Innate responses of B cells.

In this review, we describe the non-antibody-mediated functions of B cells within the immune system. In addition to antibody production, B cells also present antigen to T cells, programme T cell differentiation and regulate effector T cell responses and much of this is mediated by the cytokines they make. We focus on the potential of B cells to perform these functions simply as a result of activation via 'innate' receptors (e.g. Toll-like receptors) and often independently of BCR ligation. We feel an appreciation of these broad and often antigen-nonspecific functions is important at a time when there is an increasing use of B cell depletion as a therapy for autoimmune disease.