Fingolimod therapy modulates circulating B cell composition, increases B regulatory subsets and production of IL-10 and TGFβ in patients with Multiple Sclerosis. (June 2016)

• Record Type: Journal Article
• Authors: Blumenfeld, Shiri; Staun-Ram, Elsebeth; Miller, Ariel
• Is Part Of: Journal of autoimmunity. Volume 70(2016)
• Page Start: 40
• Page End: 51
• Publication Date: 2016-06
• Subjects: Autoimmunity -- B cell subsets -- Cytokine -- Fingolimod -- Multiple sclerosis -- Regulatory cells; Autoimmunity -- Periodicals; Autoimmune diseases -- Periodicals; Autoantibodies -- Periodicals; Autoimmune Diseases -- Periodicals; Auto-immunité -- Périodiques; Maladies auto-immunes -- Périodiques; Electronic journals; 616.978005
• DOI: 10.1016/j.jaut.2016.03.012
• Languages: English
• ISSNs: 0896-8411

Abstract

Abstract: Fingolimod, an oral therapeutic agent approved for patients with relapsing-remitting Multiple Sclerosis (MS), has been shown to prevent lymphocyte egress from secondary lymphoid tissues; however the specific drug effect on B cells in fingolimod-treated patients remains to be fully elucidated. We present here a comprehensive analysis on the proportions of B cell subsets in the periphery, and the levels of activation, functional surface markers and cytokine profile of B cells in MS patients, following initiation of fingolimod therapy, using flow cytometry and cytokine bead array. Fingolimod therapy increased the ratio of naïve to memory cells, elevated the percentage of plasma cells and highly increased the proportion of transitional B cells as well as additional regulatory subsets, including: IL10 +, CD25 + and CD5 + B cells. The percentage of activated CD69 + cells was highly elevated in the remaining circulating B cells, which produced increased levels of IL10, TGFβ, IL6, IL4, LTα, TNFα and IFNγ cytokines, with an overall increased ratio of TGFβ to pro-inflammatory cytokines. Furthermore, fingolimod therapy reduced ICAM-1 + cells, suggesting a possible reduction in antigen-presenting capacity. Phosphorylated-fingolimod was shown in vitro to reduce S1PR1 RNA and protein, to slightly increase viability and to activate anti-apoptotic Bcl2 in transformed B cells of patients with MS. In conclusion, fingolimod therapy modulates significantly the composition of circulating B cells, promoting regulatory subsets and an anti-inflammatory cytokine repertoire. Highlights: Fingolimod modulates B cell composition and functional markers in patients with MS. Fingolimod reduces memory B cells, while increases transitional and plasma cells. Fingolimod elevates B regulatory subsets, such as IL10, CD25 and CD5 B cells. Remaining circulating B cells are activated, showing increased cytokine production. Fingolimod promotes elevated ratios of TGFβ to pro-inflammatory cytokines.