BCMA/TNFRSF17: ProductsB cell maturation protein (BCMA) is a member of the TNF receptor superfamily (TNFRSF17). BCMA is expressed in immune organs and mature Bcell lines. Although some expression has been observed at the cell surface, BCMA appears to be localized to the Golgi compartment. BCMA binding to APRIL or BAFF stimulates IgM production in peripheral blood B cells and increases the survival of cultured B cells. Mature human and mouse BCMA share 86% amino acid sequence identity.