title: In vivo genetic variability of the human immunodeficiency virus type 2 V3 region.
abstract: The principal neutralizing epitope of the human immunodeficiency virus type 1 (HIV-1) lies between two invariant cysteines in the third variable region (V3) of the viral envelope (gp120), and its amino acid sequence varies among different HIV-1 isolates. HIV-2 carries an analogous amino acid sequence between two cysteines of the V3 regions, but its functional similarity with the HIV-1 principal neutralizing epitope is uncertain. We studied the degree of genetic variation of the HIV-2 V3 region in fresh blood samples from 12 HIV-2-seropositive individuals from Guinea-Bissau. Polymerase chain reaction was used to amplify viral fragments of 465 bp containing the V3 region from cellular DNA. Nucleotide sequence analysis of the entire envelope fragment from each patient revealed that the degree of variation among field isolates of HIV-2 is comparable to that observed in the analogous region of HIV-1. Most of the HIV-2 isolates studied were highly related, suggesting the existence of a limited number of different viral strains in the cohort studied. Thus, the HIV-2 and HIV-1 V3 regions vary to a similar degree and may also have analogous functions.
authors.affiliation: Laboratory of Tumor Cell Biology, National Cancer Institute, Bethesda, Maryland 20892.
authors.forename: E
authors.initials: E
authors.lastname: Boeri
authors.forename: A
authors.initials: A
authors.lastname: Giri
authors.forename: F
authors.initials: F
authors.lastname: Lillo
authors.forename: G
authors.initials: G
authors.lastname: Ferrari
authors.forename: O E
authors.initials: OE
authors.lastname: Varnier
authors.forename: A
authors.initials: A
authors.lastname: Ferro
authors.forename: S
authors.initials: S
authors.lastname: Sabbatani
authors.forename: W C
authors.initials: WC
authors.lastname: Saxinger
authors.forename: G
authors.initials: G
authors.lastname: Franchini
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D004279:DNA, Viral; D015686:Gene Products, env / Q000235:genetics*; D014644:Genetic Variation; D015699:HIV Envelope Protein gp120 / Q000235:genetics; D006679:HIV Seropositivity / Q000382:microbiology; D015497:HIV-1 / Q000235:genetics; D015498:HIV-2 / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000235:genetics; D016133:Polymerase Chain Reaction; D011498:Protein Precursors / Q000235:genetics*; D016415:Sequence Alignment; D015302:Simian Immunodeficiency Virus / Q000235:genetics; D014759:Viral Envelope Proteins; D054299:env Gene Products, Human Immunodeficiency Virus
chemical_list: D004279:DNA, Viral; D015686:Gene Products, env; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D010446:Peptide Fragments; D011498:Protein Precursors; D014759:Viral Envelope Proteins; D054299:env Gene Products, Human Immunodeficiency Virus; C066316:gp125 envelope protein, Human immunodeficiency virus 2