice. B cells from Igh-3'E-bcl2 mice showed an extended survival in vitro compared with B cells from wild-type (Wt) mice. The Bcl2 promoter shift from P1 (the 5' promoter) to P2 (the 3' promoter) was observed in B cells from Igh-3'E-bcl2 mice, similar to human t(14;18) lymphomas. The IgH-3'E-bcl2 mice developed monoclonal B-cell follicular lymphomas, which were slowly progressive. These studies show that the Igh 3' enhancers have an important role in the deregulation of Bcl2 and B-cell lymphomagenesis in vivo.
View details for DOI 10.1038/leu.2011.115
View details for Web of Science ID 000294665400014
View details for PubMedID 21606958
View details for PubMedCentralID PMC3162065
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alpha(4)beta(7) integrin/MAdCAM-1 adhesion pathway is crucial for B cell migration into pancreatic lymph nodes in nonobese diabetic mice
JOURNAL OF AUTOIMMUNITY
2010; 35 (2): 124-129
Abstract
Although B cells are crucial antigen-presenting cells in the initiation of T cell autoimmunity to islet beta cell autoantigens in type 1 diabetes (T1D), adhesion molecules that control migration of B cells into pancreatic lymph nodes (PanLN) in the nonobese diabetic (NOD) mouse model of human T1D have not been defined. In this study, we found that B cells from PanLN of 3-4-week-old female NOD mice expressed high levels of alpha(4) integrin and LFA-1 and intermediate levels of beta(7) integrin; half of B cells were L-selectin(high). In short-term in vivo lymphocyte migration assays, B cells migrated from the bloodstream into PanLN more efficiently than into peripheral LNs. Moreover, antibodies to mucosal addressin cell adhesion molecule 1 (MAdCAM-1) and alpha(4)beta(7) integrin inhibited >90% of B cell migration into PanLN. In contrast, antibodies to peripheral node addressin, L-selectin or LFA-1 partially inhibited B cell migration into PanLN. Furthermore, one intraperitoneal injection of anti-MAdCAM-1 antibody into 3-week-old NOD mice significantly inhibited entry of B cells into PanLN for at least 2 weeks. Taken together, these results indicate that the alpha(4)beta(7) integrin/MAdCAM-1 adhesion pathway plays a predominant role in migration of B cells into PanLN in NOD mice. Thus, specific blockage of alpha(4)beta(7) integrin/MAdCAM-1 adhesion pathway-mediated B cell migration may be a potential treatment for T1D.
View details for DOI 10.1016/j.jaut.2010.04.002
View details for Web of Science ID 000281986100003
View details for PubMedID 20488663
View details for PubMedCentralID PMC2926266
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Removal of Toxoplasma gondii cysts from the brain by perforin-mediated activity of CD8+T cells
AMER ASSOC IMMUNOLOGISTS. 2010
View details for Web of Science ID 000209758300208
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Removal of Toxoplasma gondii Cysts from the Brain by Perforin-Mediated Activity of CD8(+) T Cells
AMERICAN JOURNAL OF PATHOLOGY
2010; 176 (4): 1607-1613
Abstract
Chronic infection with Toxoplasma gondii is one of the most common parasitic infections in humans. Formation of tissue cysts is the basis of persistence of the parasite in infected hosts, and this cyst stage has generally been regarded as untouchable. Here we provide the first evidence that the immune system can eliminate T. gondii cysts from the brains of infected hosts when immune T cells are transferred into infected immunodeficient animals that have already developed large numbers of cysts. This T cell-mediated immune process was associated with accumulation of microglia and macrophages around tissue cysts. CD8(+) immune T cells possess a potent activity to remove the cysts. The initiation of this process by CD8(+) T cells does not require their production of interferon-gamma, the major mediator to prevent proliferation of tachyzoites during acute infection, but does require perforin. These results suggest that CD8(+) T cells induce elimination of T. gondii cysts through their perforin-mediated cytotoxic activity. Our findings provide a new mechanism of the immune system to fight against chronic infection with T. gondii and suggest a possibility of developing a novel vaccine to eliminate cysts from patients with chronic infection and to prevent the establishment of chronic infection after a newly acquired infection.
View details for DOI 10.2353/ajpath.2010.090825
View details for Web of Science ID 000276471500008
View details for PubMedID 20167872
View details for PubMedCentralID PMC2843452
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PPAR-delta senses and orchestrates clearance of apoptotic cells to promote tolerance
NATURE MEDICINE
2009; 15 (11): 1266-U59
Abstract
Macrophages rapidly engulf apoptotic cells to limit the release of noxious cellular contents and to restrict autoimmune responses against self antigens. Although factors participating in recognition and engulfment of apoptotic cells have been identified, the transcriptional basis for the sensing and the silent disposal of apoptotic cells is unknown. Here we show that peroxisome proliferator-activated receptor-delta (PPAR-delta) is induced when macrophages engulf apoptotic cells and functions as a transcriptional sensor of dying cells. Genetic deletion of PPAR-delta decreases expression of opsonins such as complement component-1qb (C1qb), resulting in impairment of apoptotic cell clearance and reduction in anti-inflammatory cytokine production. This increases autoantibody production and predisposes global and macrophage-specific Ppard(-/-) mice to autoimmune kidney disease, a phenotype resembling the human disease systemic lupus erythematosus. Thus, PPAR-delta has a pivotal role in orchestrating the timely disposal of apoptotic cells by macrophages, ensuring that tolerance to self is maintained.
View details for DOI 10.1038/nm.2048
View details for PubMedID 19838202
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Expression of endothelia and lymphocyte adhesion molecules in bronchus-associated lymphoid tissue (BALT) in adult human lung
RESPIRATORY RESEARCH
2009; 10
Abstract
Bronchus-associated lymphoid tissue (BALT) is the secondary lymphoid tissue in bronchial mucosa and is involved in the development of bronchopulmonary immune responses. Although migration of lymphocytes from blood vessels into secondary lymphoid tissues is critical for the development of appropriate adaptive immunity, the endothelia and lymphocyte adhesion molecules that recruit specific subsets of lymphocytes into human BALT are not known. The aim of this study was to determine which adhesion molecules are expressed on lymphocytes and high endothelial venules (HEVs) in human BALT.We immunostained frozen sections of BALT from lobectomy specimens from 17 patients with lung carcinoma with a panel of monoclonal antibodies to endothelia and lymphocyte adhesion molecules.Sections of BALT showed B cell follicles surrounded by T cells. Most BALT CD4+ T cells had a CD45RO+ memory phenotype. Almost all BALT B cells expressed alpha4 integrin and L-selectin. In contrast, 43% of BALT T cells expressed alpha4 integrin and 20% of BALT T cells expressed L-selectin. Almost all BALT lymphocytes expressed LFA-1. HEVs, which support the migration of lymphocytes from the bloodstream into secondary lymphoid tissues, were prominent in BALT. All HEVs expressed peripheral node addressin, most HEVs expressed vascular cell adhesion molecule-1, and no HEVs expressed mucosal addressin cell adhesion molecule-1.Human BALT expresses endothelia and lymphocyte adhesion molecules that may be important in recruiting naive and memory/effector lymphocytes to BALT during protective and pathologic bronchopulmonary immune responses.
View details for DOI 10.1186/1465-9921-10-97
View details for Web of Science ID 000271637400001
View details for PubMedID 19845971
View details for PubMedCentralID PMC2772857
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Targeting tumor-associated macrophages in an experimental glioma model with a recombinant immunotoxin to folate receptor beta
CANCER IMMUNOLOGY IMMUNOTHERAPY
2009; 58 (10): 1577-1586
Abstract
Tumor-associated macrophages (TAMs) are frequently found in glioblastomas and a high degree of macrophage infiltration is associated with a poor prognosis for glioblastoma patients. However, it is unclear whether TAMs in glioblastomas promote tumor growth. In this study, we found that folate receptor beta (FR beta) was expressed on macrophages in human glioblastomas and a rat C6 glioma implanted subcutaneously in nude mice. To target FR beta-expressing TAMs, we produced a recombinant immunotoxin consisting of immunoglobulin heavy and light chain Fv portions of an anti-mouse FR beta monoclonal antibody and Pseudomonas exotoxin A. Injection of the immunotoxin into C6 glioma xenografts in nude mice significantly depleted TAMs and reduced tumor growth. The immunotoxin targeting FR beta-expressing macrophages will provide a therapeutic tool for human glioblastomas.
View details for DOI 10.1007/s00262-009-0667-x
View details for Web of Science ID 000268294400005
View details for PubMedID 19238383
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Systems Biology Analysis of Sjogren's Syndrome and Mucosa-Associated Lymphoid Tissue Lymphoma in Parotid Glands
ARTHRITIS AND RHEUMATISM
2009; 60 (1): 81-92
Abstract
To identify key target genes and activated signaling pathways associated with the pathogenesis of Sjögren's syndrome (SS) by conducting a systems analysis of parotid glands manifesting primary SS or primary SS/mucosa-associated lymphoid tissue (MALT) lymphoma phenotypes.A systems biology approach was used to analyze parotid gland tissue samples obtained from patients with primary SS, patients with primary SS/MALT lymphoma, and subjects without primary SS (non-primary SS controls). The tissue samples were assessed concurrently by gene-expression microarray profiling and proteomics analysis, followed by weighted gene-coexpression network analysis.Gene-coexpression modules related to primary SS and primary SS/MALT lymphoma were significantly enriched with genes known to be involved in the immune/defense response, apoptosis, cell signaling, gene regulation, and oxidative stress. Detailed functional pathway analyses indicated that primary SS-associated modules were enriched with genes involved in proteasome degradation, apoptosis, signal peptides of the class I major histocompatibility complex (MHC), complement activation, cell growth and death, and integrin-mediated cell adhesion, while primary SS/MALT lymphoma-associated modules were enriched with genes involved in translation, ribosome biogenesis and assembly, proteasome degradation, class I MHC signal peptides, the G13 signaling pathway, complement activation, and integrin-mediated cell adhesion. Combined analyses of gene expression and proteomics data implicated 6 highly connected "hub" genes for distinguishing primary SS from non-primary SS, and 8 hub genes for distinguishing primary SS/MALT lymphoma from primary SS.Systems biology analyses of the parotid glands from patients with primary SS and those with primary SS/MALT lymphoma revealed pathways and molecular targets associated with disease pathogenesis. The identified gene modules/pathways provide further insights into the molecular mechanisms of primary SS and primary SS/MALT lymphoma. The identified disease-hub genes represent promising targets for therapeutic intervention, diagnosis, and prognosis.
View details for DOI 10.1002/art.24150
View details for Web of Science ID 000262416600012
View details for PubMedID 19116902
View details for PubMedCentralID PMC2718690
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TSG-6 protein expression in the pancreatic islets of NOD mice
JOURNAL OF MOLECULAR HISTOLOGY
2008; 39 (6): 585-593
Abstract
The histologic hallmark of the development of type 1 diabetes (T1D) is insulitis, characterized by leukocytic infiltration of the pancreatic islets. The molecules controlling the early influx of leukocytes into the islets are poorly understood. Tumor necrosis factor alpha (TNFalpha)-stimulated gene 6 (TSG-6) is involved in inflammation, extracellular matrix formation, cell migration, and development. In the present study, we examined the expression and cellular localization of TSG-6 protein in islets of female non-obese diabetic (NOD) mice using frozen section immunofluorescence staining. Pancreata from nondiabetic (8 and 25 weeks old), prediabetic (230-280 mg/dl blood glucose) and diabetic (>300 mg/dl blood glucose) NOD mice were stained for TSG-6, insulin, CD3, CD11c, Mac3 and CD31. TSG-6 protein was detected in 67% of islets of prediabetic mice, 27% of islets of 25-week old nondiabetic mice, and less than 7% of islets of diabetic mice and 8-week old nondiabetic mice. Lastly, islet-derived TSG-6 protein was localized to the infiltrating CD3 and CD11c positive leukocytes.
View details for DOI 10.1007/s10735-008-9199-5
View details for Web of Science ID 000260958000004
View details for PubMedID 18979174
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Interferon-alpha initiates type 1 diabetes in nonobese diabetic mice
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2008; 105 (34): 12439-12444
Abstract
With the goal of identifying changes in gene expression in CD4(+) T cells during the development of diabetes in the nonobese diabetic (NOD) mouse, we used DNA microarrays to analyze gene expression in CD4(+) T cells from the pancreatic draining lymph nodes of NOD/BDC 2.5 T cell receptor transgenic and WT NOD mice at different ages. At 4 and 6 weeks of age, we found up-regulation of a number of genes that are known to be induced by IFN-alpha. IFN-alpha levels and IFN-alpha-producing plasmacytoid dendritic cells were increased in the PLNs of 3- to 4-week-old NOD mice. Moreover, blockade of IFN-alpha receptor 1 in NOD mice by a neutralizing antibody at 2-3 weeks of age significantly delayed the onset and decreased the incidence of type 1 diabetes, increased the relative number of immature dendritic cells in the PLNs, and enhanced the ability of spleen CD4(+) T cells to produce IL-4 and IL-10. These findings demonstrate that IFN-alpha in the PLNs is an essential initiator in the pathogenesis of type 1 diabetes in NOD mice.
View details for DOI 10.1073/pnas.0806439105
View details for Web of Science ID 000258905700062
View details for PubMedID 18716002
View details for PubMedCentralID PMC2527930
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The LFA-1 and ICAM-1 adhesion pathway mediates the homeostatic migration of lymphocytes from peripheral tissues through lymphatic vessels into lymph nodes
FEDERATION AMER SOC EXP BIOL. 2008
View details for Web of Science ID 000208467700060
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Keratin overexpression levels correlate with the extent of spontaneous pancreatic injury
AMERICAN JOURNAL OF PATHOLOGY
2008; 172 (4): 882-892
Abstract
Mutation of the adult hepatocyte keratins K8 and K18 predisposes to liver disease. In contrast, exocrine pancreas K8 and K18 are dispensable and are co-expressed with limited levels of membrane-proximal K19 and K20. Overexpression of mutant K18 or genetic ablation of K8 in mouse pancreas is well tolerated whereas overexpression of K8 causes spontaneous chronic pancreatitis. To better understand the effect of exocrine pancreatic keratin overexpression, we compared transgenic mice that overexpress K18, K8, or K8/K18, associated with minimal, modest, or large increases in keratin expression, respectively, with nontransgenic wild-type (WT) mice. Overexpression of the type-II keratin K8 up-regulated type-I keratins K18, K19, and K20 and generated K19/K20-containing neocytoplasmic typical or short filaments; however, overexpression of K18 had no effect on K8 levels. K8- and K18-overexpressing pancreata were histologically similar to WT, whereas K8/K18 pancreata displayed age-enhanced vacuolization and atrophy of the exocrine pancreas and exhibited keratin hyperphosphorylation. Zymogen granules in K8/K18 pancreata were 50% smaller and more dispersed than their normal apical concentration but were twice as numerous as in WT controls. Therefore, modest keratin overexpression has minor effects on the exocrine pancreas whereas significant keratin overexpression alters zymogen granule organization and causes aging-associated exocrine atrophy. Keratin absence or mutation is well tolerated after pancreatic but not liver injury, whereas excessive overexpression is toxic to the pancreas but not the liver when induced under basal conditions.
View details for DOI 10.2353/ajpath.2008.070830
View details for Web of Science ID 000254672600005
View details for PubMedID 18349119
View details for PubMedCentralID PMC2276414
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Lack of lymphoid chemokines CCL19 and CCL21 enhances allergic airway inflammation in mice
INTERNATIONAL IMMUNOLOGY
2007; 19 (6): 775-784
Abstract
Lymphoid chemokines CCL19 and CCL21 are crucial for the recruitment of circulating naive T cells into lymph nodes. However, it is not completely known how they contribute to the development of allergic diseases. To determine whether the lack of CCL19 and CCL21 affects allergic airway inflammation, CCL19- and CCL21-deficient [paucity of lymph node T cells (plt/plt)] and wild-type (WT) mice were immunized intra-peritoneally and then challenged intra-nasally with chicken ovalbumin (OVA). Plt/plt mice developed more severe allergic airway inflammation characterized by increased eosinophils and lymphocytes in bronchoalveolar lavage (BAL) and profound inflammation in peribronchiolar and perivascular regions than did WT mice. CD4+ alpha4 integrin+ and CD4+ beta7 integrin+ T cells were significantly increased in the BAL of OVA-immunized and OVA-challenged (OVA/OVA) plt/plt mice compared with OVA/OVA WT mice. Moreover, there were higher levels of IL-4 and IL-13 mRNAs and lower levels of IL-2 and IFN-gamma mRNAs in inflamed lungs of OVA/OVA plt/plt mice compared with OVA/OVA WT mice. Plt/plt mice produced higher levels of total and OVA-specific IgE antibody. Thus, our results suggest that lack of lymphoid chemokines CCL19 and CCL21 enhances allergic airway inflammation by modulating the recruitment of CD4+ T cells into the lung, the balance between Th1 and Th2 cytokines and the IgE production.
View details for DOI 10.1093/intimm/dxm046
View details for Web of Science ID 000248177800010
View details for PubMedID 17513879
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Importance of IFN-gamma-mediated expression of endothelial VCAM-1 on recruitment of CD8(+) T cells into the brain during chronic infection with Toxoplasma gondii
JOURNAL OF INTERFERON AND CYTOKINE RESEARCH
2007; 27 (4): 329-338
Abstract
Interferon-gamma (IFNgamma) is essential for preventing reactivation of chronic infection with Toxoplasma gondii in the brain. We examined the role of IFNgamma on lymphocyte and endothelial adhesion molecule expression and T cell recruitment into the brain during chronic infection with T. gondii in IFNgamma knockout (IFNgamma(-/-)) and wild-type (WT) mice. Although the number of cerebral vessels expressing intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) increased in both WT and IFNgamma(-/-) mice following infection, there were more VCAM-1(+) vessels in brains of infected WT than of infected IFNgamma(-/-) mice; in contrast, numbers of ICAM-1(+) vessels did not differ between strains. We did not detect endothelial E-selectin, P-selectin, MAdCAM-1, or PNAd in any of the brains. Significantly fewer CD8(+) T cells were recruited into brains of infected IFNgamma(-/-) than WT mice. Treatment of infected IFNgamma(-/-) mice with recombinant IFN-gamma restored the expression of VCAM-1 on their cerebral vessels and recruitment of CD8(+) T cells into their brains, confirming an importance of this cytokine for upregulation of VCAM-1 expression and CD8(+) T cell trafficking. In infected WT and IFNgamma(-/-) animals, almost all cerebral CD8(+) T cells were lymphocyte function-associated antigen-1 (LFA-1)(high), CD44(high), and CD62L(neg), and approximately 38% were alpha4beta1 integrin(+). In adoptive transfer of immune spleen cells, pretreatment of the cells with a monoclonal antibody (mAb) against alpha4 integrin markedly inhibited recruitment of CD8(+) T cells into the brain of chronically infected WT mice. These results indicate that IFN-gamma-induced expression of endothelial VCAM-1 and its binding to alpha4beta1 integrin on CD8(+) T cells is important for recruitment of the T cells into the brain during the chronic stage of T. gondii infection, although LFA-1/ICAM-1 interaction may also be involved in this process.
View details for DOI 10.1089/jir.2006.0154
View details for Web of Science ID 000246210500008
View details for PubMedID 17477820
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Regulation of hormone-sensitive lipase in islets
DIABETES RESEARCH AND CLINICAL PRACTICE
2007; 75 (1): 14-26
Abstract
An unique isoform of hormone-sensitive lipase (HSL) is expressed in beta-cells. Recent findings suggest that HSL could be involved in the regulation of glucose stimulated insulin secretion (GSIS), however, these findings are controversial. To test the hypothesis that HSL is involved in control of normal GSIS via changes in its expression and/or activity in response to stimuli, we examined the effects of free fatty acid (FFA) loading and glucagon like peptide-1 (GLP-1) stimulation on the regulation of HSL expression and activity. With prolonged FFA loading, there was increased expression of beta-cell HSL and increased HSL hydrolytic activity in clonal beta-cells. Short-term treatment with GLP-1 increased HSL activity without changing the expression of the beta-cell isoform of HSL. Basal insulin secretion was increased, whereas GLP-1 potentiation of GSIS was decreased in islets isolated from HSL-/- mice, as compared to islets from wild type mice. Furthermore, using PancChip 2.2 cDNA microarrays (NIDDK consortium), the gene expression profile in the islets of HSL-/- mice was compared with wild type mice. Results showed changes in several metabolic pathways due to changes in lipid homeostasis caused by inactivation of HSL. Quantitative PCR for selected genes also revealed changes in genes that are related to insulin secretion, such as UCP-2. Therefore, these results suggest that the beta-cell isoform of HSL is involved in maintaining lipid homeostasis in islets and contributes to the proper control of GSIS.
View details for DOI 10.1016/j.diabres.2006.05.001
View details for Web of Science ID 000243470700003
View details for PubMedID 16765472
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Contact sensitizer potassium dichromate alters lymphocyte populations in draining lymph nodes and blood in mice
TOXICOLOGY MECHANISMS AND METHODS
2007; 17 (8): 475-481
Abstract
ABSTRACT Chromium is a common human contact allergen, but it is not known whether chromates cause contact hypersensitivity by immunological mechanisms similar to those induced by strong haptens. To understand the immunological events of contact hypersensitivity to chromates, we investigated whether and how chromate sensitization alters lymphocyte subsets in draining lymph nodes (DLNs), blood, and spleens in mice. BALB/c mice were sensitized by painting their ears with 0.5% potassium dichromate or vehicle alone on 3 consecutive days. Flow cytometric analysis of lymphocyte surface antigens showed that the chromate exposure significantly increased the percentage of B cells and decreased the percentages of T cells in the DLNs. This was accompanied by a relative increase in T cells and a relative decrease in B cells in peripheral blood. In contrast to the chromate, sodium dodecyl sulfate (a skin irritant) did not affect B cells or T cells in the three compartments. Moreover, sensitization to the chromate led to dose-dependent decreases in the percentages of CD4(+) T cells and CD8(+) T cells in the DLNs. However, CD4(+) and CD8(+) memory T cells were significantly increased in the blood and DLNs of the chromate-sensitized mice. Additionally, the percentage of B cells in the DLNs but not blood was dose-dependently increased in the chromate-sensitized mice. Histologically, B-cell areas were dramatically enlarged in the DLNs of the chromate-sensitized mice. Thus, this report provides basic information to further elucidate the role of individual lymphocyte subsets in contact hypersensitivity to chromates.
View details for DOI 10.1080/15376510701190839
View details for Web of Science ID 000250445100005
View details for PubMedID 20020874
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Protein phosphatase-2A associates with and dephosphorylates keratin 8 after hyposmotic stress in a site- and cell-specific manner
JOURNAL OF CELL SCIENCE
2006; 119 (7): 1425-1432
Abstract
Keratins 8 and 18 (K8 and K18) are regulated by site-specific phosphorylation in response to multiple stresses. We examined the effect and regulation of hyposmotic stress on keratin phosphorylation. K8 phospho-Ser431 (Ser431-P) becomes dephosphorylated in HT29 cells, but hyperphosphorylated on other K8 but not K18 sites in HRT18 and Caco2 cells and in normal human colonic ex vivo cultures. Hyposmosis-induced dephosphorylation involves K8 but not K18, K19 or K20, occurs preferentially in mitotically active cells, and peaks by 6-8 hours then returns to baseline by 12-16 hours. By contrast, hyperosmosis causes K8 Ser431 hyperphosphorylation in all tested cell lines. Hyposmosis-induced dephosphorylation of K8 Ser431-P is inhibited by okadaic acid but not by tautomycin or cyclosporine. The PP2A catalytic subunit co-immunoprecipitated with K8 and K18 after hyposmotic stress in HT29 cells, but not in HRT18 or Caco2 cells where K8 Ser431 becomes hyperphosphorylated. K8 Ser431-P dephosphorylation after hyposmosis was independent of PP2A levels but correlated with increased PP2A activity towards K8 Ser431-P. Therefore, hyposmotic stress alters K8 phosphorylation in a cell-dependent manner, and renders K8 Ser431-P a physiologic substrate for PP2A in HT29 cells as a result of PP2A activation and the physical association with K8 and K18. The divergent hyposmosis versus hyperosmosis K8 Ser431 phosphorylation changes in HT29 cells suggest that there are unique signaling responses to osmotic stress.
View details for DOI 10.1242/jcs.02861
View details for Web of Science ID 000236763900022
View details for PubMedID 16554440
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Keratin 8 overexpression promotes mouse Mallory body formation
JOURNAL OF CELL BIOLOGY
2005; 171 (6): 931-937
Abstract
Keratins 8 and 18 (K8/18) are major constituents of Mallory bodies (MBs), which are hepatocyte cytoplasmic inclusions seen in several liver diseases. K18-null but not K8-null or heterozygous mice form MBs, which indicates that K8 is important for MB formation. Early stages in MB genesis include K8/18 hyperphosphorylation and overexpression. We used transgenic mice that overexpress K8, K18, or K8/18 to test the importance of K8 and/or K18 in MB formation. MBs were induced by feeding 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). Livers of young K8 or K8/K18 overexpressors had no histological abnormalities despite increased keratin protein and phosphorylation. In aging mice, only K8-overexpressing livers spontaneously developed small "pre-MB" aggregates. Only K8-overexpressing young mice are highly susceptible to MB formation after short-term DDC feeding. Thus, the K8 to K18 ratio, rather than K8/18 overexpression by itself, plays an essential role in MB formation. K8 overexpression is sufficient to form pre-MB and primes animals to accumulate MBs upon DDC challenge, which may help explain MB formation in human liver diseases.
View details for DOI 10.1083/jcb.200507093
View details for Web of Science ID 000234053700005
View details for PubMedID 16365160
View details for PubMedCentralID PMC2171301
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The role of TNF-alpha in the pathogenesis of type 1 diabetes in the nonobese diabetic mouse: Analysis of dendritic cell maturation
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2005; 102 (44): 15995-16000
Abstract
TNF-alpha has been linked to the development of type 1 diabetes (T1D). We previously reported that neonatal treatment of nonobese diabetic (NOD) mice with TNF-alpha accelerated the onset of T1D, whereas TNF-alpha blockade in the same time period resulted in a complete absence of diabetes. The mechanisms by which TNF-alpha modulates development of T1D in NOD mice remain unclear. Here we tested the effects of TNF-alpha on the maturation of dendritic cells (DCs) in the NOD mouse. We found that neonatal treatment with TNF-alpha caused an increase in expression of maturation markers on CD11c(+)CD11b(+) DC subpopulations, whereas treatment with anti-TNF-alpha resulted in a decrease in expression of maturation markers in the CD11c(+)CD11b(+) subset. Moreover, neonatal treatment with TNF-alpha resulted in skewed development of a CD8alpha(+)CD11b(-)CD11c(+) DC subset such that TNF-alpha decreases the CD8alpha(+)CD11c(+) DC subset, increases the CD11c(+)CD11b(+) subset, and causes an increase in the expression of CD40 and CD54 on mature DCs capable of inducing immunity. Anti-TNF-alpha-treated mice had an increase in the CD8alpha(+)CD11c(+) DCs. Notably, adoptively transferred naïve CD4(+) T cells from BDC2.5 T cell receptor transgenic mice proliferated in the pancreatic lymph nodes in TNF-alpha-treated NOD mice but not in anti-TNF-alpha-treated mice. Finally, we show that anti-TNF-alpha-treated mice showed immunological tolerance to islet cell proteins. We conclude that TNF-alpha plays an important role in the initiation of T1D in the NOD mouse by regulating the maturation of DCs and, thus, the activation of islet-specific pancreatic lymph node T cells.
View details for Web of Science ID 000233090900051
View details for PubMedID 16247001
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Absence of the major zymogen granule membrane protein, GP2, does not affect pancreatic morphology or secretion
JOURNAL OF BIOLOGICAL CHEMISTRY
2004; 279 (48): 50274-50279
Abstract
The majority of digestive enzymes in humans are produced in the pancreas where they are stored in zymogen granules before secretion into the intestine. GP2 is the major membrane protein present in zymogen granules of the exocrine pancreas. Numerous studies have shown that GP2 binds digestive enzymes such as amylase, thereby supporting a role in protein sorting to the zymogen granule. Other studies have suggested that GP2 is important in the formation of zymogen granules. A knock-out mouse was generated for GP2 to study the impact of the protein on pancreatic function. GP2-deficient mice displayed no gross signs of nutrient malab-sorption such as weight loss, growth retardation, or diarrhea. Zymogen granules in the GP2 knock-out mice appeared normal on electron microscopy and contained the normal complement of proteins excluding GP2. Primary cultures of pancreatic acini appropriately responded to secretagogue stimulation with the secretion of digestive enzymes. The course of experimentally induced pancreatitis was also examined in the knock-out mice because proteins known to associate with GP2 have been found to possess a protective role. When GP2 knock-out mice were subjected to two different models of pancreatitis, no major differences were detected. In conclusion, GP2 is not essential for pancreatic exocrine secretion or zymogen granule formation. It is unlikely that GP2 serves a major intracellular role within the pancreatic acinar cell and may be functionally active after it is secreted from the pancreas.
View details for DOI 10.1074/jbc.M410599200
View details for Web of Science ID 000225229500089
View details for PubMedID 15385539
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Keratin 8 and 18 overexpression is not a prerequisite for Mallory body formation and pancreatic injury
AMER SOC CELL BIOLOGY. 2004: 172A
View details for Web of Science ID 000224648801300
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Oxidative damages in chronic inflammation of a mouse autoimmune disease model
IMMUNOLOGY LETTERS
2004; 95 (2): 233-236
Abstract
Reactive oxygen species are generated in many types of inflammation; it is unclear, however, if inflammation leads to oxidative damage of DNA, proteins and lipids within the inflamed tissues. In this study, we used mice that are homozygous for the alymphoplasia (aly) mutation as a model to determine if inflammation induces oxidative damage in liver and pancreas. We found that 8-hydroxy-2'-deoxyguanosine (8OHdG), which is a product of oxidative DNA damage, increases with age in livers and pancreata of C57BL/6aly/aly (aly/aly) and C57BL/6 wild type (WT) mice. The 8OHdG levels in liver, but not in pancreas, of aged aly/aly mice were significantly higher than those in age-matched WT mice. We showed that aging enhances oxidative protein damage, as measured by carbonylated protein contents, in the pancreata of WT but not aly/aly mice. In contrast, neither aging nor inflammation was associated with lipid damage, as measured by thiobarbituric acid-reactive substances (TBARS), in aly/aly or WT mice. Our results indicate that chronic inflammation in liver but not pancreas leads to increased oxidative damage to DNA, but not to lipids and proteins in aly/aly mouse model.
View details for DOI 10.1016/j.imlet.2004.07.003
View details for Web of Science ID 000225902500016
View details for PubMedID 15388266
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Keratin-8 null mice have different gallbladder and liver susceptibility to lithogenic diet-induced injury
JOURNAL OF CELL SCIENCE
2003; 116 (22): 4629-4638
Abstract
Keratin transgenic mouse models and the association of human keratin mutations with liver disease highlight the importance of keratins in protecting the liver from environmental insults, but little is known regarding keratins and their function in the gallbladder. We characterized keratin expression pattern and filament organization in normal and keratin polypeptide-8 (K8)-null, K18-null and K19-null gallbladders, and examined susceptibility to liver and gallbladder injury induced by a high-fat lithogenic diet (LD) in K8-null mice. The major keratins of normal mouse gallbladder are K8>K19>K18 which become markedly depleted in K8-null mice with minor K18/K19 remnants and limited K7 over-expression. Compensatory K18/K20 protein and RNA overexpression occur in K19-null but not in K18-null gallbladders, probably because of the higher levels of K19 than K18 in normal gallbladder. LD challenge causes more severe liver injury in K8-null than wild-type mice without altering keratin protein levels. In contrast, wild-type and K8-null gallbladders are equally susceptible to LD-induced injury and stone formation, but wild-type gallbladders do overexpress keratins upon LD challenge. LD-induced injury triggers keratin hyperphosphorylation in wild-type livers and gallbladders. Hence, mouse gallbladder K8/K18/K19 expression is induced in response to cholelithiasis injury. A high-fat LD increases the susceptibility of K8-null mice to liver but not gallbladder injury, which suggests that keratin mutations may increase the risk of liver damage in patients with steatohepatitis. Differences between K8-null mouse gallbladder and hepatocyte susceptibility to injury may be related to their minimal versus absent keratin expression, respectively.
View details for DOI 10.1242/jcs.00782
View details for Web of Science ID 000187395500016
View details for PubMedID 14576356
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Lymphocyte homing to bronchus-associated lymphoid tissue (BALT) is mediated by L-selectin/PNAd, alpha(4)beta(1) integrin/VCAM-1, and LFA-1 adhesion pathways
JOURNAL OF EXPERIMENTAL MEDICINE
2003; 197 (10): 1255-1267
Abstract
Bronchus-associated lymphoid tissue (BALT) participates in airway immune responses. However, little is known about the lymphocyte-endothelial adhesion cascades that recruit lymphocytes from blood into BALT. We show that high endothelial venules (HEVs) in BALT express substantial levels of VCAM-1, in marked contrast to HEVs in other secondary lymphoid tissues. BALT HEVs also express the L-selectin ligand PNAd. Anti-L-selectin, anti-PNAd, and anti-LFA-1 mAbs almost completely block the homing of B and T lymphocytes into BALT, whereas anti-alpha4 integrin and anti-VCAM-1 mAbs inhibit homing by nearly 40%. alpha4beta7 integrin and MAdCAM-1 are not involved. Importantly, we found that mAbs against alpha4 integrin and VCAM-1 significantly block the migration of total T cells (80% memory phenotype) but not naive T and B cells to BALT. These results suggest that an adhesion cascade, which includes L-selectin/PNAd, alpha4beta1 integrin/VCAM-1, and LFA-1, targets specific lymphocyte subsets to BALT. This high level of involvement of alpha4beta1 integrin/VCAM-1 is unique among secondary lymphoid tissues, and may help unify lymphocyte migration pathways and immune responses in BALT and other bronchopulmonary tissues.
View details for DOI 10.1084/jem.20010685
View details for Web of Science ID 000183090200004
View details for PubMedID 12756264
View details for PubMedCentralID PMC2193791
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High-quiality RNA from cells isolated by laser capture microdissection
BIOTECHNIQUES
2002; 33 (1): 176-179
Abstract
Laser capture microdissection (LCM) provides a rapid and simple method for procuring homogeneous populations of cells. However, reproducible isolation of intact RNAfrom these cells can be problematic; the sample may deteriorate before or during sectioning, RNA may degrade during slide staining and LCM, and inadequate extraction and isolation methods may lead to poor recovery. Our report describes an optimized protocol for preparation of frozen sections for LCM using the HistoGene Frozen Section Staining Kit. This slide preparation method is combined with the PicoPure RNA Isolation Kitfor extraction and isolation of RNA from low numbers of microdissected cells. The procedure is easy to perform, rapid, and reproducible. Our results show that the RNA isolated from the LCM samples prepared according to our protocol is of high quality. The RNA maintains its integrity as shown by RT-PCR detection of genes of different abundance levels and by electrophoretic analysis of ribosomal RNA. RNA obtained by this method has also been used to synthesize probes for interrogating cDNA microarray analyses to study expression levels of thousands of genes from LCM samples.
View details for Web of Science ID 000176966000022
View details for PubMedID 12139243
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Engagement of the lymphotoxin-beta receptor is required for development of diabetes in non-obese diabetic mice.
ACADEMIC PRESS INC ELSEVIER SCIENCE. 2002: S64
View details for Web of Science ID 000176439600192
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Keratin binding to 14-3-3 proteins modulates keratin filaments and hepatocyte mitotic progression
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2002; 99 (7): 4373-4378
Abstract
Keratin polypeptides 8 and 18 (K8/18) are the major intermediate filament proteins of simple-type epithelia. K18 Ser-33 phosphorylation regulates its binding to 14-3-3 proteins during mitosis. We studied the significance of keratin binding to 14-3-3 in transgenic mice that overexpress wild-type or Ser-33-->Ala (S33A) K18. In S33A but not wild-type K18-overexpressing mice, pancreatic acinar cell keratin filaments retracted from the basal nuclear region and became apically concentrated. In contrast, K18 S33A had a minimal effect on hepatocyte keratin filament organization. Partial hepatectomy of K18-S33A-overexpressing mice did not affect liver regeneration but caused limited mitotic arrest, accumulation of abnormal mitotic figures, dramatic fragmentation of hepatocyte keratin filaments, with retention of a speckled 14-3-3zeta mitotic cell nuclear-staining pattern that usually becomes diffuse during mitosis. Hence, K18 Ser-33 phosphorylation regulates keratin filament organization in simple-type epithelia in vivo. Keratin binding to 14-3-3 may partially modulate hepatocyte mitotic progression, in association with nuclear redistribution of 14-3-3 proteins during mitosis.
View details for Web of Science ID 000174856000045
View details for PubMedID 11917136
View details for PubMedCentralID PMC123655
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Lymphocyte migration to is mediated by vascular inflamed lacrimal glands cell adhesion molecule-1/alpha(4)beta(1) integrin, peripheral node addressin/L-selectin, and lymphocyte function-associated antigen-1 adhesion pathways
AMERICAN JOURNAL OF PATHOLOGY
2001; 159 (2): 671-681
Abstract
Sjogren's syndrome is an autoimmune disease characterized by inflammation and destruction of lacrimal and salivary glands. The development of the inflammation requires the migration of lymphocytes from the blood into these tissues. This migration involves multistep cascades with binding of lacrimal gland endothelial adhesion molecules to their ligands on circulating lymphocytes. We used nonobese diabetic mice, which develop autoimmune-mediated lacrimal gland inflammation, as an experimental model to define the adhesion molecules that control lymphocyte migration into inflamed lacrimal glands. We found that vascular endothelia in inflamed areas of lacrimal gland expressed vascular cell adhesion molecule (VCAM)-1 and the peripheral node addressin (PNAd), but not mucosal addressin cell adhesion molecule-1. Most lymphocytes in the inflamed glands expressed alpha(4) integrin, L-selectin, and lymphocyte function-associated antigen (LFA)-1. In vivo studies revealed that antibodies against VCAM-1, alpha(4) integrin, PNAd, L-selectin, or LFA-1 almost completely blocked lymphocyte migration from blood into inflamed lacrimal glands. There was no inhibition of migration by antibodies against mucosal addressin cell adhesion molecule-1 or alpha(4)beta(7) integrin. These results indicate that endothelial/lymphocyte adhesion cascades involving VCAM-1/alpha(4)beta(1) integrin, PNAd/L-selectin, and LFA-1 control the migration of lymphocytes into inflamed lacrimal gland. These adhesion molecules offer potential therapeutic targets to block the development of lacrimal gland inflammation and destruction.
View details for Web of Science ID 000170356500031
View details for PubMedID 11485925
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Inhibition of 14-3-3 binding to keratins alters mitotic progression and protects from hepatotoxic injury
W B SAUNDERS CO. 2001: A28
View details for Web of Science ID 000168514700137
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Simple epithelial keratins are dispensable for cytoprotection in two pancreatitis models
AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY
2000; 279 (6): G1343-G1354
Abstract
Pancreatic acinar cells express keratins 8 and 18 (K8/18), which form cytoplasmic filament (CF) and apicolateral filament (ALF) pools. Hepatocyte K8/18 CF provide important protection from environmental stresses, but disruption of acinar cell CF has no significant impact. We asked whether acinar cell ALF are important in providing cytoprotective roles by studying keratin filaments in pancreata of K8- and K18-null mice. K8-null pancreas lacks both keratin pools, but K18-null pancreas lacks only CF. Mouse but not human acinar cells also express apicolateral keratin 19 (K19), which explains the presence of apicolateral keratins in K18-null pancreas. K8- and K18-null pancreata are histologically normal, and their acini respond similarly to stimulated secretion, although K8-null acini viability is reduced. Absence of total filaments (K8-null) or CF (K18-null) does not increase susceptibility to pancreatitis induced by caerulein or a choline-deficient diet. In normal and K18-null acini, K19 is upregulated after caerulein injury and, unexpectedly, forms CF. As in hepatocytes, acinar injury is also associated with keratin hyperphosphorylation. Hence, K19 forms ALF in mouse acinar cells and helps define two distinct ALF and CF pools. On injury, K19 forms CF that revert to ALF after healing. Acinar keratins appear to be dispensable for cytoprotection, in contrast to hepatocyte keratins, despite similar hyperphosphorylation patterns after injury.
View details for Web of Science ID 000165507700026
View details for PubMedID 11093958
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Effects of keratin filament disruption on exocrine pancreas-stimulated secretion and susceptibility to injury
EXPERIMENTAL CELL RESEARCH
2000; 255 (2): 156-170
Abstract
Disruption or absence of hepatocyte keratins 8 and 18 is associated with chronic hepatitis, marked hepatocyte fragility, and a significant predisposition to stress-induced liver injury. In contrast, pancreatic keratin disruption in transgenic mice that express keratin 18 Arg89 --> Cys (K18C) is not associated with an obvious pancreatic pathology. We compared the effects of keratin filament disruption on pancreatic acini or acinar cell viability, and on cholecystokinin (CCK)-stimulated secretion, in transgenic mice that overexpress wild-type keratin 18 and harbor normal extended keratin filaments (TG2) and K18C mice. We also compared the response of these mice to pancreatitis induced by a choline-deficient ethionine-supplemented diet or by caerulein. Despite extensive cytoplasmic keratin filament disruption, the apicolateral keratin filament bundles appear intact in the acinar pancreas of K18C mice, as determined ultrastructurally and by light microscopy. No significant pancreatitis-associated histologic, serologic, or F-actin/keratin apicolateral redistribution differences were noted between TG2 and K18C mice. Acinar cell viability and yield after collagenase digestion were lower in K18C than in TG2 mice, but the yields of intact acini and their (125)I-CCK uptake and responses to CCK-stimulated secretion were similar. Our results indicate that keratin filament reorganization is a normal physiologic response to pancreatic cell injury, but an intact keratin cytoplasmic filament network is not as essential in protection from cell injury as in the liver. These findings raise the possibility that the abundant apicolateral acinar keratin filaments, which are not as evident in hepatocytes, may play the cytoprotective role that is seen in liver and other tissues. Alternatively, identical keratins may function differently in different tissues.
View details for Web of Science ID 000085987200003
View details for PubMedID 10694432
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HLA class II transgenic mice: models of the human CD4(+) T-cell immune response
IMMUNOLOGICAL REVIEWS
1999; 172: 335-343
Abstract
This review examines the field of current HLA class II transgenic mouse models and the individual approaches applied in production of these mice. The majority of these mice have been created with the objective of obtaining a disease model with clinical features mimicking human autoimmune disease. The development process of a different type of HLA class II transgenic mice, which are designed to function as a substitute for a normal human immune system in studies of human autoantigens, is described. Several HLA-DR4 transgenic lines with normally expressed HLA-DR4 molecules have been produced. To obtain adequate positive selection of the HLA-DR4-restricted CD4+ T-cell repertoire in these mice it is essential both to introduce a human CD4 transgene, and to delete the murine major histocompatibility complex (MHC) class II molecules. These HLA-DR4 transgenic mice have been used to determine the immunogenic CD4+ T-cell epitopes of several human autoantigenic proteins.
View details for Web of Science ID 000084432700027
View details for PubMedID 10631958
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Anti-CD43 monoclonal antibody L11 flocks migration of T cells to inflamed pancreatic islets and prevents development of diabetes in nonobese diabetic mice
JOURNAL OF IMMUNOLOGY
1999; 163 (10): 5678-5685
Abstract
Nonobese diabetic mice are a well-known model for human insulin-dependent diabetes mellitus. These mice develop autoimmune-mediated inflammation of the pancreatic islets, followed by destruction of the insulin-producing beta cells and development of diabetes. Nonobese diabetic mice also have salivary gland inflammation, and serve as a model for human Sjogren's syndrome. T cells are a prominent component of the inflammatory infiltrate in these sites, and T cell recruitment from the blood is thought to be essential for the initiation and maintenance of pathologic tissue damage. A unique mAb to murine CD43, L11, has recently been shown to block the migration of T cells from blood into organized lymphoid tissues. Here we demonstrate that L11 significantly inhibits T cell migration from blood into inflamed islets and salivary glands. Treatment of nonobese diabetic mice with L11 from 1 to 4 or 8 to 12 wk of age led to significant protection against the development of diabetes. Moreover, protection was long-lived, with decreased incidence of diabetes even months after cessation of Ab administration. When treatment was started at 1 wk of age, L11 inhibited the development of inflammation in pancreatic islets and salivary glands. L11 treatment had no long-term effect on numbers or phenotypes of peripheral lymphocytes. These data indicate that anti-CD43 Abs that block T cell migration may be useful agents for the prevention or treatment of autoimmune diseases including insulin-dependent diabetes mellitus and Sjogren's syndrome.
View details for Web of Science ID 000083638400063
View details for PubMedID 10553098
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L11, a unique anti-CD43 monoclonal antibody, inhibits the adoptive transfer of diabetes and pancreatic islet, salivary gland, and lacrimal gland inflammation in NOD scid mice
CELLULAR IMMUNOLOGY
1999; 194 (1): 112-117
Abstract
L11 is an anti-murine CD43 monoclonal antibody that blocks the migration of T cells from blood into lymphoid tissues. We used a T-cell-mediated adoptive transfer model to evaluate the ability of L11 to inhibit inflammation and destruction in extranodal tissues in the nonobese diabetic (NOD) mouse. Splenocytes from diabetic NOD mice were transferred intravenously into NOD/scid mice. The host mice were treated with L11, negative control antibody, or saline for the first 8 days after transfer. L11 treatment significantly delayed the onset of diabetes and inhibited the development of inflammation in pancreatic islets, salivary gland, and lacrimal gland. These results suggest that L11 may be a useful immunotherapeutic tool for the prevention of T-cell-mediated autoimmune diseases.
View details for Web of Science ID 000081028700014
View details for PubMedID 10357887
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Mutation of a major keratin phosphorylation site predisposes to hepatotoxic injury in transgenic mice
JOURNAL OF CELL BIOLOGY
1998; 143 (7): 2023-2032
Abstract
Simple epithelia express keratins 8 (K8) and 18 (K18) as their major intermediate filament (IF) proteins. One important physiologic function of K8/18 is to protect hepatocytes from drug-induced liver injury. Although the mechanism of this protection is unknown, marked K8/18 hyperphosphorylation occurs in association with a variety of cell stresses and during mitosis. This increase in keratin phosphorylation involves multiple sites including human K18 serine-(ser)52, which is a major K18 phosphorylation site. We studied the significance of keratin hyperphosphorylation and focused on K18 ser52 by generating transgenic mice that overexpress a human genomic K18 ser52--> ala mutant (S52A) and compared them with mice that overexpress, at similar levels, wild-type (WT) human K18. Abrogation of K18 ser52 phosphorylation did not affect filament organization after partial hepatectomy nor the ability of mouse livers to regenerate. However, exposure of S52A-expressing mice to the hepatotoxins, griseofulvin or microcystin, which are associated with K18 ser52 and other keratin phosphorylation changes, resulted in more dramatic hepatotoxicity as compared with WT K18-expressing mice. Our results demonstrate that K18 ser52 phosphorylation plays a physiologic role in protecting hepatocytes from stress-induced liver injury. Since hepatotoxins are associated with increased keratin phosphorylation at multiple sites, it is likely that unique sites aside from K18 ser52, and phosphorylation sites on other IF proteins, also participate in protection from cell stress.
View details for Web of Science ID 000077900300020
View details for PubMedID 9864372
View details for PubMedCentralID PMC2175212
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Effect of keratin filament disruption on exocrine pancreas-stimulated secretion and susceptibility to injury.
AMER SOC CELL BIOLOGY. 1998: 164A
View details for Web of Science ID 000076906700948
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Effects of tumor necrosis factor and lymphotoxin on peripheral lymphoid tissue development
INTERNATIONAL IMMUNOLOGY
1998; 10 (6): 727-741
Abstract
Previously, we have reported that neutralization of surface lymphotoxin (LT-alphabeta) in mice which expressed an LT-beta receptor-Fc fusion protein, driven by the cytomegalovirus promoter, resulted in an array of anatomic abnormalities. We now report that mice which express a tumor necrosis factor (TNF) receptor p60-Fc fusion protein (which neutralizes TNF and soluble LT-alpha3 activity) develop unique lymphoid abnormalities. Our data demonstrate that some aspects of peripheral lymphoid organ development require both surface LT-alphabeta and TNF interacting with their specific receptors. However, these related cytokines are also capable of signaling distinct developmental events. Splenic MAdCAM-1 expression, follicular dendritic cell localization and normal Peyer's patch development all require both surface LT-alphabeta and TNF activity. Marginal zone formation and splenic B cell localization primarily require surface LT-alphabeta-LT-beta receptor interactions. Primary follicle formation was dependent upon TNF receptor(s) engagement. Interestingly spleen, lymph nodes and Peyer's patches from TNF receptor p60-Fc-expressing mice all develop different abnormalities, suggesting distinct pathways of development in these lymphoid organs. Thymus development appears to be independent of these signaling pathways. These results demonstrate that TNF and LT are crucial for normal peripheral, but not central lymphoid organ development.
View details for Web of Science ID 000074419500003
View details for PubMedID 9678753
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Cytoskeletal intermediate filament protein phosphorylation provides a protective physiologic role against liver injury
W B SAUNDERS CO. 1998: A1280
View details for Web of Science ID 000073089605197
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Hepatocyte cytoskeletal keratin binding to 14-3-3 proteins and 14-3-3 regulation of phosphokeratin organization during mitosis
W B SAUNDERS CO. 1998: A1280
View details for Web of Science ID 000073089605198
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Adhesion molecule phenotype of T lymphocytes in inflamed CNS
JOURNAL OF NEUROIMMUNOLOGY
1998; 84 (1): 92-104
Abstract
The phenotype of T cells in the central nervous system (CNS) in two models of chronic inflammation (experimental allergic encephalomyelitis and Corynebacterium parvum-induced inflammation) was compared to that of T cells in gut and chronically inflamed subcutaneous tissue and lung. CNS T cells display a similar phenotype in both inflammatory models, and are phenotypically unique compared to T cells from the other inflamed tissues. T cells from inflamed CNS are mainly CD4+ and are the only population examined that express a typical activated/memory phenotype: CD44high/LFA-1high/ICAM-1high/CD45RBlow. The CNS T cells are alpha4beta7-integrin(negative), but express alpha4-integrin and activated beta1 integrin, suggesting expression of the alpha4beta1-heterodimer in an activated state. In contrast, most T cells in gut express low levels of activated beta1 integrin. The CNS T cells lack expression of alpha6 and alphaE integrin chains and L-selectin. In inflamed CNS and inflamed subcutaneous tissue, approximately 50% of T cells express high affinity ligands for P-selectin while fewer than 10% express high affinity ligands for E-selectin. In summary, our data show that, independent of the inflammatory stimulus, T cells recruited into the inflamed CNS are phenotypically distinct from T cells in other inflamed tissues. This finding leads us to hypothesize the existence of a phenotypically distinct 'CNS-seeking' T lymphocyte population.
View details for Web of Science ID 000073390900012
View details for PubMedID 9600713
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The roles of alpha 4-integrins in the development of insulin-dependent diabetes mellitus
LEUKOCYTE INTEGRINS IN THE IMMUNE SYSTEM AND MALIGNANT DISEASE
1998; 231: 65-83
Abstract
Lymphocyte/endothelial adhesion followed by transendothelial migration is a key event in the development of organ-specific autoimmunity. Selective interactions of cell surface AM regulate lymphocyte migration under normal as well as pathologic inflammatory conditions. NOD mice are an ideal model for investigating the roles of AM in regulation of lymphocyte migration to target organs in autoimmune diseases such as IDDM. Both in vitro and in vivo studies in NOD mice strongly suggest that the mucosal (alpha 4 beta 7/MAdCAM-1) adhesion system and alpha 4-integrin/VCAM-1 appear to be prominent pathways for insulitis development. In contrast, alpha 4-mediated interactions in NOD inflamed salivary and lacrimal gland and in the inflamed CNS of rodents with EAE seem to be dominated by alpha 4-integrins and VCAM-1. The fact that blocking alpha 4-integrin pathways in NOD mice leads to successful interruption of the diabetogenic process suggests that AM provide a potential therapeutic target for human IDDM. Further studies on IDDM patients will prove helpful for understanding IDDM pathogenesis and in providing a basis for designing AM-based therapeutic approaches.
View details for Web of Science ID 000071447200005
View details for PubMedID 9479861
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Involvement of beta(7) integrin and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in the development of diabetes in nonobese diabetic mice
DIABETES
1997; 46 (10): 1542-1547
Abstract
Nonobese diabetic (NOD) mice develop autoimmune-mediated lymphocytic inflammation of pancreatic islets (insulitis) that leads to beta-cell destruction and development of diabetes. Inflamed islets show expression of lymphocyte alpha 4 beta 7 integrin and endothelial mucosal addressin cell adhesion molecule-1 (MAdCAM-1), adhesion molecules involved in tissue-selective migration of lymphocytes to mucosal lymphoid tissues. To elucidate the roles of the mucosal lymphocyte/endothelial adhesion system in the development of diabetes, we treated NOD mice with monoclonal antibody against beta 7 integrin or MAdCAM-1. Treatment of mice from age 7 to 28 days or 8 to 12 weeks with either antibody led to significant and long-standing protection against the spontaneous development of diabetes and insulitis. In contrast, neither treatment prevented the development of salivary gland inflammation (sialadenitis), indicating that the effect was tissue-selective. Monoclonal antibody treatment had no demonstrable effect on numbers or phenotypes of peripheral lymphocytes or on the immune response to pancreatic islet or exogenous antigens. These data indicate that lymphocyte and endothelial adhesion molecules involved in the migration of lymphocytes into mucosal lymphoid tissues play a role in the development of diabetes in NOD mice. Moreover, the results suggest that treatment of humans with antibodies against tissue-selective lymphocyte or endothelial adhesion molecules may selectively inhibit the development of autoimmune diseases such as diabetes.
View details for Web of Science ID A1997XX80000002
View details for PubMedID 9313747
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Disrupted splenic architecture, but normal lymph node development in mice expressing a soluble lymphotoxin-beta receptor-IgG1 fusion protein
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
1996; 93 (23): 13102-13107
Abstract
Early in ontogeny, the secondary lymphoid organs become populated with numerous cells of mesodermal origin which forms both the lymphoid and stromal elements. The critical receptor/ligand interactions necessary for lymphoid organogenesis to occur are for the most part unknown. Although lymphotoxin-alpha (LT alpha) has been shown to be required for normal lymph node, Peyer's patch, and splenic development, it is unclear if soluble LT alpha 3, and/or cell-bound lymphotoxin-alpha beta (LT alpha beta) mediate these developmental events. Here we report that blocking LT alpha beta/lymphotoxin-beta receptor (LT beta R) interaction in vivo by generating mice which express a soluble LT beta R-Fc fusion protein driven by the human cytomegalovirus promoter results in an array of anatomic abnormalities affecting both the spleen and Peyer's patches, but not the lymph nodes. These results demonstrate that surface LT alpha beta ligand plays a critical role in normal lymphoid organ development.
View details for Web of Science ID A1996VT05400078
View details for PubMedID 8917551
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A developmental switch in lymphocyte homing receptor and endothelial vascular addressin expression regulates lymphocyte homing and permits CD4+CD3- cells to colonize lymph nodes
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
1996; 93 (20): 11019-11024
Abstract
IN adult mice, the dominant adhesion molecules involved in homing to lymph nodes are L-selectin homing receptors on lymphocytes and the peripheral lymph node addressins on specialized high endothelial venules. Here we show that, from fetal life through the first 24 hr of life, the dominant adhesion molecules are the mucosal addressin MAdCAM-1 on lymph node high endothelial venules and its counterreceptor, the Peyer's patch homing receptor, integrin alpha 4 beta 7 on circulating cells. Before birth, 40-70% of peripheral blood leukocytes are L-selectin-positive, while only 1-2% expresses alpha 4 beta 7. However, the fetal lymph nodes preferentially attract alpha 4 beta 7-expressing cells, and this can be blocked by fetal administration of anti-MAdCAM-1 antibodies. During fetal and early neonatal life, when only MAdCAM-1 is expressed on high endothelial venules, an unusual subset of CD4 + CD3- cells, exclusively expressing alpha 4 beta 7 as homing receptors, enters the lymph nodes. Beginning 24 hr after birth a developmental switch occurs, and the peripheral node addressins are upregulated on high endothelial venules in peripheral and mesenteric lymph nodes. This switch in addressin expression facilitates tissue-selective lymphocyte migration and mediates a sequential entry of different cell populations into the lymph nodes.
View details for Web of Science ID A1996VL33300091
View details for PubMedID 8855301
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Susceptibility to Hepatotoxicity in transgenic mice that express a dominant-negative human keratin 18 mutant
JOURNAL OF CLINICAL INVESTIGATION
1996; 98 (4): 1034-1046
Abstract
Keratins 8 and 18 (K8/18) are intermediate filament phosphoglycoproteins that are expressed preferentially in simple-type epithelia. We recently described transgenic mice that express point-mutant human K18 (Ku, N.-O., S. Michie, R.G. Oshima, and M.B. Omary. 1995. J. Cell Biol. 131:1303-1314) and develop chronic hepatitis and hepatocyte fragility in association with hepatocyte keratin filament disruption. Here we show that mutant K18 expressing transgenic mice are highly susceptible to hepatotoxicity after acute administration of acetaminophen (400 mg/Kg) or chronic ingestion of griseofulvin (1.25% wt/wt of diet). The predisposition to hepatotoxicity results directly from the keratin mutation since nontransgenic or transgenic mice that express normal human K18 are more resistant. Hepatotoxicity was manifested by a significant difference in lethality, liver histopathology, and biochemical serum testing. Keratin glycosylation decreased in all griseofulvin-fed mice, whereas keratin phosphorylation increased dramatically preferentially in mice expressing normal K18. The phosphorylation increase in normal K18 after griseofulvin feeding appears to involve sites that are different to those that increase after partial hepatectomy. Our results indicate that hepatocyte intermediate filament disruption renders mice highly susceptible to hepatotoxicity, and raises the possibility that K18 mutations may predispose to drug hepatotoxicity. The dramatic phosphorylation increase in nonmutant keratins could provide survival advantage to hepatocytes.
View details for Web of Science ID A1996VE49000022
View details for PubMedID 8770877
View details for PubMedCentralID PMC507520
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The role of cell adhesion molecules in the development of IDDM - Implications for pathogenesis and therapy
DIABETES
1996; 45 (6): 705-710
Abstract
IDDM is a chronic inflammatory disease in which there is autoimmune-mediated organ-specific destruction of the insulin-producing beta-cells in the pancreatic islets of Langerhans. The migration of autoreactive lymphocytes and other leukocytes from the bloodstream into the target organ is of clear importance in the etiology of many organ-specific autoimmune/inflammatory disorders, including IDDM. In IDDM, this migration results in lymphocytic invasion of the islets (formation of insulitis) and subsequent destruction of beta-cells. Migration of lymphocytes from the bloodstream into tissues is a complex process involving sequential adhesion and activation events. This migration is controlled in part by selective expression and functional regulation of cell adhesion molecules (CAMs) on the surface of lymphocytes and vascular endothelial cells or in the extracellular matrix. Understanding the mechanisms that regulate lymphocyte migration to the pancreatic islets will lead to further understanding of the pathogenesis of IDDM. In this article, we summarize the recent advances regarding the function of CAMs in the development of IDDM in animal models and in humans and discuss the potential for developing CAM-based therapies for IDDM.
View details for Web of Science ID A1996UN72400001
View details for PubMedID 8635641
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Increased susceptibility to hepatotoxicity in transgenic mice expressing a dominant-negative human keratin 18 mutant.
W B SAUNDERS CO-ELSEVIER INC. 1996: A1241
View details for Web of Science ID A1996UF73704939
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CHRONIC HEPATITIS, HEPATOCYTE FRAGILITY, AND INCREASED SOLUBLE PHOSPHOGLYCOKERATINS IN TRANSGENIC MICE EXPRESSING A KERATIN-18 CONSERVED ARGININE MUTANT
JOURNAL OF CELL BIOLOGY
1995; 131 (5): 1303-1314
Abstract
The two major intermediate filament proteins in glandular epithelia are keratin polypeptides 8 and 18 (K8/18). To evaluate the function and potential disease association of K18, we examined the effects of mutating a highly conserved arginine (arg89) of K18. Expression of K18 arg89-->his/cys and its normal K8 partner in cultured cells resulted in punctate staining as compared with the typical filaments obtained after expression of wild-type K8/18. Generation of transgenic mice expressing human K18 arg89-->cys resulted in marked disruption of liver and pancreas keratin filament networks. The most prominent histologic abnormalities were liver inflammation and necrosis that appeared at a young age in association with hepatocyte fragility and serum transaminase elevation. These effects were caused by the mutation since transgenic mice expressing wild-type human K18 showed a normal phenotype. A relative increase in the phosphorylation and glycosylation of detergent solubilized K8/18 was also noted in vitro and in transgenic animals that express mutant K18. Our results indicate that the highly conserved arg plays an important role in glandular keratin organization and tissue fragility as already described for epidermal keratins. Phosphorylation and glycosylation alterations in the arg mutant keratins may account for some of the potential changes in the cellular function of these proteins. Mice expressing mutant K18 provide a novel animal model for human chronic hepatitis, and for studying the tissue specific function(s) of K8/18.
View details for Web of Science ID A1995TJ29500015
View details for PubMedID 8522591
View details for PubMedCentralID PMC2120631
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L-SELECTIN AND ALPHA(4)BETA(7) INTEGRIN HOMING RECEPTOR PATHWAYS MEDIATE PERIPHERAL LYMPHOCYTE TRAFFIC TO AKR MOUSE HYPERPLASTIC THYMUS
AMERICAN JOURNAL OF PATHOLOGY
1995; 147 (2): 412-421
Abstract
Before the development of thymic lymphoma, AKR mice undergo a striking lymphoid hyperplasia of the thymic medulla. We have previously shown that there is a marked increase in traffic of B and T lymphocytes from the periphery into the preneoplastic, hyperplastic thymuses of these mice, in contrast to the scant traffic of such cells to normal thymuses. The traffic of lymphocytes to lymph nodes and Peyer's patches is controlled in part by the interaction of lymphocyte adhesion molecules called homing receptors with their tissue-selective endothelial ligands known as vascular addressins. We have investigated the roles of homing receptors and vascular addressins in the traffic of lymphocytes to the AKR hyperplastic thymus. We demonstrate that development of hyperplasia is accompanied by an increase in the number of thymic medullary blood vessels with high endothelial venule morphology and expression of the peripheral node addressin (PNAd) and the mucosal addressin (MAdCAM-1). In vitro and in vivo functional assays show that the addressin/homing receptor pairs PNAd/L-selectin and MAdCAM-1/alpha 4 beta 7 are involved in lymphocyte traffic to the hyperplastic thymus. These results indicate that molecular adhesion mechanisms involved in tissue-selective migration of lymphocytes to peripheral lymph node and to mucosal lymphoid tissues play a role in the recruitment of B and T lymphocytes to the AKR thymus and thus in the pathogenesis of thymic hyperplasia.
View details for Web of Science ID A1995RN76400018
View details for PubMedID 7543735
View details for PubMedCentralID PMC1869832
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EXPRESSION OF BCL-2 PROTEIN AND KI-67 NUCLEAR PROLIFERATION ANTIGEN IN BENIGN AND MALIGNANT CUTANEOUS T-CELL INFILTRATES
JOURNAL OF CUTANEOUS PATHOLOGY
1995; 22 (1): 11-17
Abstract
The bcl-2 protein prolongs cell life by inhibiting apoptosis. Its expression has been studied in a variety of normal tissues and lymphomas but there is minimal information available concerning bcl-2 expression by benign and malignant cutaneous T-cells. Therefore, we investigated bcl-2 expression in a wide variety of cutaneous T-cell infiltrates using one- and two-color immunohistologic techniques. bcl-2 was expressed by the majority of lesional CD3+ T-cells in most cases. This included 22/26 cases of mycosis fungoides (MF), 3/3 cases of non-MF cutaneous T-cell lymphoma, 5/5 cases of lymphomatoid papulosis, 4/4 cases of T-cell rich cutaneous lymphoid hyperplasia, 2/3 cases of bullous pemphigoid, 2/2 cases of discoid lupus erythematosus and 1/1 case of lichen planus. Titration experiments and comparative studies of tonsil section positive controls revealed that, relative to mantle zone B-cells, there was over- expression of bcl-2 by a variable subset of T-cells in most cases. Assessment of multiple biopsies in a subset of MF cases showed stable expression of bcl-2 over intervals of up to two years. In contrast to the widespread expression of bcl-2 in both early and advanced MF skin lesions, abundant expression of the nuclear proliferation antigen, Ki-67, was skewed toward advanced MF skin lesions. Ten percent or more Ki-67+ cells were present in 5% of patients with patches/thin plaques, 38% with moderate plaques, 64% with thick plaques and 100% with tumor nodules.(ABSTRACT TRUNCATED AT 250 WORDS)
View details for Web of Science ID A1995QL26000003
View details for PubMedID 7751472
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A PREDOMINANT ROLE OF INTEGRIN ALPHA(4) IN THE SPONTANEOUS DEVELOPMENT OF AUTOIMMUNE DIABETES IN NONOBESE DIABETIC MICE
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
1994; 91 (26): 12604-12608
Abstract
To elucidate the role of cell adhesion molecules in the pathogenesis of insulin-dependent diabetes mellitus and to determine the predominant lymphocytic homing pathway(s) involved in the selective lymphocytic infiltration of pancreatic islets (insulitis), nonobese diabetic mice were treated with monoclonal antibodies specific for the L-selectin and integrin alpha 4 lymphocyte adhesion molecules. Treatment of neonatal mice with either anti-L-selectin or anti-integrin alpha 4 monoclonal antibodies for the first 4 weeks of life led to a significant and long-term protection against spontaneous occurrence of insulitis and diabetes. The same treatment failed to inhibit lymphocytic infiltration of the salivary glands (sialadenitis). This tissue-specific inhibition of inflammation may be attributed to differences between the pancreas and salivary gland in their expression of endothelial ligands for L-selectin (peripheral vascular addressin) and for integrin alpha 4 (mucosal addressin cell adhesion molecule 1 and vascular cell adhesion molecule 1). Mucosal addressin cell adhesion molecule 1 is highly expressed by vessels within the inflamed islets but was not detected in the salivary glands. In contrast, peripheral vascular addressin- and vascular cell adhesion molecule 1-expressing vessels can be found in almost every area of inflammation within the salivary glands but are seen in only 40-50% of inflamed islets. Anti-L-selectin and anti-integrin alpha 4 treatment had no demonstrable effect on anti-beta-cell autoimmunity or on the immune responses to foreign antigens. Therapeutic treatment with anti-L-selectin after the onset of insulitis from 10 to 14 weeks of age delayed the onset but failed to prevent spontaneous insulin-dependent diabetes mellitus, whereas anti-integrin alpha 4 treatment resulted in a significant and long-lasting suppression of the disease. These data strongly suggest that integrin alpha 4 plays a prominent role in the spontaneous development of insulitis and diabetes in nonobese diabetic mice.
View details for Web of Science ID A1994PY29400052
View details for PubMedID 7528925
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CELL-ADHESION MOLECULES - A SELECTIVE THERAPEUTIC TARGET FOR ALLEVIATION OF IDDM
13th Immunology of Diabetes Workshop
ACADEMIC PRESS LTD. 1994: 859–64
Abstract
Selective homing of autoreactive lymphocytes to the pancreatic islets of Langerhans is essential for triggering the cascade of molecular and cellular interactions which culminate in the specific destruction of the insulin-producing beta-cells. Based upon the sequential multistep model of lymphocyte adhesion to the endothelium, we investigated the possibility of preventing the progression of insulin-dependent diabetes mellitus (IDDM) by selectively blocking L-selectin and alpha 4-integrin homing receptors, which function at different stages of the adhesion process. Treatment of NOD mice with mAb specific for L-selectin or alpha 4-integrin resulted in a significant inhibition of lymphocytic infiltration (insulitis). Both spontaneous development and acute transfer of IDDM were completely prevented by administration of anti-alpha 4-integrin antibody and partially inhibited by anti-L-selectin antibody. The protective effect was of long duration. Interestingly, the autoimmune T cell responses to a panel of beta cell autoantigens and the lymphocytic infiltration of salivary glands (sialadenitis) appeared unaffected by anti-L-selectin or anti-alpha 4-integrin treatment. These data suggest that prevention of lymphocyte homing to the pancreatic islets may provide a selective target for prevention/treatment of IDDM in patients.
View details for Web of Science ID A1994PW77300015
View details for PubMedID 7534080
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EXPRESSION OF HLA-DR4 AND HUMAN CD4 TRANSGENES IN MICE DETERMINES THE VARIABLE REGION BETA-CHAIN T-CELL REPERTOIRE AND MEDIATES AN HLA-DR-RESTRICTED IMMUNE-RESPONSE
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
1994; 91 (13): 6151-6155
Abstract
Inherited susceptibility to rheumatoid arthritis is associated with genes encoding the human major histocompatibility complex class II molecule HLA-DR4. To study the immune function of HLA-DR4 and attempt to generate a murine model of rheumatoid arthritis we have produced triple transgenic mice expressing HLA-DRA*0101, -DRB1*0401, and human CD4. The expression of the HLA transgenes is driven by the promoter of the murine major histocompatibility complex class II I-E alpha gene and was found on murine cells that normally display major histocompatibility complex class II molecules. The expression of the human CD4 transgene is driven by the murine CD3 delta-promoter, and therefore its gene product was found on cells that express murine CD3. In contrast to other HLA-DR and HLA-DQ transgenic mouse lines, the transgenes are functional in our mice. In H-2 I-E-negative transgenic mice, T cells expressing variable region beta chain (V beta) 3, 5, 6, 7, 9, 11, 12, or 13 were either absent or significantly reduced, in contrast to H-2 I-E-negative nontransgenic littermates. In addition, the peptide antigen influenza A virus hemagglutinin 307-319, which binds to the HLA-DRA*0101/-DRB1*0401 heterodimer with high affinity and induces an HLA-DR-restricted and CD4+ T-cell response in humans, also induced a T-cell response in the triple transgenic mice but not in nontransgenic littermates. Thus, these transgenic mice should permit extensive testing of the antigen-presentation capabilities of the HLA-DRA*0101/-DRB1*0401 molecule.
View details for Web of Science ID A1994NT46100086
View details for PubMedID 8016129
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EXPRESSION OF CLASS-II MAJOR HISTOCOMPATIBILITY ANTIGENS BY KERATINOCYTES IN CUTANEOUS T-CELL LYMPHOMA
INTERNATIONAL JOURNAL OF DERMATOLOGY
1994; 33 (5): 346-350
Abstract
Expression of various class II MHC antigens by lesional keratinocytes may play an important role in the pathophysiology of a wide variety of human dermatoses including cutaneous T cell lymphoma (CTCL). Nevertheless, there is relatively little information available concerning the concurrent expression of HLA-DR, -DP, and -DQ class II MHC antigens in CTCL. Therefore, our aim in this study was to determine the prevalence, localization, extent, temporal sequence, and consistency of class II MHC antigen expression by lesional keratinocytes in CTCL.We used a semiquantitative immunohistologic analysis to analyze HLA-DR, -DP, and -DQ expression by lesional keratinocytes in 66 skin biopsies obtained from 39 patients with CTCL.Class II MHC antigen expression by keratinocytes was observed in 77% of cases. Expression was detected on the cytoplasmic membrane and within the cytoplasm. It varied among cases from focal to confluent. There was a hierarchy of antigen expression in terms of both extent and time course. HLA-DR was expressed first and most extensively, followed by HLA-DP and then HLA-DQ. Comparative studies of multiple serial or concurrent active lesions from 13 cases indicated that the overall pattern and extent of antigen expression was relatively constant within individual patients.There was no apparent correlation between class II MHC antigen expression and the clinical stage of disease, the type of CTCL skin lesion, or the overall density of the lesional T cell infiltrate. The hierarchy of keratinocyte class II MHC antigen expression observed in this study paralleled that noted in earlier studies of cultured keratinocytes exposed to recombinant interferon-gamma in vitro. This suggests that lesional cytokine levels may be the critical factor governing class II MHC antigen expression by lesional keratinocytes in CTCL.
View details for Web of Science ID A1994NJ59200011
View details for PubMedID 8039974
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THE HUMAN PERIPHERAL LYMPH-NODE VASCULAR ADDRESSIN - AN INDUCIBLE ENDOTHELIAL ANTIGEN INVOLVED IN LYMPHOCYTE HOMING
AMERICAN JOURNAL OF PATHOLOGY
1993; 143 (6): 1688-1698
Abstract
The extravasation of blood-borne lymphocytes into organized lymphoid tissues and sites of chronic inflammation is directed in part by interactions of lymphocyte surface adhesion molecules, known as homing receptors, with tissue-selective endothelial ligands called vascular addressins. In mice and humans, lymphocyte L-selectin and the peripheral lymph node addressin (PNAd) form a homing receptor-endothelial ligand pair involved in lymphocyte traffic to peripheral lymph node (PLN). We have examined the tissue distribution and function of human PNAd, using monoclonal antibody MECA-79 and in vitro assays of L-selectin-dependent lymphocyte binding. We demonstrate that PNAd is expressed by human high endothelial venules (HEV) in lymphoid tissues which support lymphocyte adhesion via a PLN-associated recognition system. MECA-79 inhibits adhesion to these HEV of a cell line that binds predominantly via the PLN-homing receptor, L-selectin, but has no effect on adhesion by a mucosal HEV-binding cell line. Furthermore, MECA-79 blocks binding of human peripheral blood mononuclear cells to both PLN and tonsil HEV, but not significantly to HEV in the appendix. In addition, we demonstrate PNAd induction on venules at chronic inflammatory sites in humans, particularly sites with severe or long-standing chronic inflammatory involvement. These results confirm that PNAd functions as a PLN vascular addressin in humans, and that in addition to directing normal lymphocyte recirculation to lymph nodes and tonsils, this addressin likely participates in lymphocyte recruitment to sites of chronic inflammation.
View details for Web of Science ID A1993ML23400020
View details for PubMedID 8256856
View details for PubMedCentralID PMC1887255
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VASCULAR ADDRESSINS ARE INDUCED ON ISLET VESSELS DURING INSULITIS IN NONOBESE DIABETIC MICE AND ARE INVOLVED IN LYMPHOID-CELL BINDING TO ISLET ENDOTHELIUM
JOURNAL OF CLINICAL INVESTIGATION
1993; 92 (5): 2509-2515
Abstract
In the nonobese diabetic (NOD) mouse, lymphocytic and monocytic infiltration of the pancreatic islets leads to beta cell destruction. To investigate the mechanisms by which lymphocytes enter the NOD pancreas, pancreata were immunostained using monoclonal antibodies to a variety of adhesion molecules known to be involved in lymphocyte binding to vascular endothelium, an initial step in the migration of lymphocytes from blood into organized lymphoid and inflamed tissues. These adhesion molecules include: lymphocyte homing receptors involved in tissue-selective binding of lymphocytes to peripheral lymph node (L-selectin) or mucosal lymphoid tissue (LPAM-1, alpha 4 beta 7-integrin) high-endothelial venules (HEV); and HEV ligands peripheral vascular addressin (PNAd) and mucosal vascular addressin (MAdCAM-1). In NOD pancreata, alpha 4 beta 7 is expressed on most infiltrating cells at all stages of insulitis, whereas L-selectin expression is more pronounced on cells in the islets at later stages. During the development of insulitis, MAdCAM-1 and to a lesser extent PNAd became detectable on vascular endothelium adjacent to and within the inflamed islets. The Stamper-Woodruff in vitro assay was used to examine lymphoid cell binding to such vessels. These functional assays show that both the mucosal (MAdCAM-1/alpha 4 beta 7) and the peripheral (PNAd/L-selectin) recognition systems are involved in this binding. Our findings demonstrate that expression of peripheral and mucosal vascular addressins is induced on endothelium in inflamed islets in NOD pancreas, and that these addressins participate in binding lymphoid cells via their homing receptors. This suggests that these adhesion molecules play a role in the pathogenesis of diabetes in these mice by being involved in the migration of lymphocytes from blood into the inflamed pancreas.
View details for Web of Science ID A1993MF29100054
View details for PubMedID 7693764
View details for PubMedCentralID PMC288436
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L-SELECTIN MEDIATES NEUTROPHIL ROLLING IN INFLAMED VENULES THROUGH SIALYL LEWIS(X)-DEPENDENT AND LEWIS(X)-INDEPENDENT RECOGNITION PATHWAYS
BLOOD
1993; 82 (1): 182-191
Abstract
The glycoprotein (GP) L-selectin initiates adhesive interactions between leukocytes and endothelial cells (EC). It functions as a lymphocyte-lectin homing receptor recognizing carbohydrate determinants of the peripheral lymph node addressing on high endothelial venules. It also mediates neutrophil rolling, the earliest interaction of neutrophils with acutely inflamed venules. Neutrophil L-selectin presents sialyl-LewisX (sLe(X)) as a ligand to P- and E-selectin in vitro, and we have proposed that this is a major mechanism of L-selectin-mediated rolling in vivo. In contrast, the contribution of neutrophil L-selectin as a receptor protein recognizing one (or more) ligand(s) on inflamed EC is unclear. To address this question, an sLe(X)-negative murine pre-B cell line, L1-2, that can neither bind vascular selectins nor roll in inflamed rabbit venules, was transfected with human L-selectin cDNA. L-selectin expression in stable transfectants was sufficient to confer significant rolling in vivo. Rolling was unaffected by neuraminidase treatment but completely blocked by anti-L-selectin monoclonal antibody (MoAb) DREG-56. Thus, L-selectin can initiate leukocyte interactions with EC determinants potentially through recognition of endothelial carbohydrates. In contrast, when human neutrophils were tested, rolling was reduced, but not abolished, by MoAb DREG-56. Likewise, treatment with neuraminidase or anti-sLe(X) MoAbs decreased, but did not abrogate, neutrophil rolling, consistent with residual EC recognition via L-selectin. Combination of MoAb DREG-56 and neuraminidase resulted in almost complete loss of rolling, as did removal of glycosylated L-selectin by chymotrypsin. Together with the demonstrable rolling of L-selectin transfectants, our results support the concept of a bidirectional interaction between L-selectin bearing sLe(X) on neutrophils and activated EC in vivo. These findings also suggest that L-selectin may mediate rolling of lymphocytes that lack carbohydrate ligands for E- or P-selectin, although probably less efficiently than through bidirectional recognition.
View details for Web of Science ID A1993LL36600025
View details for PubMedID 7686786
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BIDIRECTIONAL RECEPTOR-LIGAND RECOGNITION PATHWAYS MEDIATE NEUTROPHIL ROLLING INVIVO
FEDERATION AMER SOC EXP BIOL. 1993: A269
View details for Web of Science ID A1993KP97401560
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EFFECTS OF FISH OIL ON GRAFT ARTERIOSCLEROSIS AND MHC CLASS-II ANTIGEN EXPRESSION IN RAT HETEROTOPIC CARDIAC ALLOGRAFTS
JOURNAL OF HEART AND LUNG TRANSPLANTATION
1991; 10 (6): 1004-1111
Abstract
The effect of fish oil on accelerated graft coronary arteriosclerosis was assessed in Lewis to Brown-Norway rat heterotopic cardiac allografts. Twelve Brown-Norway rats were supplemented with 2 ml/kg/day of fish oil (68.3 mg eicosopentaenoic acid and 47.5 mg decosahexaenoic acid per milliliter). Eleven additional animals, receiving an isocaloric amount of safflower oil, served as control. All diets began 1 week before operation. Immunosuppression was obtained with low-dose cyclosporine (2 mg/kg/d). When killed (100 days), there were no significant differences in percentage weight gain, graft function, or histologic rejection score. Although lipid profiles were comparable, total cholesterol:high-density lipoprotein ratio was marginally higher in animals treated with fish oil (p = 0.069). Mean percentage luminal occlusion (before and after correcting for differences in size between coronary vessels analyzed) and average intimal thickness were similar between animals treated with fish oil and safflower oil as assessed by computer-assisted digitized, morphometric planimetry. In all allografts, donor interstitial dendritic cells were repopulated with recipient dendritic cells. The major histocompatibility complex class II cell density in the fish oil group did not differ significantly from rats supplemented with safflower oil (1.48 +/- 0.68 vs 1.48 +/- 0.65 cells per mm2, p = 0.995). In conclusion, fish oil did not exert any beneficial effect over safflower oil in terms of graft coronary arteriosclerosis, histologic rejection, or plasma lipids.(ABSTRACT TRUNCATED AT 250 WORDS)
View details for PubMedID 1756147
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TRAFFIC OF PERIPHERAL LYMPHOCYTE-B AND LYMPHOCYTE-T TO HYPERPLASTIC, PRENEOPLASTIC THYMUSES OF AKR MICE
AMERICAN JOURNAL OF PATHOLOGY
1991; 138 (4): 1015-1025
Abstract
AKR mice develop hyperplasia of the thymus before the development of retrovirus-associated lymphoma at that site. This hyperplasia, first detectable in AKR/J mice by 4 weeks of age and in AKR/C mice by 4 to 5 months of age, is characterized by an enlarged thymic medulla that contains T and B lymphocytes. In contrast to the general population of thymocytes, most of these T and B lymphocytes have a mature immunophenotype that includes expression of high levels of the MEL-14-defined (gp90) 'homing receptor' for peripheral lymph node high endothelial venules. In vivo homing studies reveal a marked increase in traffic of peripheral lymphocytes (T more than B) to the hyperplastic thymuses of old AKR mice as compared to histologically normal thymuses of age-matched BALB/c and C57BL/Ka mice or young AKR mice. These changes correlate chronologically with changes in retrovirus antigen expression in AKR thymuses and suggest a role for the traffic of lymphocytes from the periphery to the thymus in response to local antigenic stimulation in the pathogenesis of thymic hyperplasia in AKR mice.
View details for Web of Science ID A1991FF06700025
View details for PubMedID 2012169
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DISCORDANT EXPRESSION OF ANTIGENS BETWEEN INTRAEPIDERMAL AND INTRADERMAL T-CELLS IN MYCOSIS-FUNGOIDES
AMERICAN JOURNAL OF PATHOLOGY
1990; 137 (6): 1447-1451
Abstract
Using immunohistochemical methods, the authors studied the expression of pan-T- and majority-T-cell antigens (CD5, CD2, CD3, TCR-beta, CD7) and T-cell subset antigens (CD4, CD8) in cutaneous T cells in mycosis fungoides (MF) (177 biopsies from 124 patients) and a variety of inflammatory lesions (45 biopsies from 45 patients). The authors detected the absence of pan-T- or majority-T-cell antigens, or of both T-cell subset antigens, from T cells in the epidermis but not the dermis in 15 MF biopsies (8%) from 11 MF patients (9%), but in none of the inflammatory skin lesions. The opposite picture, characterized by lack of antigen expression by the dermal T cells only, was not seen in any of the MF or inflammatory lesions. The absence of antigen expression by epidermal but not dermal T cells, which the authors have termed antigen discordance, was most prevalent for CD5, CD7, and TCR-beta, each being discordant in 6% to 7% of MF cases or patients tested. Among the MF biopsies showing antigen discordance, 14 of 15 biospies (93%) from 10 of 11 patients (91%) were discordant for two or more antigens. Antigen discordance was not an artifact of treatment, because none of the patients showing discordance was receiving treatment at the time of their initial discordant biopsy. The discordance was the only immunophenotypic abnormality detected in 8 of 15 (53%) of the discordant MF biopsies. Thus, this antigen discordance was an important diagnostic feature that allowed the immunophenotypic distinction of MF from a variety of inflammatory skin lesions.
View details for Web of Science ID A1990EP24300020
View details for PubMedID 2260631
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LYMPHOKINES IN AUTOIMMUNITY - THE NONOBESE DIABETIC (NOD) MODEL SYSTEM
MARY ANN LIEBERT INC PUBL. 1990: 593
View details for Web of Science ID A1990EA86500114
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IMMUNE-DEFICIENCY DUE TO HIGH COPY NUMBERS OF AN A BETA-KAPPA-TRANSGENE
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
1990; 87 (18): 7319-7323
Abstract
Because allelic polymorphism of the major histocompatibility complex class II antigens affects the immune response at several levels, we wished to characterize the contribution of a particular alpha or beta chain in vivo using transgenic mice. We have established and characterized 12 lines of H-2s/s mice carrying from 1 to 65 copies of an Ak beta transgene. The transgene was coexpressed with the endogenous allele in a tissue-specific manner, and Ak beta mRNA expression correlated well with transgene copy number. High copy number (extreme overexpression) of the transgene was associated with a variety of defects, including a significant reduction in Ia cell-surface expression, a severe decrease in B-cell number, abnormal extramedullary granulopoiesis, and an increased susceptibility to infection. In this paper we describe in detail the phenotype associated with high copy numbers of the Ak beta transgene. The defects we have observed may be relevant to similar phenomena seen in other transgenic mice. In addition, these mice have fortuitously provided a system in which to assess the effect of various levels of class II cell-surface expression in the thymus on selection of the T-cell repertoire.
View details for Web of Science ID A1990DZ45300081
View details for PubMedID 2119506
View details for PubMedCentralID PMC54735
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THE EFFECT OF EXCESS BETA-CHAIN SYNTHESIS ON CELL-SURFACE EXPRESSION OF ALLELE-MISMATCHED CLASS-II HETERODIMERS INVIVO
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
1990; 87 (18): 7314-7318
Abstract
We have recently described 12 lines of H-2s/s mice carrying from 1 to 65 copies of an A beta k transgene. The transgene was coexpressed with the endogenous allele, and A beta K mRNA expression correlated well with transgene copy number. Overexpression of the transgene was associated with a variety of defects, including a significant reduction in I-A cell-surface expression. In this paper, we assess the effect of increased levels of A beta k mRNA synthesis on I-A cell-surface expression in these mice. Crossing representatives from several lines of A beta k mice to A alpha k transgenic mice demonstrated that the A beta k mRNA was translated and expressed at high levels on the cell surface in association with A alpha k. In H-2s/s (A alpha s /A beta s) mice carrying greater than 10 copies of the A beta k transgene, excess A beta k mRNA and protein synthesis did drive cell-surface expression of the less favored A alpha s/A beta k heterodimers. However, the highest levels of A beta k detected on the cell surface were only 50-70% of those observed in [B10.A(4R) x nontransgenic]F1 controls. Maximum levels of A alpha s/A beta k cell-surface expression were accompanied by a significant reduction in A alpha s/A beta s expression. Unpaired and improperly paired complexes were not detected intracellularly and appeared to be degraded quite rapidly. Thus, only a fraction of the chains competing for pairing reached the cell surface under conditions of asymmetric chain synthesis in these mice. This markedly reduced total Ia cell-surface levels in mice carrying greater than 10 copies of the A beta k transgene.
View details for Web of Science ID A1990DZ45300080
View details for PubMedID 1698295
View details for PubMedCentralID PMC54734
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A UNIQUE PHENOTYPE OF SKIN-ASSOCIATED LYMPHOCYTES IN HUMANS - PREFERENTIAL EXPRESSION OF THE HECA-452 EPITOPE BY BENIGN AND MALIGNANT T-CELLS AT CUTANEOUS SITES
AMERICAN JOURNAL OF PATHOLOGY
1990; 136 (5): 1053-1068
Abstract
It has been proposed that the skin is a functionally unique compartment of the immune system, although little direct evidence supporting this hypothesis has been presented. Here we show that lymphocyte populations at cutaneous sites can be differentiated from otherwise similar populations at noncutaneous sites by their preferential expression of an epitope defined by the MAb HECA-452. This MAb recognizes a predominantly 200-kd cell-surface glycoprotein present on about 16% of peripheral blood T cells, including both CD4+ and CD8+ T cells (17% and 11% HECA-452+, respectively), as well as TCR-delta-bearing T cells (32%+). Most thymocytes (99%) lacked HECA-452 antigen expression, and essentially all the HECA-452+ peripheral blood T cells were found in the adhesion molecule high, CD45R low putative memory cell subset, findings suggesting that HECA-452 expression develops peripherally as a consequence of antigenic stimulation. However, the HECA-452 antigen is not a conventional activation antigen because it was not upregulated with mitogen stimulation of peripheral blood T cells. Most significantly, among 54 diverse specimens of normal/reactive lymphoid tissues and sites of chronic inflammation, there was a clear association of lymphocyte HECA-452 expression and cutaneous location. In extracutaneous sites (n = 38) only about 5% of lymphocytes within the T-cell areas of these tissues expressed this antigen, whereas in inflammatory skin lesions (n = 16), 85% were HECA-452+. The association of HECA-452 expression and cutaneous location was also seen in a series of T-cell lymphomas. The malignant cells of 16 of 18 cases of epidermotropic (patch/plaque) stage mycosis fungoides were HECA-452+, as well as 2 of 7 nonmycosis fungoides peripheral T-cell lymphomas in skin. In contrast, this antigen was not expressed in thymic (lymphoblastic) lymphomas (n = 14), nonepidermotropic (tumor) stage mycosis fungoides (n = 5), and noncutaneous peripheral T-cell lymphomas (n = 15). Among lymphocytes, the preferential expression of the HECA-452 determinant by cutaneous T cells supports the hypothesis that the skin constitutes a immunologically unique lymphoid tissue and suggests that this molecule may play a role in either lymphocyte homing to skin or in lymphocyte interactions with the epidermis.
View details for Web of Science ID A1990DG37000007
View details for PubMedID 1693467
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PREVENTION OF DIABETES IN NONOBESE DIABETIC MICE BY TUMOR NECROSIS FACTOR (TNF) - SIMILARITIES BETWEEN TNF-ALPHA AND INTERLEUKIN-1
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
1990; 87 (3): 968-972
Abstract
The role of tumor necrosis factor alpha (TNF-alpha) in the pathogenesis of autoimmune diabetes mellitus was tested in the nonobese mouse (NOD) model system. The effects of TNF-alpha were assessed on three levels: (i) insulitis development, (ii) development of overt diabetes, (iii) adoptive transfer of diabetes by splenic lymphocytes. Spontaneous diabetes mellitus was blocked in NOD mice by long-term treatment with recombinant TNF-alpha. Treatment with TNF-alpha caused a significant reduction in the lymphocytic infiltration associated with the destruction of the insulin-producing beta cells. Class II major histocompatibility complex Ia expression by islet cells was not up-regulated by TNF-alpha. Moreover, TNF-alpha was able to suppress the induction of diabetes in adoptive transfer of lymphocytes from diabetic female mice to young nondiabetic male NOD mice. These activities of TNF-alpha were shared by interleukin 1 alpha in this system. These studies have implications for the pathogenesis and therapy of autoimmune diabetes mellitus.
View details for Web of Science ID A1990CM07700025
View details for PubMedID 2405400
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INHIBITION OF ADOPTIVE TRANSFER AND DEVELOPMENT OF SPONTANEOUS DIABETES-MELLITUS IN NONOBESE DIABETIC MICE BY TNF-ALPHA
2ND INTERNATIONAL CONF ON TUMOR NECROSIS FACTOR AND RELATED CYTOKINES
KARGER. 1990: 222–227
View details for Web of Science ID A1990BQ33B00028
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THE EFFECT OF COPY NUMBER ON MESSENGER-RNA AND CELL-SURFACE EXPRESSION OF AN A-BETA-K TRANSGENE
INTERNATIONAL CONF ON TRANSGENIC MICE AND MUTANTS IN MHC RESEARCH
SPRINGER-VERLAG BERLIN. 1990: 143–154
View details for Web of Science ID A1990BR51T00020
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LYMPHOMAS PRESENTING AS HISTOLOGICALLY UNCLASSIFIED NEOPLASMS - CHARACTERISTICS AND RESPONSE TO TREATMENT
JOURNAL OF CLINICAL ONCOLOGY
1989; 7 (9): 1281-1287
Abstract
Malignant lymphoma is frequently diagnosed when immunohistochemical techniques are applied to otherwise unclassified neoplasms. In this analysis of 35 patients with a histologically unclassified neoplasm that expressed leukocyte-common antigen(s) (LCA), actuarial survival was 63%, and 45% of patients were free from disease progression at 30 months following treatment as for lymphoma. The clinical features at diagnosis and the results of combination chemotherapy were found to be similar to a group of patients with a diagnosis of diffuse large-cell lymphoma (DLCL) concurrently treated at this institution. This study further emphasizes the importance of improved diagnostic techniques in the management of histologically unclassified tumors.
View details for Web of Science ID A1989AM61500015
View details for PubMedID 2671285
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EXPRESSION OF T-CELL RECEPTOR ANTIGENS IN MYCOSIS-FUNGOIDES AND INFLAMMATORY SKIN-LESIONS
JOURNAL OF INVESTIGATIVE DERMATOLOGY
1989; 93 (1): 116-120
Abstract
Using immunohistologic methods, we studied the expression of the T-cell receptor (TCR)-associated antigens CD3, TCR-beta, and TCR-delta by cutaneous T cells in mycosis fungoides (MF) (36 patients) and a variety of inflammatory diseases (16 patients). Most T cells in the inflammatory diseases and patch/plaque mycosis fungoides expressed the immunophenotype characteristic of the vast majority of mature peripheral T cells: CD3+ TCR-beta+ TCR-delta-. In contrast, abnormal CD3/TCR-beta antigen expression was seen in 3 of 6 cases (50%) of tumor stage mycosis fungoides. Furthermore, we were able to document its evolution from the normal pattern present in earlier patch/plaque lesions of the two cases in which serial biopsies were available for study. Divergence of epidermal versus dermal CD3/TCR-beta antigen expression was seen in 2 of 34 (6%) of biopsies of patch/plaque mycosis fungoides but not in inflammatory controls. The TCR-delta+ cells were generally rare regardless of diagnosis. We conclude that inflammatory skin diseases and most patch/plaque mycosis fungoides are typically composed of T lymphocytes that resemble mature peripheral T cells in regard to their expression of TCR-associated antigens. In contrast, aberrant patterns of TCR-associated antigen expression can be seen in tumor stage MF, and, more rarely in patch/plaque MF.
View details for Web of Science ID A1989AG41600020
View details for PubMedID 2473133
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TRAFFIC OF MATURE LYMPHOCYTES INTO THE MOUSE THYMUS
WORKSHOP ON THE THYMUS : HISTOPHYSIOLOGY AND DYNAMICS IN THE IMMUNE SYSTEM
KLUWER ACADEMIC PUBL. 1989: 141–48
Abstract
The thymus is not generally considered to participate in bi-directional peripheral lymphocyte recirculation. We have demonstrated the entry of peripheral lymph node T cells using transfers between Thy-1 congenic mice. These peripheral T cells that enter the thymus bear an essentially medullary (or peripheral) phenotype and on section stains are confined to the medulla where they constitute 0.2-0.3% of the cells. These cells are remarkable for their frequent expression of the peripheral node homing receptor MEL-14 and for their persistence. Using transferred fluorescent labeled cells we also identify the entry of peripheral B cells into the thymus. Possible roles for peripheral B and T cells in the thymus include participation in thymocyte maturation or selection, the generation of thymic pathology and reactions to thymic pathologic processes.
View details for Web of Science ID A1989CH41200003
View details for PubMedID 2575807
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RARE PERIPHERAL T-CELLS MIGRATE TO AND PERSIST IN NORMAL MOUSE THYMUS
JOURNAL OF EXPERIMENTAL MEDICINE
1988; 168 (5): 1929-1934
Abstract
The traffic of T cells between the thymus and peripheral lymphoid organs is generally thought to be unidirectional. Using a technique of lymphocyte transfer between Thy-1 congenic mice, we demonstrate here the entry of rare peripheral lymph node T cells into the normal mouse thymus. At time points from 3 h to 24 wk after transfer, donor peripheral T cells were present in the host thymus, mainly as scattered single cells confined to the medulla. At 2 wk after transfer, donor T cells constituted 0.2% of the medullary thymocytes (compared with 11% of the peripheral lymph node T cells). As a population, these cells exhibited a stable mature immunophenotype (Ly-1hi, PNAlo, and mixed L3T4- and Lyt-2+). A minority of the donor T cells expressed high levels of the MEL-14 "homing receptor". The thymic medulla thus exhibits features of a peripheral lymphoid organ but differs in its low rate of turnover of recirculating T cells.
View details for Web of Science ID A1988Q904300031
View details for PubMedID 2903215
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EXPRESSION OF T-CELL RECEPTOR-DELTA CHAINS IN BENIGN AND MALIGNANT T-LINEAGE LYMPHOPROLIFERATIONS
AMERICAN JOURNAL OF PATHOLOGY
1988; 132 (3): 401-405
Abstract
Recent studies in both human and murine systems have demonstrated the existence of a second CD3-associated T cell receptor (the gamma delta-TCR) distinct from the alpha beta heterodimer associated with antigen recognition by classical T cells. Using a monoclonal antibody specific for the delta component of the human gamma delta-TCR, the expression of this antigen in both benign, reactive lymphoid tissues and T lineage lymphomas was studied with immunohistologic techniques. In the normal thymus, TCR-delta+ cells constituted less than 5% of the CD3+ thymocytes and were located primarily in the medulla or juxtamedullary cortex. Within the T zones of 16 histologically varied reactive peripheral lymphoid tissues, including four patients with marked predominantly paracortical hyperplasia, the authors identified from less than 1% to a maximum of 5% TCR-delta+ cells. While these results are consistent with the hypothesis that TCR-gamma delta+ cells comprise a small distinct subpopulation of peripheral T cells in humans, selective localization or recruitment of these cells could not be demonstrated in any of a number of tissues or reactive situations. Among 62 T lineage lymphomas, including 14 CD3+/TCR-beta- cases, only two TCR-delta+ neoplasms were identified, both lymphoblastic lymphomas displaying the CD3+/CD4-/CD8- phenotype known to be associated with normal TCR-gamma delta+ T cells. Because the majority of CD3+/TCR-beta- lymphomas did not display TCR-delta, these results argue against the hypothesis that the high incidence of CD3/TCR-beta discordance noted in T lineage lymphomas represents preferential transformation of the TCR-delta-expressing subset.
View details for Web of Science ID A1988Q131200001
View details for PubMedID 3261945
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AN IMMUNOPEROXIDASE STUDY OF RENAL-CELL CARCINOMAS - CORRELATION WITH NUCLEAR GRADE, CELL TYPE, AND HISTOLOGIC PATTERN
HUMAN PATHOLOGY
1988; 19 (8): 980-987
Abstract
We applied a panel of antibodies to formalin-fixed, paraffin-embedded sections of 55 renal cell carcinomas using a three-stage immunoperoxidase technique. The antibody panel included two anti-keratins, AE1 and CAM5.2, anti-epithelial membrane antigen (EMA), anti-vimentin, anti-S100 protein, and the anti-leukocyte marker PD7/26. Forty-eight of 55 renal cell carcinomas expressed keratins. CAM5.2 stained 46 tumors (84%) and AE1 stained 37 neoplasms (67%). AE1 reacted with two CAM5.2-negative tumors. EMA was expressed by 35 carcinomas (64%), including three of the CAM5.2-negative neoplasms. Therefore, using all three antibodies, 50 neoplasms (91%) expressed antigens of epithelial differentiation. Anti-EMA and AE1 were complementary to each other; the combination stained 46 of the carcinomas, comparable with CAM5.2 alone. Vimentin was expressed by 26 tumors (47%), and S100 was expressed by one. PD7/26 did not stain any of the cases. Vimentin expression correlated with nuclear grade; low nuclear grade neoplasms infrequently expressed vimentin, while the converse was true for high nuclear grade tumors. Keratin expression was related to tumor cell type and histologic pattern, as fewer neoplasms of clear cell type and with a solid pattern expressed keratins. In contrast, all papillary and eight of nine (89%) spindled carcinomas expressed keratins.
View details for Web of Science ID A1988P772000016
View details for PubMedID 2456980
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STUDY OF MURINE T-CELL MIGRATION USING THE THY-1 ALLOTYPIC MARKER - DEMONSTRATION OF ANTIGEN-SPECIFIC HOMING TO LYMPH-NODE GERMINAL-CENTERS
TRANSPLANTATION
1988; 46 (1): 98-104
Abstract
We describe the use of Thy-1 alloantigen as a marker for in vivo T lymphocyte homing studies. Following transfer of 5 x 10(7) peripheral node T cells i.v., 32% of the transferred cells could be recovered in the host lymphoid organs (spleen, lymph nodes, Peyer's patches, and thymus); 11% of the T cells in the lymph nodes were donor derived. The transferred T cells assume the same microenvironmental and immunophenotypic distribution as the host T cells. The transferred T cells are identifiable in peripheral lymph nodes up to 170 days posttransfer, gradually declining in number during this time without evidence of rejection. This Thy-1 transfer technique permits T lymphocyte homing studies to be performed under physiologic conditions without problems of loss of lymphocyte subsets, selective labeling of lymphocyte populations, or long-term marker loss or dilution. We then employ this technique to demonstrate the antigen-directed homing of peripheral T cells to lymph node germinal centers.
View details for Web of Science ID A1988P286800018
View details for PubMedID 2899364
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EXPRESSION OF TAC ANTIGEN BY NON-HODGKINS-LYMPHOMAS
AMERICAN JOURNAL OF CLINICAL PATHOLOGY
1987; 88 (4): 483-485
Abstract
Anti-Tac is a monoclonal antibody that appears to recognize the interleukin-2 receptor. With the use of a frozen-section immunoperoxidase technic, a large series of non-Hodgkin's lymphomas were investigated for the presence of Tac-antigen on neoplastic cells. Approximately one-fourth of cases expressed the Tac antigen, including 27% of B-lineage lymphomas, 6% of the T-lineage lymphomas, and three of four cases of Ki-1-expressing lymphoma. The B-lineage lymphomas with the highest incidence of Tac antigen expression were the large cell lymphomas, both diffuse and follicular, where about one-half of cases expressed the Tac antigen. All major categories of lymphoma expressed Tac except plasma-cytoma/myeloma, small noncleaved cell (Burkitt's and non-Burkitt's), and lymphoblastic malignancies.
View details for Web of Science ID A1987K388100015
View details for PubMedID 2821794
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EXPRESSION OF THE LEU-8 ANTIGEN BY B-CELL LYMPHOMAS
AMERICAN JOURNAL OF CLINICAL PATHOLOGY
1987; 88 (4): 486-490
Abstract
The Leu-8 antigen is found on the surface of many hematologic cells, including many T- and B-lymphocytes. With the use of a frozen-section immunoperoxidase technic, 152 B-cell non-Hodgkin's lymphomas were examined for Leu-8 expression. Of these lymphomas, 53% expressed Leu-8. Subclassification of the lymphomas with the use of the International Working Formulation showed that most small lymphocytic, intermediate lymphocytic, and diffuse large cell lymphomas and about half of diffuse small cleaved, diffuse mixed, and follicular lymphomas expressed Leu-8. In contrast, all 17 cases of small noncleaved cell (Burkitt's) lymphoma and 9 of 10 cases of multiple myeloma/plasmacytoma were Leu-8 negative. These results indicate that Leu-8 is expressed on a wide variety of B-cell lymphomas and that differences in Leu-8 expression may be useful in the diagnostic separation of small lymphocytic lymphoma with plasmacytoid features from multiple myeloma/plasmacytoma, and diffuse large cell lymphoma from Burkitt's lymphoma.
View details for Web of Science ID A1987K388100016
View details for PubMedID 3310610
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A PANEL APPROACH TO THE EVALUATION OF THE SENSITIVITY AND SPECIFICITY OF ANTIBODIES FOR THE DIAGNOSIS OF ROUTINELY PROCESSED HISTOLOGICALLY UNDIFFERENTIATED HUMAN NEOPLASMS
AMERICAN JOURNAL OF CLINICAL PATHOLOGY
1987; 88 (4): 457-462
Abstract
The evaluation of antibodies for diagnostic purposes on routinely processed sections of histologically undiagnosable neoplasms presents special problems. The authors have addressed this problem by constructing a panel of putatively mutually exclusive antibodies and testing it on sections of anaplastic neoplasms. Tissue sections of 120 routinely processed histologically undifferentiated large cell human neoplasms with a histologic differential diagnosis of carcinoma versus lymphoma and/or melanoma were stained with a panel of antibodies composed of monoclonal antikeratin AE1, monoclonal antileukocyte common antigens PD7/26 and 2B11, and rabbit anti-S-100 protein. Only cases not diagnosable by routine morphologic examination were included. PD7/26 and/or 2B11 were positive in 61 cases (supporting lymphoma), AE1 was positive in 17 cases (supporting carcinoma), and anti-S-100 was positive in 25 cases (supporting melanoma). Seventeen neoplasms failed to react with any of the panel antibodies. None of the neoplasms reacted with antibodies directed against two or more different antigens. These results indicate excellent specificity (100%) and good sensitivity (86%) of the panel antibodies on histologically undifferentiated neoplasms. These results are significant on two levels: first, as a test of the panel approach to evaluate antibodies on anaplastic neoplasms, and, second, as a demonstration of the diagnostic utility of the specific panel the authors have employed in such cases.
View details for Web of Science ID A1987K388100009
View details for PubMedID 3661498
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THE SYNCYTIAL VARIANT OF NODULAR SCLEROSING HODGKINS-DISEASE
AMERICAN JOURNAL OF SURGICAL PATHOLOGY
1986; 10 (7): 470-477
Abstract
The histologic and immunologic features of an unusual morphologic expression of nodular sclerosing Hodgkin's disease, which ahs been termed the "syncytial variant," are described. In biopsy material from 18 cases, numerous Reed-Sternberg cell variants were observed in sheets and cohesive clusters, and at least focal evidence of nodular sclerosis was present in each case. The granulocyte antibody anti-Leu M1 reacted with antigenic determinants in Reed-Sternberg cells and atypical variants thereof in 13 of the 18 cases; the lack of staining with antibodies reactive with the leukocyte common (T200) antigen (PD7/26), keratin (AE1), and S100 protein (polyclonal anti-S100) was helpful in excluding non-Hodgkin's lymphoma, carcinoma, and melanoma, respectively. This unusual form of nodular sclerosing Hodgkin's disease is important to recognize, since it may simulate metastatic neoplasms, thymoma, and non-Hodgkin's lymphoma.
View details for Web of Science ID A1986C932300004
View details for PubMedID 2425645
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THE SYNCYTIAL VARIANT OF NODULAR SCLEROSING HODGKINS-DISEASE
WILLIAMS & WILKINS. 1986: A61
View details for Web of Science ID A1986AXX6300377
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MONOCLONAL ANTI-KERATIN (AE1) REACTIVITY IN ROUTINELY PROCESSED TISSUE FROM 166 HUMAN NEOPLASMS
AMERICAN JOURNAL OF CLINICAL PATHOLOGY
1985; 84 (6): 697-704
Abstract
A large number of human neoplasms were tested for their keratin expression in routinely processed tissues by a simple, three-stage immunoperoxidase method using a broadly reactive monoclonal anti-keratin antibody AE1, which recognizes a number of keratin polypeptides distributed in a wide variety of epithelia. All carcinomas, with the exception of hepatocellular, adrenocortical, and basal cell carcinomas and occasional renal cell, pulmonary small-cell, and pulmonary large-cell anaplastic carcinomas, reacted with this antibody irrespective of differentiation, in most instances displaying staining of strong or moderate intensity in the majority of tumor cells. Equivocal results were obtained in some seminomas and dysgerminomas. Malignant melanoma, large-cell lymphoma, Hodgkin's disease, malignant histiocytosis, and stromal mesenchymal elements in all tumors did not show any reactivity with AE1. Even after routine processing, the determinant detected by AE1 is conserved and restricted to epithelial neoplasms. This suggests that AE1 would be valuable in the diagnostic distinction of anaplastic carcinoma from lymphoma and melanoma in routinely processed tissues.
View details for Web of Science ID A1985AVP2300002
View details for PubMedID 2416215
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INVIVO PREVENTION OF THYROID AND PANCREATIC AUTOIMMUNITY IN THE BB RAT BY ANTIBODY TO CLASS-II MAJOR HISTOCOMPATIBILITY COMPLEX GENE-PRODUCTS
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
1985; 82 (19): 6627-6631
Abstract
Evidence is accumulating that the development of insulin-dependent diabetes mellitus involves autoimmune phenomena, both in the human and in the BB rat model. A strong association is observed in both cases with alleles of the class II major histocompatibility complex (MHC). Results of the present study show that autoimmune phenomena, as assessed by the presence of clinical diabetes or histological thyroiditis, are prevented by the injection of monoclonal antibodies to class II gene products in the BB rat. Immunosuppression was specifically obtained with a monoclonal antibody to the murine I-E equivalent, as opposed to the murine I-A equivalent, of the rat major histocompatibility complex. This represents indirect evidence for I-E subregion control of immune responses to islet cell and thyroid antigens in the BB rat model. The frequent occurrence of anaphylactic type deaths in young (1 month old) animals receiving more than six weekly injections of partially purified homologous (rat) monoclonal antibodies to rat class II gene products underscores the potential risks of this type of immunotherapy. The presumed immunologic mechanism (IgE antibody) and its specificity (anti-allotype, anti-idiotype, or anti-impurity) must be clarified to assess the risks and feasibility of this type of therapy.
View details for Web of Science ID A1985ARZ4800056
View details for PubMedID 3901005
View details for PubMedCentralID PMC391263
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THE BEHAVIOR OF GFAP FRACTIONS WITH INSITU POSTMORTEM AUTOLYSIS OF MOUSE SPINAL-CORD
AMER ASSN NEUROPATHOLOGISTS INC. 1984: 311
View details for DOI 10.1097/00005072-198405000-00064
View details for Web of Science ID A1984SS26400061