TNFSF13B and autoimmune disease: Four major classes of B-cell targeting drugs have been evaluated for the treatment of autoimmune diseases: neutralization of survival factors BAFF and APRIL [214], killing of B cells using monoclonal antibodies directed to CD19, CD20, and CD22 [215–217], induction of apoptosis using reagents targeting the BCR itself or BCR associated transmembrane signaling proteins such as CD79 [193, 218], and ablation of the formation of ectopic GCs by antibodies against lymphotoxin-β receptor (LTβR) [219].