Expression Levels of B Cell Receptor (BCR) Signaling Pathway Factors are Associated with Conversion from Clinically Isolated Syndrome to Multiple Sclerosis

Objective: We have previously shown altered blood B cells in the first attack blood samples of clinically isolated syndrome (CIS) patients, who converted to multiple sclerosis (MS). Our aim was to investigate levels of B cell receptor (BCR)-associated genes expression in converting CIS (CIS-c) and non-converting CIS patients (CISnc) with a 5-year follow-up. Methods: Seven CIS-c patients, 12 CIS-nc patients and 10 agesex matched healthy donors were enrolled in this study. RNA was extracted from frozen peripheral blood cells of subjects that were obtained in the first attack using a RNA isolation kit. Expression levels of B-cell adaptor protein with ankyrin repeats 1 (BANK1), B lymphocyte kinase (BLK) and Fc receptor-like protein 2 (FCRL2) genes were evaluated samples by real-time polymerase chain reaction (RT-PCR). Results: CIS-nc patients showed elevated BANK1, BLK and FCRL2 gene expression levels as compared to CIS-c patients and healthy controls. Conclusions: Expression levels of the genes that inhibit BCR signaling are increased in CIS-nc, suggesting that inhibiting exaggerated B cell response by optimization of B cell proliferation may prevent the progression of clinically isolated syndrome to MS.