MCMV infection activates liver iNKT cells in vivo. A, WT mice were infected with MCMV i.p. and αGalCer/CD1d tetramer+ iNKT cells were analyzed for CD25 expression (open histograms) compared to PBS injected controls (shaded histograms) at12 h. Data are representative of 4 independent experiments of 2-3 mice per group. B, Time course of the mean fluorescence intensity (MFI) of CD25 expression after infection. Time 0 is the average MFI of PBS injected controls. Average MFI of iNKT cells in one of 4 independent experiments. Error bars, SEM (n=3 for each time point). C, At the indicated times, liver mononuclear cells were stained for intracellular IFN-γ and the data were gated for αGalCer/CD1d tetramer positive iNKT cells. Numbers represent the percentage of IFN-γ+ cells in the iNKT cell population. D, Time course of the MCMV activated iNKT cell IFNγ response. MFI of intracellular IFN-γ (open histograms) were compared to isotype controls (shaded histograms). Far left panels represent the iNKT cell response 2 h after i.p. injection of αGalCer. Results are representative of 3 independent experiments of 3-5 mice per group.