The increase in HIV-1 gp120-specific CD4+ and CD8+ T cell responses obtained with the DNA-gp120/MVA-LEO160-gp120 immunization could be of relevant importance, because several studies indicate that the HIV-1-specific cellular response goes some way towards controlling HIV-1 infection, although it fails ultimately to deal with virus infection [65]. Here, CD4 is linked to HIV-1 infection.