B cells clearly play an essential role in the pathogenesis of SLE since they produce autoantibodies. Clinical observations support the contention that intervening in the production of autoantibodies by the B lymphocyte will be effective therapy. Current approved therapy for B-cell non-Hodgkin's lymphoma includes anti-CD20. The results of anti-CD20 administration in SLE are anticipated to be similar to those in lymphoma patients. The current proposal explores the mechanisms and applicability of B-cell depletion as a potential treatment for SLE.