SLAMF7 and plasma cell myeloma: Elotuzumab is a humanized IgG1 mAb that binds specifically to SLAMF7, also called CS1 (cell surface glycoprotein CD2 subset 1), which is highly expressed on the surface of multiple myeloma cells and on subsets of immune cells including natural killer (NK) cells, NK-like T cells, and a subset of CD8-positive T cells [21].