IFN-γ production from freshly isolated cells and cultured NK cell subsets. (A) Freshly isolated NK cells (DX5⁺/CD3^-, ▪) and T cells (DX5^-/CD3⁺, □) were stimulated with the indicated cytokines for 18 hours and the supernatants analyzed for IFN-γ production. (B) Freshly sorted NK cells (DX5⁺/CD3^-, □) and NKT cells (DX5⁺/CD3⁺, ▪) were cultured in IL-2 for 3 days to expand and then were stimulated with the cytokines for 6 hours and supernatants analyzed for IFN-γ. The data are representative of 3 separate experiments.