J6M0-mcMMAF significantly improved potency and efficacy of ADCC against autologous MM cells. (A) Target cells (MM1Sluc, OPM2, and patient MM cells MM1-2) were labeled with calcein-AM, washed, and incubated with indicated mAbs and NK effector cells in triplicates. Percent lysis was calculated at the end of ADCC assay, based on calcein-AM release. (B) Autologous ADCC activity against CD138⁺ patient cells was determined using PBMCs or CD138-negative cells from the same MM patient at an E:T ratio of 20:1. All data represent mean percent lysis ± standard deviation.