title: The neutralization relationship of HIV type 1, HIV type 2, and SIVcpz is reflected in the genetic diversity that distinguishes them.
abstract: Neutralizing antibody (NA) patterns in the sera of individuals naturally infected with human immunodeficiency virus (HIV) type 1, HIV-2, and the simian immunodeficiency virus (SIVcpz) to their homologous and heterologous isolates were determined in a peripheral blood mononuclear cell-based neutralization assay. We examined the role of the V3 loop of HIV-1 and SIVcpz in neutralization and the cross-reactivities among them. Cross-neutralization by sera of humans and chimpanzees naturally infected, respectively, with HIV-1 and SIVcpz isolates was more extensive than the infrequent and low-titer cross-neutralizations observed between HIV-1 and HIV-2. Neutralization of 9 of the 16 HIV-1 isolates by 9 of 10 HIV-2 and all 3 SIVcpz antibody-positive sera were weak and sporadic (titer, 1:10-1:160). Twelve of 15 HIV-1 sera neutralized the 2 SIVcpz isolates with titers of 1:10-1:320 but only sporadically neutralized the 6 HIV-2 isolates (titers: 1:10-1:20). The majority of HIV-1 and SIVcpz sera bound to the V3 peptides although their binding capacity did not readily reflect their neutralizing capacity. The HIV-2 sera did not or only weakly bound to the V3 peptides. These results suggest that HIV-1 and SIVcpz share some structural and functional similarities that set them apart from HIV-2.
authors.affiliation: Department of Microbiology, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: P N
authors.initials: PN
authors.lastname: Nyambi
authors.forename: B
authors.initials: B
authors.lastname: Willems
authors.forename: W
authors.initials: W
authors.lastname: Janssens
authors.forename: K
authors.initials: K
authors.lastname: Fransen
authors.forename: J
authors.initials: J
authors.lastname: Nkengasong
authors.forename: M
authors.initials: M
authors.lastname: Peeters
authors.forename: K
authors.initials: K
authors.lastname: Vereecken
authors.forename: L
authors.initials: L
authors.lastname: Heyndrickx
authors.forename: P
authors.initials: P
authors.lastname: Piot
authors.forename: G
authors.initials: G
authors.lastname: van der Groen
mesh_terms: D000818:Animals; D003429:Cross Reactions; D014644:Genetic Variation / Q000276:immunology*; D015483:HIV Antibodies / Q000097:blood*; D015699:HIV Envelope Protein gp120 / Q000378:metabolism; D015497:HIV-1 / Q000145:classification / Q000235:genetics / Q000276:immunology*; D015498:HIV-2 / Q000145:classification / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007106:Immune Sera; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D002679:Pan troglodytes; D010446:Peptide Fragments / Q000378:metabolism; D010802:Phylogeny; D012703:Serotyping; D015302:Simian Immunodeficiency Virus / Q000145:classification / Q000235:genetics / Q000276:immunology*
chemical_list: D015483:HIV Antibodies; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D007106:Immune Sera; D010446:Peptide Fragments