Herein, we use a human mixed cell suspension model to directly assess whether the susceptibility of FRT CD4+ T cells and CD14+ macrophages to HIV-1 infection is altered in the years following menopause and test the hypothesis that greater CD4+ T cell CCR5 expression following menopause results in increased HIV-1 infection susceptibility in the FRT. This evidence concerns the gene CD4 and HIV-1 infection.