CD4+ T cell specific (LckcreIL-4Rα−/lox) IL-4Rα−/− mice are more resistant than global IL-4Rα−/− mice to infection with L. major, indicating that in the absence of a polarized Th2 response, there is a role for an IL-4/IL-13 responsive non-CD4+ T cell in early resistance to infection [9]. This evidence concerns the gene CD4 and infection.