A previous study reported the anti-CD38 antibody, daratumumab, designed to target CD38-expressing myeloma cells, to induce NK cell depletion in patients with multiple myeloma and suggested that the mechanism by which daratumumab reduces the number of NK cells is NK cell fratricide [38] mediated by cross-linking of NK cells via cell-surface CD38. This evidence concerns the gene CD38 and AL amyloidosis.