Figure 2.

CD57⁺NKG2C⁺ adaptive NK cells are prevalent in the peripheral blood of AML patients. PBMCs from 30 untreated AML patients and HDs were assessed for adaptive NK cells. A reduced number of AML patients is due to low numbers of NK cells in two untreated blood samples. (A) Gating strategy for adaptive NK cells. First, single cells were selected in a forward scatter area (FSC-A) vs. forward scatter height (FSC-H) plot. Then, living cells were selected as propidium iodide (PI)-negative. Lymphocytes were identified as CD45⁺SSC^low cells in a CD45 vs. side scatter area (SSC-A) dot plot. NK cells were defined as CD3^-NKp80⁺ lymphocytes. Finally, CD57⁺NKG2C⁺ NK cells were identified as adaptive NK cells. (B) GMFI of KIR2DL1/S1/S3/S5 expression on adaptive NK cells vs. total mature CD56^dim NK cells from AML patients (purple squares) and HDs (blue circles). (C) Comparison of % CD57⁺NKG2A⁺ adaptive NK cells from peripheral blood of HDs and AML patients. (D) Percentage of CD57⁺NKG2C⁺ adaptive NK cells in blood of untreated AML patients (n = 24) that tested negative for HCMV (HCMV⁻) vs. positive (HCMV⁺). The red dotted rectangle emphasizes HCMV^– patients with significant percentages of adaptive NK cells. For panels (B–D), red lines represent medians. Mann–Whitney nonparametric U test was used for statistical analysis. ns—p > 0.05; *—p < 0.05; ****—p < 0.0001. A p-value is specified in cases when it is close to 0.05.