Analysis of HIV-1 infection of CD4+ T lymphocytes showed that transfection of Hrs and rabankyrin-5 siRNAs reduced the spread of both X4-tropic HIV-192UG029 and R5-tropic HIV-1SF170 viruses from tonsil epithelial cells to CD4+ T lymphocytes by ~55–60% (Fig 10B and 10C, lower panels). This evidence concerns the gene CD4 and HIV-1 infection.