These could play a role in the protection mediated by the vaccine regimens presented here: although depletion of CD4+ and CD8+ T cells did not abrogate the protective effect of the Ad-M CSP vaccine, this may be because anti-CSP antibodies played the principal role in protection, as evident from the strong correlation with time to reach 1% parasitemia (Fig. 3Bi). This evidence concerns the gene CD4 and parasitic infectious disease.