In these model systems, we demonstrated that the cytotoxic activity of HLA-restricted, Myeloma-reactive CD4+ and CD8+ CTLs [86] and antibody-dependent cellular cytotoxicity (ADCC) mediated by Daratumumab [87] against MM-cells are significantly diminished in the presence of MSCs or human umbilical vein endothelial cells (HUVECs) without any signs of immune suppression or target antigen downregulation [86,87]. Here, CD8A is linked to Miyoshi myopathy.