title: Factors secreted by human T lymphotropic virus type I (HTLV-I)-infected cells can enhance or inhibit replication of HIV-1 in HTLV-I-uninfected cells: implications for in vivo coinfection with HTLV-I and HIV-1.
abstract: It remains controversial whether human T lymphotropic virus type I (HTLV-I) coinfection leads to more rapid progression of human immunodeficiency virus (HIV) disease in dually infected individuals. To investigate whether HTLV-I infection of certain cells can modulate HIV-1 infection of surrounding cells, primary CD4(+) T cells were treated with cell-free supernatants from HTLV-I-infected MT-2 cell cultures. The primary CD4+ T cells became resistant to macrophage (M)-tropic HIV-1 but highly susceptible to T cell (T)-tropic HIV-1. The CC chemokines RANTES (regulated on activation, normal T cell expressed and secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta in the MT-2 cell supernatants were identified as the major suppressive factors for M-tropic HIV-1 as well as the enhancers of T-tropic HIV-1 infection, whereas soluble Tax protein increased susceptibility to both M- and T-tropic HIV-1. The effect of Tax or CC chemokines on T-tropic HIV-1 was mediated, at least in part, by increasing HIV Env-mediated fusogenicity. Our data suggest that the net effect of HTLV-I coinfection in HIV-infected individuals favors the transition from M- to T-tropic HIV phenotype, which is generally indicative of progressive HIV disease.
authors.affiliation: Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA. hmoriuchi@atlas.niaid.nih.gov
authors.forename: H
authors.initials: H
authors.lastname: Moriuchi
authors.forename: M
authors.initials: M
authors.lastname: Moriuchi
authors.forename: A S
authors.initials: AS
authors.lastname: Fauci
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000821:virology*; D002460:Cell Line; D018925:Chemokines / Q000276:immunology / Q000494:pharmacology; D016356:Gene Products, tax / Q000276:immunology / Q000494:pharmacology; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000502:physiology*; D015490:HTLV-I Infections / Q000276:immunology*; D015368:Human T-lymphotropic virus 1 / Q000502:physiology*; D006801:Humans; D019707:Receptors, Chemokine / Q000276:immunology; D014779:Virus Replication / Q000187:drug effects / Q000276:immunology*
chemical_list: D018925:Chemokines; D016356:Gene Products, tax; D019707:Receptors, Chemokine