Differences in granzyme B loading at the bulk level can be explained by the differences observed in the educated population of NK cells. (A) Heatmap representing the granzyme B expression (MFI) using z-score normalization. C1/C1 donors (n = 37), C1/C2 donors (n = 42), and C2/C2 donors (n = 12). (B) Granzyme B expression in the bulk NK population were compared with receptor-negative (Nil) NK cells from the same donor and stratified by the HLA class I background of the donors. (C) Correlation analyses between granzyme B expression in the bulk NK population with the granzyme B loading in the CD57⁺ subset and NKG2A⁺ subset of NK cells. (D) Correlation analysis between granzyme B expression in the bulk NK population and granzyme B levels in the educated NK cells. Each dot represents 1 donor. R is the Pearson coefficient. One-way ANOVA tests followed by Kruskal-Wallis multiple comparison tests were performed in panel B. ∗∗∗∗P < .0001; ∗∗∗P < .001; ∗∗ P < .01; and ∗P < .05.