TNFSF13B and systemic lupus erythematosus: B cells from B-cell chronic lymphocytic leukemia (46), non-Hodgkin's lymphoma (47), rheumatoid arthritis (48), systemic lupus erythematosus (49), and primary Sjogren's syndrome (50) express high levels of BAFF, which rescues them from apoptosis in an autocrine loop.