EPITHELIAL UPTAKE AND TRANSPORT OF CELL-FREE HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 AND GP120-COATED MICROPARTICLES

Cell-free human immunodeficiency virus type 1 (HIV-1) can be taken up and released by a monolayer of primary human gingival cells and remain infectious for CD4(+) cells. Virus-sized latex particles covalently c oated with purified native HIV-1 envelope glycoprotein gp120 are also transported through the primary epithelial cells. This process is sign ificantly stimulated by increasing the intracellular cyclic AMP (cAMP) concentration. Inhibition experiments with mannan and alpha-methyl-ma nnopyranoside indicated that mannosyl groups are involved in the inter action between gp120 and gingival cells. An increase of cellular oligo mannosyl receptors by incubation with the mannosidase inhibitor deoxym annojirimycin augmented transcellular transport of the gp120-coated pa rticles. The results suggest that infectious HIV can penetrate gingiva l epithelia by a cAMP-dependent transport mechanism involving interact ion of the lectin-like domain of gp120 and mannosyl residues on glycop roteins on the mucosal surface. Penetration of HIV could be inhibited by soluble glycoconjugates present in oral mucins.