Given the early IFN-γ response at day 1 of infection, NK (TcRβ- NK1.1+), NKT (TcRβ+ CD1d tetramer+), CD4+ T (TcRβ+ CD4+) and CD8+ T (TcRβ+ CD8+) cell populations were examined in the liver and spleen of MIL-SPpyRE9/DsRed and MIL-RPpyRE9/DsRed infected C57Bl/6 mice. This evidence concerns the gene CD4 and infection.