Divergent changes in mitochondrial morphology accompany activation of NKBr vs NKDim cells. (A-D) Freshly sorted NKDim and NKBr cells were stained with Mitotracker green and TMRM and imaged by confocal microscopy (0 hours). Cytokines were added to the medium as indicated in the figures, and images were taken every 6 hours. . (C-D) Mitochondrial fragmentation (C) and total TMRM intensity (D) at different time points for NKBr and NKDim cells. Circles are technical replicates from 3 HDs. (E) Primed or activated NKBr and NKDim cells were cultured for 18 hours ± Mdivi-1 (25 μM). Expression of IFN-γ was monitored by fluorescence-activated cell sorting; data from 3 independent experiments with at least 2 donors each). P > .05 was considered not significant (ns). *P < .05, **P < .01, ***P < .001, ****P < .0001 using 1-way analysis of variance with Tukey’s correction.