BST2 and Miyoshi myopathy: In this study, we investigated the efficacy of a defucosylated humanized anti-HM1.24 mAb, YB-AHM, in combination with Len against MM cells in bone marrow mononuclear cells (BMMCs) from patients with MM which contain substantial MM cells with relatively smaller numbers of effector cells, and the potential of this combinatory strategy to target clonogenic MM cells.