title: Immunizations of monkeys with synthetic peptides disclose conserved areas on gp120 of human immunodeficiency virus type 1 associated with cross-neutralizing antibodies and T-cell recognition.
abstract: Site-directed immunization was employed to identify sites on the envelope glycoprotein gp120 for antibody-mediated neutralization of human immunodeficiency virus type 1 (HIV-1). Antisera were raised in monkeys (Macaca fascicularis) against a series of 40 overlapping synthetic peptides covering the entire amino acid sequence of gp120 from the HTLV-IIIB strain of HIV-1. Immune sera against 12 of these peptides were reactive with gp120 by immunoblotting analysis, and antisera raised against 5 peptides, corresponding to amino acids (aa) 152-176, 193-218, 206-230, 248-269, and 307-330, were highly efficient in neutralizing HIV-1 (HTLV-IIIB) infectivity in vitro. Admixture of individual neutralizing anti-peptide monkey sera resulted in increment in neutralizing antibody titer. Antisera with reactivity to the relatively conserved regions defined by aa 152-176, 193-230, and 248-269 also neutralized to different extents the infectivity of the five Swedish clinical isolates of HIV-1 tested. Only a few HIV-1-infected people were found to make antibodies to these three conserved domains of gp120 as judged by ELISA using synthetic peptides as antigens. Three of the peptides (aa 152-176, 248-269, and 307-330) that induced neutralization antibodies also induced interleukin 2 production and lymphocyte proliferation when added to cultures of peripheral blood mononuclear cells from monkeys immunized with the corresponding peptides, indicating that these domains accommodate T-cell recognition sites. The results have obvious implications for the rational design of subunit vaccines against HIV-1 infection.
authors.affiliation: Department of Clinical Virology, University of Göteborg, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Vahlne
authors.forename: P
authors.initials: P
authors.lastname: Horal
authors.forename: K
authors.initials: K
authors.lastname: Eriksson
authors.forename: S
authors.initials: S
authors.lastname: Jeansson
authors.forename: L
authors.initials: L
authors.lastname: Rymo
authors.forename: K G
authors.initials: KG
authors.lastname: Hedström
authors.forename: C
authors.initials: C
authors.lastname: Czerkinsky
authors.forename: J
authors.initials: J
authors.lastname: Holmgren
authors.forename: B
authors.initials: B
authors.lastname: Svennerholm
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology*; D000595:Amino Acid Sequence; D000818:Animals; D000917:Antibody Formation; D002460:Cell Line; D002478:Cells, Cultured; D004261:DNA Replication; D015699:HIV Envelope Protein gp120 / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007114:Immunization; D015151:Immunoblotting; D007074:Immunoglobulin G / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008252:Macaca fascicularis / Q000276:immunology*; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D010455:Peptides / Q000138:chemical synthesis / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D015699:HIV Envelope Protein gp120; D007074:Immunoglobulin G; D010455:Peptides