IFNG and neoplasm: In the initial anti-tumor response after stimulation with α-GalCer/DCs, NKT cells immediately produce large amounts of IFN-γ, which acts on DCs, NK cells, and neutrophils in the innate immune system to eliminate MHC negative tumor target cells and, at the same, also on CD8 cytotoxic T cells and CD4 Th1 cells to kill MHC positive tumor cells, resulting in tumor eradication (Figure 1) (1, 17, 18).