AAVS1KO/CD38-CAR NK cells display enhanced cytotoxicity and metabolism. CD38-CAR NK cells were tested against CD38-expressing AML, MM, and BL. (A) CD38-CAR NK-cell killing of CD38-expressing cell lines (n = 3; mean ± SD). P values were calculated using a 2-way ANOVA; ∗P < .05; ∗∗P < .01; ∗∗∗P = .001; ∗∗∗∗P < .0001. (B) Oxygen consumption rate (OCR) for CD38-CAR NK cells. (C) Glycolytic capacity, measured by the extracellular acidification rate (ECAR), observed in CD38-CAR NK cells. (D) Spare respiratory capacity, a measure of the cell's ability to produce adenosine triphosphate (ATP) in response to stress, measured in CAR NK cells. (E) CAR NK-cell maximal respiration rates compared with WT.