Accelerated central nervous system autoimmunity in BAFF-receptor-deficient mice

B cell activating factor (BAFF) is critical for B cell survival, a function that is mediated by BAFF receptor, (BAFF-R). The role of BAFF (or BAFF-R) in the multiple sclerosis model, experimental autoimmune encephalomyelitis (EAE), was examined using BAFF-R-deficient mice. BAFF-R deficiency resulted in paradoxically increased severity of EAE induced by myelin-oligodendrocyte glycoprotein (MOG) peptide 35–55. Inflammatory foci in BAFF-R-deficient mice comprised increased numbers of activated macrophages expressing BAFF and correlated with increased BAFF secretion. Thus, BAFF-R may be important in EAE pathogenesis, possibly by influencing macrophage function through a mechanism that involves modulation of BAFF expression.