Human NK cells exhibit an activated phenotype in patients after HSCT. (A) Characteristics of patients who received T-cell–replete haploidentical allogeneic HSCT after a reduced-intensity conditioning. (B) Proportion of NK and T cells within total live PBMCs from healthy donors vs patients after HSCT. (C) Frequency of CD69 on NK- and T-cell PBMCs from healthy donors vs patients after HSCT. (D) Frequency of PD-1 on NK- and T-cell PBMCs from healthy donors vs patients after HSCT. (E) Frequency of Ki67 on NK- and T-cell PBMCs from healthy donors vs patients after HSCT. Means ± standard error of the mean are shown for 3 healthy donors and 4 HSCT donors. *P < .05; ***P < .001, by 1-way ANOVA with Tukey post hoc test.