IFNG and infection: Based on our findings that Rag1−/− mice lacking all T cells, including NKT cells, were still able to control N. caninum infections (Fig. 3) and produce immediate IFNγ (Fig. 5A), we hypothesized that infections in Rag2−/− γC−/− mice lacking NK cells would result in uncontrolled proliferation and the loss if IFNγ production.