title: Serotyping HIV type 1 by antibody binding to the V3 loop: relationship to viral genotype. WHO Network for HIV Isolation and Characterization.
abstract: We have investigated whether peptides representing the HIV-1 principal neutralization domain (V3) can be used as antigens in antibody-binding assays to predict the genotypes of the subjects' virus. Serum samples collected from HIV-1-infected subjects from the four WHO-sponsored vaccine evaluation sites (Uganda, Rwanda, Thailand, and Brazil) were characterized by antibody binding to a panel of synthetic V3 peptides that were derived from the consensus sequences of the V3 region of the HIV-1 subgroups according to the env phylogenetic analysis (A-E). An indirect V3 peptide-binding assay was used for primary screening, and a V3 peptide antigen-limiting ELISA was then used as a secondary assay to discriminate cross-reactivity if the screening assay was equivocal. In general, V3 peptide serology could predict HIV-1 genotypes. In sera for which the genotype of the virus was known, peptide assays could predict the correct genotype in approximately 90% of cases for genotypes A, B, C, and E; Ugandan sera of genotype D were more broadly reactive. There was considerable serological cross-reactivity between some HIV-1 genotypes, in particular between A and C, and, to a lesser extent, B and D subtypes. Owing to polymorphism at the crown of the V3 loop, an additional B peptide (B') was required to type Brazilian B genotype sera. These simple assays may help facilitate the determination and distribution of HIV-1 genotypes circulating in populations.
authors.affiliation: Department of Genito-Urinary Medicine and Communicable Diseases, St. Mary's Hospital Medical School, London, U.K.
authors.forename: R
authors.initials: R
authors.lastname: Cheingsong-Popov
authors.forename: S
authors.initials: S
authors.lastname: Lister
authors.forename: D
authors.initials: D
authors.lastname: Callow
authors.forename: P
authors.initials: P
authors.lastname: Kaleebu
authors.forename: S
authors.initials: S
authors.lastname: Beddows
authors.forename: J
authors.initials: J
authors.lastname: Weber
mesh_terms: D016915:AIDS Vaccines / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D000940:Antigenic Variation; D001938:Brazil / Q000453:epidemiology; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005838:Genotype; D015483:HIV Antibodies; D015488:HIV Antigens / Q000235:genetics; D015699:HIV Envelope Protein gp120 / Q000235:genetics / Q000276:immunology*; D015658:HIV Infections / Q000453:epidemiology / Q000821:virology; D015497:HIV-1 / Q000145:classification* / Q000235:genetics / Q000276:immunology; D006801:Humans; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000235:genetics / Q000276:immunology*; D011817:Rabbits; D012432:Rwanda / Q000453:epidemiology; D012703:Serotyping / Q000379:methods*; D013785:Thailand / Q000453:epidemiology; D014454:Uganda / Q000453:epidemiology; D014944:World Health Organization
chemical_list: D016915:AIDS Vaccines; D015483:HIV Antibodies; D015488:HIV Antigens; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D010446:Peptide Fragments