The in vivo cytotoxicity of CD8+ T cells is not dependent on IFN-γ as recently shown in a murine model of prime-boosting using DNA and recombinant adenoviruses against Chagas disease; here, protection against the disease was reduced in IFN-γ−/− mice even in the presence of specific CTLs [21]. This evidence concerns the gene CD8A and Chagas disease.