Human immunodeficiency virus type 1 infection of U937 cells promotes cell differentiation and a new pathway of viral assembly.
The differentiation of U937 monoblastoid cells after human immunodeficiency virus type 1 (HIV-1) infection was studied using the following approaches: reverse transcriptase activity measurement, immunofluorescence labeling, and electron microscopy. For comparison, uninfected U937 cells were induced to differentiate from monocyte to macrophage by phorbol 12-myristate 13-acetate (PMA) or retinoic acid (RA) treatment. Both infected and drug-treated cells showed important and similar ultrastructural cell modifications, with a phenotype that decreased in monocyte specificity and increased in that of macrophages. When U937 cells were induced to differentiate upon HIV-1 infection, a very different pathway of viral production was observed. Production and accumulation of the virus in a vacuolar compartment of intracytoplasmic origin and escape to the antiviral lysosomal activity could explain virus persistence. This makes the cell system a good model with which to study the relationship between HIV-1 production and cell differentiation.
INSERM U322, Laboratoire des Rétrovirus et Maladies Associées, Marseille, France.
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Pautrat
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Suzan
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Corbeau
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Allasia
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Morel
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Filippi
D015703:Antigens, CD / Q000032:analysis; D002454:Cell Differentiation / Q000187:drug effects; D004721:Endoplasmic Reticulum / Q000648:ultrastructure; D006678:HIV / Q000254:growth & development*; D015658:HIV Infections / Q000382:microbiology / Q000473:pathology*; D006801:Humans; D066298:In Vitro Techniques; D008854:Microscopy, Electron; D009000:Monocytes / Q000382:microbiology*; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014407:Tumor Cells, Cultured; D014617:Vacuoles / Q000648:ultrastructure; D014779:Virus Replication
D015703:Antigens, CD; D012194:RNA-Directed DNA Polymerase; D013755:Tetradecanoylphorbol Acetate