Parameters of human immunodeficiency virus infection of human cervical tissue and inhibition by vaginal virucides

Heterosexual transmission of human immunodeficiency virus (HIV) is the most frequent mode of infection worldwide. However, the immediate events betwee n exposure to infectious virus and establishment of infection are still poo rly understood. This study investigates parameters of HIV infection of huma n female genital tissue in vitro using an explant culture model. In particu lar, we investigated the role of the epithelium and virucidal agents in pro tection against HN infection. We have demonstrated that the major target ce lls of infection reside below the genital epithelium, and thus HIV must cro ss this barrier to establish infection. Immune activation enhanced HIV infe ction of such subepithelial cells. Furthermore, our data suggest that genit al epithelial cells were not susceptible to HIV infection, appear to play n o part in the transfer of infectious virus across the epithelium, and thus may provide a barrier to infection. In addition, experiments using a panel of virucidal agents demonstrated differential efficiency to block HIV infec tion of subepithelial cells from partial to complete inhibition. This is th e first demonstration that virucidal agents designed for topical vaginal us e block HIV infection of genital tissue, Such agents have major implication s for world health, as they will provide women with a mechanism of personal and covert protection from HIV infection.