Fig 1: FcεRIγ−NKG2C+CD57+ subset enhanced functional responses to IgG-opsonized targets. (A,B) Percentage of IFNγ−producing cells upon short-term stimulation with Raji target cells, opsonized or not with rituximab anti-CD20 mAb (RTX), was evaluated in freshly isolated peripheral blood FcεRIγ− (grey) and FcεRIγ+ (empty) CD56dim NK cells from HCMV+ individuals (A), or after stratification according to NKG2C and CD57 expression (B). Data are expressed as the fold increase of IFNγ−producing cells in the presence vs. absence of rituximab (RTX/no RTX). Data are representative of 22 independent donors. Bars represent median with interquartile range. p values of pairwise comparisons were calculated by Wilcoxon non-parametric test. (**) = 0.001, (***) < 0.001. (C) Proliferation index of FcεRIγ− (grey) and FcεRIγ+ (empty) CD16+CD56dim NK cell subsets, evaluated as the ratio between cell number fold increase in the presence vs. absence of rituximab (RTX/no RTX). Data are representative of 28 independent donors. (D) Bcl-2 content of FcεRIγ− and FcεRIγ+ CD56dim NK cell subsets. Data are expressed as net mean fluorescence intensity (MFI). Data are representative of 13 HCMV+ healthy donors. (C,D) Bars represent median with interquartile range. p values of pairwise comparisons were calculated by Wilcoxon and Friedman non-parametric tests, as appropriate. For the sake of clarity, only comparisons with NKG2C+CD57+ subsets are reported, after Bonferroni correction. (*) symbol indicates statistical comparison with corresponding FcεRIγ+ subset (FcεRIγ− vs. FcεRIγ+): (**) < 0.005, (***) < 0.00005, (****) < 0.00001; (#) symbol indicates statistical comparison of NKG2C+CD57+ cells with the other subsets belonging to either FcεRIγ− or FcεRIγ+ pools: (#) < 0.05, (##) < 0.005, (###) < 0.0001, (####) < 0.000005, (#####) < 1 × 10−7.