Translational Mini‐Review Series on B cell subsets in disease. B cells in multiple sclerosis: drivers of disease pathogenesis and Trojan horse for Epstein–Barr virus entry to the central nervous system?

Summary OTHER ARTICLES PUBLISHED IN THIS MINI‐REVIEW SERIES ON B CELL SUBSETS IN DISEASE Transitional B cells in systemic lupus erythematosus and Sjögren's syndrome: clinical implications and effects of B cell‐targeted therapies. Clinical and Experimental Immunology 2012, 167: 7–14. Reconstitution after haematopoietic stem cell transplantation – revelation of B cell developmental pathways and lineage phenotypes. Clinical and Experimental Immunology 2012, 167: 15–25. The recent success of therapies directed at B cells has highlighted their potential as central players in multiple sclerosis (MS) pathogenesis. Exciting new data showed that B cell depletion led to reduced clinical and magnetic resonance imaging (MRI) evidence of disease activity. However, the mechanisms of action remain unknown, but could involve autoantibody production, antigen presentation and/or cytokine production by B cells. Another exciting line of investigation in the field of MS comes from latent infection of memory B cells by Epstein–Barr virus (EBV). These cells are hijacked as ‘Trojan horses’ and ‘smuggle’ the virus into the central nervous system (CNS). Thus, these new anti B cell treatments will also be likely to have anti‐viral effects. We briefly review recent findings in the field of MS pathogenesis, and highlight promising new targets for therapeutic intervention in MS.