Figure 1.

Effector responses of adaptive natural killer (NK) cells against target cells are amplified by cytokine costimulation. (A) Representative staining of interferon (IFN)-γ gated on conventional NKG2C⁻ or adaptive NKG2C⁺ NK cells after 24 h culture in the absence or presence of interleukin (IL)-12 + 18. (B) Summary of frequencies of IFN-γ⁺ cells. Symbols indicate individual donors, and red lines indicate median (n = 9). (C) Representative staining of IFN-γ gated on adaptive NKG2C⁺ NK cells after 6 h culture either alone or with K562/HLA-E target cells in the absence or presence of IL-12 + 18. (D) Summary of frequencies of IFN-γ⁺ cells and (E) summary of geometric mean fluorescence intensity (geoMFI) of IFN-γ in IFN-γ⁺ cells, n = 17 donors. (F) Summary of IFN-γ protein concentrations in the supernatant of cocultures, n = 7 donors. (G) Representative staining of tumor necrosis factor (TNF) gated on adaptive NKG2C⁺ NK cells after 6 h culture either alone or with K562/HLA-E target cells in the absence or presence of IL-12 + 18. (H) Summary of frequencies of TNF⁺ cells and (I) summary of geoMFI of TNF in TNF⁺ cells, n = 17 donors. (J) Summary of TNF protein concentrations in the supernatant of cocultures, n = 7 donors. Connected symbols indicate individual donors, and red lines indicate median. All statistical analyses performed with one-tailed Wilcoxon matched-pairs test. *p < 0.05, **p < 0.01, ***p < 0.001, and ****p < 0.0001.