Intracellular expression of cytotoxic effector molecules and expression of exhaustion markers in chronically activated iNKT cells. (A) Representative histograms of IFN-γ or IL-4 expression based on CD161 and HLA-II expression (left) and a summary of the ratio of the frequency of IFN-γ to IL-4–positive cells based on CD161 and HLA-II expression (right; n = 7). (B) Mean fluorescence intensity of expression of perforin (Per), granzyme B (Gzm B), and granulysin based on CD161 and HLA-II expression in in vitro expanded iNKT cells (n = 7). (C) Frequency of expression of Tim-3, PD-1, and NKG2D based on CD161 and HLA-II expression in in vitro expanded iNKT cells (n = 7). Means ± standard error of the mean (A-C). *P = .05-.01; **P = .009-.001; ****P < .0001.