Monocyte-mediated lysis of HIV-infected tumor cells.
Peripheral blood monocytes (PBM) can selectively lyse malignant or virus-infected cells. We investigated the effects of target cell infection with HIV-1 on PBM cytolytic function. Cytokine-activated PBM lysed uninfected, HSV-1-infected or vaccinia virus-infected tumor cells, but did not lyse the same cell lines when infected with the human immunodeficiency virus type 1 (HIV-1). HIV did not impair PBM viability, and actinomycin D (Act D) pretreatment of HIV-infected target cells restored their susceptibility to PBM-mediated lysis. Either antibody to CD4 (Leu3a) or a recombinant vaccinia virus that induces expression of the HIV envelope protein, also inhibited target cell lysis by PBM. These studies indicate that CD4 can function as a mediator of PBM cytolytic function, and that target cell expression of the HIV-1 envelope protein may inhibit monocyte-mediated antitumor responses.
Cancer Research Institute, University of California, San Francisco 94143-0128.
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Debs
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Krowka
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Stites
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Brunette
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Düzgünes
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Philip
D000911:Antibodies, Monoclonal / Q000276:immunology; D015704:CD4 Antigens / Q000502:physiology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000382:microbiology; D003602:Cytotoxicity, Immunologic; D003609:Dactinomycin / Q000494:pharmacology; D005455:Fluorescent Antibody Technique; D015699:HIV Envelope Protein gp120 / Q000276:immunology; D015497:HIV-1 / Q000187:drug effects / Q000276:immunology / Q000502:physiology*; D006801:Humans; D007372:Interferons / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000187:drug effects; D009000:Monocytes / Q000276:immunology* / Q000382:microbiology; D014407:Tumor Cells, Cultured / Q000276:immunology / Q000382:microbiology*
D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D015699:HIV Envelope Protein gp120; D003609:Dactinomycin; D007372:Interferons