CS1, a SLAM family receptor involved in immune regulation, is a therapeutic target in multiple myeloma.

Signaling lymphocytic activation molecule (SLAM) family receptors have been implicated in normal immunity, immunodeficiencies and autoimmunity. CS1 (also known as CRACC, CD319 and SLAMF7) is a member of the SLAM family expressed on several normal hematopoietic cell types. It is also highly and nearly universally expressed on multiple myeloma (MM) cells. This review focuses on the biology of CS1, both in normal hematopoietic cells and in MM cells. It also discusses the preclinical and clinical data on the use of a humanized anti-CS1 monoclonal antibody, elotuzumab, for the treatment of MM. Based on current knowledge, CS1 is a compelling new target for the treatment of MM.