Neuroinflammation PET imaging: Current opinion and future directions.
Journal of nuclear medicine : official publication, Society of Nuclear Medicine
Neuroinflammation is a pathological hallmark of numerous neurologic diseases. Positron emission tomography (PET) imaging enables a non-invasive means to investigate, quantify, and track the spatiotemporal dynamics of various immune cells in living subjects. Translocator protein 18 kDa (TSPO)-PET is a technique for detecting glial activation that has yielded valuable clinical data linking neuroinflammation to cognitive decline in neurodegenerative diseases and has also been used preliminarily as a therapy monitoring tool. However, considerable limitations of TSPO-PET have prompted identification of other more cell-specific and functionally relevant biomarkers. This review analyzes the clinical potential of available and emerging PET biomarkers of innate and adaptive immune responses, with mention of exciting future directions for the field.
View details for DOI 10.2967/jnumed.119.229443
View details for PubMedID 32620705
Development of a CD19 PET tracer for detecting B cells in a mouse model of multiple sclerosis.
Journal of neuroinflammation
2020; 17 (1): 275
B cells play a central role in multiple sclerosis (MS) through production of injurious antibodies, secretion of pro-inflammatory cytokines, and antigen presentation. The therapeutic success of monoclonal antibodies (mAbs) targeting B cells in some but not all individuals suffering from MS highlights the need for a method to stratify patients and monitor response to treatments in real-time. Herein, we describe the development of the first CD19 positron emission tomography (PET) tracer, and its evaluation in a rodent model of MS, experimental autoimmune encephalomyelitis (EAE).Female C57BL/6 J mice were induced with EAE through immunization with myelin oligodendrocyte glycoprotein (MOG1-125). PET imaging of naïve and EAE mice was performed 19 h after administration of [64Cu]CD19-mAb. Thereafter, radioactivity in organs of interest was determined by gamma counting, followed by ex vivo autoradiography of central nervous system (CNS) tissues. Anti-CD45R (B220) immunostaining of brain tissue from EAE and naïve mice was also conducted.Radiolabelling of DOTA-conjugated CD19-mAb with 64Cu was achieved with a radiochemical purity of 99% and molar activity of 2 GBq/μmol. Quantitation of CD19 PET images revealed significantly higher tracer binding in whole brain of EAE compared to naïve mice (2.02 ± 0.092 vs. 1.68 ± 0.06 percentage of injected dose per gram, % ID/g, p = 0.0173). PET findings were confirmed by ex vivo gamma counting of perfused brain tissue (0.22 ± 0.020 vs. 0.12 ± 0.003 % ID/g, p = 0.0010). Moreover, ex vivo autoradiography of brain sections corresponded with PET imaging results and the spatial distribution of B cells observed in B220 immunohistochemistry-providing further evidence that [64Cu]CD19-mAb enables visualization of B cell infiltration into the CNS of EAE mice.CD19-PET imaging can be used to detect elevated levels of B cells in the CNS of EAE mice, and has the potential to impact the way we study, monitor, and treat clinical MS.
View details for DOI 10.1186/s12974-020-01880-8
View details for PubMedID 32948198
Radiolabeling and pre-clinical evaluation of a first-in-class CD19 PET Tracer for imaging B cells in multiple sclerosis
SOC NUCLEAR MEDICINE INC. 2019
View details for Web of Science ID 000473116800129