TNFSF13 is a member of the tumor necrosis factor (TNF) ligand family. It is a ligand for TNFRSF17/BCMA. TNFSF13 is lowly expressed in normal tissues, but is elevated in several types of tumors and transformed cell lines. It is mportant for B cell development. TNFSF13 may also play a role in T-independent type II antigen responses and T cell survival, and induce proliferation/survival of non lymphoid cells. It exists as a functional homotrimer. It can bind to two cell surface receptors, BCMA and TACI, which it shares with BAFF to exert downstream T- and B-cell regulatory effects. TNFSF13 also has been demonstrated to bind to proteoglycans on the cell surface.