title: CXCR4/fusin is not a species-specific barrier in murine cells for HIV-1 entry.
abstract: Since some murine cells expressing human CD4 fail to internalize HIV-1, another block was thought to be located at the level of viral entry in addition to CD4. Recently, CXCR4 was shown to function as a coreceptor for T cell line-tropic HIV-1 entry. Here we demonstrated that cells expressing murine CXCR4 and human CD4 fused with cells expressing the env proteins derived from T cell line-tropic HIV-1 and were infected with T cell line-tropic HIV-1 strains. In contrast, the same cells were not infected with chimeric clones constructed by substitution of monocyte- or macrophage-tropic strain-derived env region or V3 region into T cell line-tropic HIV-1, indicating V3 loop of envelope protein is required for murine CXCR4mediated HIV-1 entry. We conclude that murine CXCR4 is not a species specific barrier to the entry of T cell line-tropic HIV-1.
authors.affiliation: Department of Immunology, Research Institute, Osaka Medical Center for Maternal and Child Health, Osaka 590-02, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tachibana
authors.forename: T
authors.initials: T
authors.lastname: Nakajima
authors.forename: A
authors.initials: A
authors.lastname: Sato
authors.forename: K
authors.initials: K
authors.lastname: Igarashi
authors.forename: H
authors.initials: H
authors.lastname: Shida
authors.forename: H
authors.initials: H
authors.lastname: Iizasa
authors.forename: N
authors.initials: N
authors.lastname: Yoshida
authors.forename: O
authors.initials: O
authors.lastname: Yoshie
authors.forename: T
authors.initials: T
authors.lastname: Kishimoto
authors.forename: T
authors.initials: T
authors.lastname: Nagasawa
mesh_terms: D016475:3T3 Cells; D000818:Animals; D015704:CD4 Antigens / Q000096:biosynthesis / Q000502:physiology*; D002118:Calcium / Q000378:metabolism; D002459:Cell Fusion; D017931:DNA Primers; D019204:GTP-Binding Proteins / Q000502:physiology; D015686:Gene Products, env / Q000096:biosynthesis; D015497:HIV-1 / Q000472:pathogenicity / Q000502:physiology*; D006801:Humans; D008565:Membrane Proteins / Q000096:biosynthesis / Q000502:physiology*; D051379:Mice; D016133:Polymerase Chain Reaction; D019718:Receptors, CXCR4; D015728:Receptors, HIV / Q000096:biosynthesis / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013601:T-Lymphocytes; D014162:Transfection
chemical_list: D015704:CD4 Antigens; D017931:DNA Primers; D015686:Gene Products, env; D008565:Membrane Proteins; D019718:Receptors, CXCR4; D015728:Receptors, HIV; D011993:Recombinant Fusion Proteins; D019204:GTP-Binding Proteins; D002118:Calcium