RETENTION OF HIV-1 INSIDE INFECTED MOLT-4 CELLS IN ASSOCIATION WITH ADHESION-INDUCED CYTOSKELETON REORGANIZATION

Objective: To study the mechanism of the suppression of HIV release du ring cell-to-cell adhesion. Design and methods: To investigate the eff ects of cell-to-cell adhesion on HIV release in association with cytos keletal elements, chronically HIV-infected T cells were cocultured wit h different adherent cell lines, cultured on a fibronectin-coated surf ace, or treated with cytochalasin D. The amount of viral protein relea sed in the culture supernatant and retained inside the cells was monit ored by a p24 enzyme-linked immunos-orbent assay and Western blotting. For F-actin staining, cells were stained with FITC-labelled phalloidi ne and examined by immunofluorescence microscopy. Results: Cocultivati on resulted in a reduced amount of virus in the culture supernatant an d induced the retention of viral protein inside the infected cells. On adhesion to cells, the F-actin of the infected cells was polarized to wards the cell periphery from a diffuse cytoplasmic distribution. Simi lar data were obtained when the infected cells were treated with cytoc halasin D or adhered to fibronectin. Conclusion: Cell-to-cell adhesion induced polarization of F-actin, which might facilitate HIV retention inside infected T cells.