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 during cell-to-cell adhesion.


METHODS
To investigate the effects of cell-to-cell adhesion on HIV release in association with cytoskeletal elements, chronically HIV-infected T cells were cocultured with different adherent cell lines, cultured on a fibronectin-coated surface, or treated with cytochalasin D. The amount of viral protein released in the culture supernatant and retained inside the cells was monitored by a p24 enzyme-linked immunosorbent assay and Western blotting. For F-actin staining, cells were stained with FITC-labelled phalloidine and examined by immunofluorescence microscopy.


RESULTS
Cocultivation resulted in a reduced amount of virus in the culture supernatant and induced the retention of viral protein inside the infected cells. On adhesion to cells, the F-actin of the infected cells was polarized towards the cell periphery from a diffuse cytoplasmic distribution. Similar data were obtained when the infected cells were treated with cytochalasin D or adhered to fibronectin.


CONCLUSIONS
Cell-to-cell adhesion induced polarization of F-actin, which might facilitate HIV retention inside infected T cells.
Choudhury
S
S
Department of Biodefence and Medical Virology, Kumamoto Uiversity School of Medicine, Japan.
el-Farrash
M A
MA
Kuroda
M J
MJ
Harada
S
S
D000199:Actins / Q000032:analysis; D002448:Cell Adhesion / Q000502:physiology*; D002455:Cell Division; D002460:Cell Line; D018920:Coculture Techniques; D015638:Cytochalasin D / Q000494:pharmacology; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism*; D005353:Fibronectins; D016655:HIV Core Protein p24 / Q000032:analysis; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D013601:T-Lymphocytes / Q000821:virology*; D014779:Virus Replication
D000199:Actins; D005353:Fibronectins; D016655:HIV Core Protein p24; D015638:Cytochalasin D