B-cell MTNFRSF17, or B-cell maturation antigen (BCMA), is a cell-surface receptor belonging to the tumor necrosis factor receptor superfamily. It is selectively and consistently expressed on plasma cells and mature B lymphocytes. BCMA is a critical survival receptor, binding to its ligands APRIL and BAFF to promote plasma cell longevity, proliferation, and disease progression.aturation Antigen (BCMA; also known as TNFRSF17 or CD269), a member of the tumor necrosis factor receptor superfamily. BCMA is selectively and highly expressed on the surface of malignant plasma cells in multiple myeloma and normal plasma cells, with minimal expression on other tissues. Its expression is nearly universal in myeloma, making it an ideal therapeutic target. The natural ligands for BCMA are BAFF (BLyS) and APRIL, which promote plasma cell survival and proliferation.