ML NK cells demonstrate prolonged persistence in vivo in patients with relapsed AML. The NK cell multidimensional phenotype was assessed by CyTOF. NK cell subsets were identified by FlowSOM and annotated based on the expression of known ML NK cell markers. (A) Representative composite viSNE demonstrating FlowSOM-gated CD56^dim, CD56^bright, and ML NK cells from donors and patient peripheral blood at 7 to 60 days after NK cell administration. (B) Density viSNE plot of donor NK cells (at screening) and NK cells from patient peripheral blood at day 14 after NK cell administration. (C) Overlay viSNE from panel B. (D) Summary of NK cell populations across time points in patient peripheral blood and bone marrow. (E) Representative histograms of NK cell markers from donor and patient peripheral blood NK cells at day 14 after infusion. (F-G) Summary of median (F) and percentage positive (G) of indicated markers on donor vs patient peripheral blood NK cells at day 14 after infusion. Data include peripheral blood for P-ML002, P-ML005, P-ML009, and P-ML011, along with bone marrow from P-ML008 (as peripheral blood was not available for this donor). For perforin, P-ML011 was excluded due to a technical failure. (D,F-G) Data are presented as the mean and standard error of the mean. Data were tested for normal distribution (Shapiro-Wilk) and then compared using paired t test or Wilcoxon matched-pairs signed rank test. P-values are indicated. CyTOF, cytometry by time of flight; n.s., not significant; viSNE, visual stochastic neighbor embedding.