Complement-mediated cytotoxicity and ADCC using patient serum. (A-B) — indicates BCMA-293 cells; –, vector-293 cells; (A-D) ♦, patient 1; ▪, patient 2. (A) Complement-mediated cytotoxicity of post-DLI patient serum against BCMA-293 or vector-293 target cells. (B) ADCC mediated by post-DLI patient serum against BCMA-293 or vector-293 target cells. (C-D) ADCC mediated by post-DLI patient serum against BCMA-positive multiple myeloma (MM) cells. Serum from 2 healthy donors (• and ▴) was also tested at 1:10 dilution.