Daratumumab, an anti-CD38 mAb initially developed to target tumoral plasma cells in multiple myeloma (137) is also effective in inhibiting clinical activity of antibody-mediated autoimmune diseases, such as autoimmune cytopenia following hematopoietic stem cell transplantation (138) or systemic lupus erythematosus (SLE) (139). The gene discussed is CD38; the disease is systemic lupus erythematosus.