Cytokine production by NKT cells stimulated with α-GalCer-loaded DCs in vivo. α-GalCer or vehicle-loaded iDCs, IFN/DCs or IL-4/DCs of WT or CD1d^-/- SDDCs were directly injected into the spleen. Six hours (for IL-4 production) or 12 hours (for IFN-γ production) after injection, blood samples were collected and the levels of IFN-γ (▪) and IL-4 (□) in the sera were measured. Each column represents the mean ± SE of 3 independent experiments. Statistical significance was calculated by Student t test (^*P < .05 vs iDCs).