Functional properties resembling those of adaptive NK cells in patients with GATA2 mutation. PBMCs from healthy donors, CMV seronegative (n = 3) or seropositive selected for individuals with sizeable expansions of adaptive NK cells (n = 6), as well as patients (n = 4 or n = 8) and asymptomatic carriers (n = 2; asymptomatic carriers 1 and 2) with heterozygous GATA2 mutations were rested overnight, stimulated, and examined for functional responses by flow cytometry. (A) Rested PBMCs were incubated for 24 hours in cell culture medium only or in medium supplemented with IL-12 (10 ng/mL) and IL-18 (100 ng/mL). Histograms show intracellular IFN-γ expression after culture in medium only (filled histograms) or IL-12 and IL-18 (open histograms). Graphs depict frequencies of CD3⁻CD56^dim NK cells expressing IFN-γ. Data from patients 2, 4, 6, and 8 are depicted. (B-D) PBMCs were cocultured with P815 target cells in the presence of 2 μg/mL isotype control IgG (cIgG; filled histograms) or anti-human CD16 (CD16; open histogram) monoclonal antibodies for 6 hours followed by flow cytometric analysis. Histograms show expression of (B) surface CD107a as well as intracellular (C) IFN-γ or (D) TNF in gated CD3⁻CD56^dim NK cells. Graphs depict frequencies of CD3⁻CD56^dim NK cells expressing the indicated functional marker. Data from patients 1, 2, 3, 4, 6, 7, 8, and 9 are depicted.