Unexpanded g-NK cells demonstrate superior ADCC activity in vitro. Comparison of the cytotoxicity of freshly isolated (unexpanded) g-NK and cNK cells against MM.1S cells at multiple NK:myeloma cell ratios (0.5X, 1X, 2.5X, and 5X) with daratumumab (A), elotuzumab (B), or no mAb present (C) (n = 16 unique donors). To compare cytotoxicity against MM cells between unexpanded g-NK and cNK cells, a maximum likelihood linear mixed model was built that included main effects for NK cell category (g-NK vs cNK), antibody category (daratumumab, elotuzumab, or no mAb), and E:T ratio (0.5X, 1X, 2.5X, 5X) as well as interaction effects of NK cell category × antibody category and NK cell category × E:T ratio. Bonferroni post hoc analyses were performed to determine the locations of the significant effects for NK cell category (ie, at what E:T ratios or antibody conditions the g-NK effects were present). Values are mean ± standard error of the mean (SEM). *P < .05; ***P < .001. Dara, daratumumab; Elo, elotuzumab; ns, not significant.