title: Changes in and discrepancies between cell tropisms and coreceptor uses of human immunodeficiency virus type 1 induced by single point mutations at the V3 tip of the env protein.
abstract: We examined the effect of amino acid substitutions of the GPGR (glycine-proline-glycine-arginine) tip sequence at the V3 domain of the Env protein of human immunodeficiency virus type 1 (HIV-1) on its cell tropism and coreceptor use. We changed the GPGR sequence of a T-cell line (T)- and macrophage (M)-tropic (R5-R3-X4) HIV-1 strain, GUN-1wt, to GA(alanine)GR (the resulting mutant was designated GUN-1/A), GL(leucine)GR (GUN-1/L), GP(proline)GR (GUN-1/P), GR(arginine)GR (GUN-1/R), GS(serine)GR (GUN-1/S), or GT(threonine)GR (GUN-1/T). GUN-1/A, GUN-1/S, and GUN-1/T mutants infected brain-derived cells such as a CD4-transduced glioma cell line, U87/CD4, and a brain-derived primary cell strain, BT-20/N, as well as T-cell lines in a CD4-dependent manner, although the plating of these mutants onto macrophages was inhibited. GUN-1/L, GUN-1/P, and GUN-1/R mutants showed both T- and M-tropism, but did not plate onto the brain-derived cells. A CCR3, CCR5, CCR8, or CXCR4 gene was introduced into a CD4-positive glioma cell line, NP-2/CD4, which demonstrated complete resistance to various HIV-1 strains. Not only HIV-1 strains, which were infectious to macrophages, such as GUN-1wt, GUN-1v, GUN-1/L, and GUN-1/P, but also an HIV-1 strain, GUN-1v, which was hardly infectious to macrophages, grew well in NP-2/CD4 cells expressing CCR3 or CCR5. However, the M-tropic GUN-1/R mutant could not efficiently use CCR5 nor CCR3. No point mutants, except GUN-1/L, grew well in NP-2/CD4 cells expressing CCR8. These findings indicate that the cell tropism of HIV-1 to macrophages and brain-derived cells and their use of the coreceptors were markedly, though not always concomitantly, affected by the tip sequence of the V3 domain.
authors.affiliation: Department of Hygiene and Virology, Gunma University School of Medicine, Showa-machi, Maebashi, Gunma, 371-8511, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Shimizu
authors.forename: Y
authors.initials: Y
authors.lastname: Haraguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Takeuchi
authors.forename: Y
authors.initials: Y
authors.lastname: Soda
authors.forename: K
authors.initials: K
authors.lastname: Kanbe
authors.forename: H
authors.initials: H
authors.lastname: Hoshino
mesh_terms: D001921:Brain / Q000166:cytology / Q000821:virology*; D015704:CD4 Antigens / Q000502:physiology; D002460:Cell Line; D002478:Cells, Cultured; D015488:HIV Antigens / Q000378:metabolism; D015699:HIV Envelope Protein gp120 / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D015497:HIV-1 / Q000235:genetics / Q000502:physiology*; D006801:Humans; D008264:Macrophages / Q000821:virology*; D016297:Mutagenesis, Site-Directed; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D017354:Point Mutation; D012333:RNA, Messenger / Q000378:metabolism; D012367:RNA, Viral / Q000378:metabolism; D015728:Receptors, HIV / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000821:virology*; D014162:Transfection
chemical_list: D015704:CD4 Antigens; D015488:HIV Antigens; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D010446:Peptide Fragments; D012333:RNA, Messenger; D012367:RNA, Viral; D015728:Receptors, HIV