The number of IFN-γ+ CD8− T cells after infection in wt or C5ar1−/− mice was 5- to 10-fold higher than that of IFN-γ+ NK or NKT cells and 2- to 3-fold higher than that of IFN-γ+ CD8+ T cells (Figures 6B,D). This evidence concerns the gene CD8A and infection.