CD20+inflammatory T-cells are present in blood and brain of multiple sclerosis patients and can be selectively targeted for apoptotic elimination.
BACKGROUND
A subset of T-cells expresses the B-cell marker CD20 and in rheumatoid arthritis secretes Interleukin (IL)-17. IL-17 secreting T-cells (Th17) have also been implicated in the inflammatory response in the central nervous system in multiple sclerosis (MS) and may be a potential target for elimination by biologic therapeutics. ScFvRit:sFasL comprises of a rituximab-derived antibody fragment scFvRit genetically fused to human soluble FasL that specifically eliminated T-cells.


OBJECTIVE
To determine the presence and phenotype of CD20+T-cells in blood and brain of MS patients. Second, to determine whether scFvRit:sFasL can selectively eliminate CD20+T-cells. After CD20-selective binding, scFvRit:sFasL is designed to trigger FasL-mediated activation-induced cell death of T-cells, but not B-cells.


METHODS
Flow cytometry and immunohistochemistry were used to screen for CD20+inflammatory T-cells in MS blood and brain tissue. ScFvRit:sFasL pro-apoptotic activity was evaluated by Annexin-V/PI staining followed by flow cytometry assessment.


RESULTS
Peripheral blood (n=11) and chronic but not active lesions of MS patient brains (n=5) contained CD20+inflammatory T-cells. Activated CD20+T-cells were predominantly CD4+and secreted both IL-17 and INF-γ. ScFvRit:sFasL triggered CD20-restricted FasL-mediated activation-induced cell death in peripheral blood CD20+T-cells, but not CD20+B-cells.


CONCLUSIONS
CD20+inflammatory T-cells are present in blood and chronic brain lesions of MS patients. ScFvRit:sFasL selectively eliminated CD20+T-cells and may eliminate pathogenic T-cells without B-cell depletion.
University of Exeter Medical School & Neurology Department, Royal Devon and Exeter Hospital, University of Exeter, Devon, UK.
Janet E
JE
Holley
Department of Surgery, University Medical Centre, University of Groningen, Groningen, Netherlands.
Edwin
E
Bremer
University of Exeter Medical School & Neurology Department, Royal Devon and Exeter Hospital, University of Exeter, Devon, UK.
Alexandra C
AC
Kendall
Department of Surgery, University Medical Centre, University of Groningen, Groningen, Netherlands.
Marco
M
de Bruyn
Department of Surgery, University Medical Centre, University of Groningen, Groningen, Netherlands.
Wijnand
W
Helfrich
University of Exeter Medical School & Neurology Department, Royal Devon and Exeter Hospital, University of Exeter, Devon, UK.
Joanna M
JM
Tarr
NeuroResource, UCL Institute of Neurology, London, UK.
Jia
J
Newcombe
University of Exeter Medical School & Neurology Department, Royal Devon and Exeter Hospital, University of Exeter, Devon, UK.
Nicholas J
NJ
Gutowski
University of Exeter Medical School & Neurology Department, Royal Devon and Exeter Hospital, University of Exeter, Devon, UK. Electronic address: P.Eggleton@exeter.ac.uk.
Paul
P
Eggleton
D000328:Adult; D018951:Antigens, CD20 / Q000276:immunology*; D017209:Apoptosis / Q000187:drug effects* / Q000276:immunology; D001921:Brain / Q000187:drug effects / Q000276:immunology*; D002478:Cells, Cultured; D016503:Drug Delivery Systems / Q000379:methods; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000097:blood / Q000188:drug therapy / Q000276:immunology*; D000069283:Rituximab / Q000627:therapeutic use*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D016896:Treatment Outcome; D055815:Young Adult
D018951:Antigens, CD20; D007166:Immunosuppressive Agents; D000069283:Rituximab
Biologics; Chronic lesions; Human tissue; Interleukin-17; T-cells