Reactivities of HIV-1 gag-derived peptides with antibodies of HIV-1-infected and uninfected humans.
A group of 41 peptides, each 24 amino acids long and overlapping with each other by 12 residues spanning the total gag open reading frame (orf) of HIV-1 (HTLV-IIIBH 10 isolate) were synthesized using Fmoc chemistry. The purified compounds were used in ELISA assays and tested for antibody reactivities in sera of human HIV-1-infected and noninfected individuals. Sera of HIV- humans showed reactivity against four defined regions, two in p17, one in p24, and one in p15. The values of these reactivities were elevated especially in serum samples of HIV- individuals showing cross-reaction with gag proteins on Western blot. Amino acid sequence comparison of HIV-1 gag proteins with those of human endogenous retroviruses (ERV K10, ERV 3) revealed significant similarities predominantly in the domains showing elevated antibody cross-reactions. The majority of sera from HIV-1+ individuals showed strong reactivities to the cross-reactive regions and to various other peptide sequences, a sequential epitope recognized by all HIV-1+ sera could, however, not be identified. The results suggest that human individuals may have immune reactions to endogenous retroviral protein sequences, which are enhanced by infections with HIV-1. Specific antibodies to HIV-1 gag proteins are probably mainly directed to tertiary structure defined epitopes formed by particle formation of the p24 monomers to the nucleocapsid.
Haist
S
S
Medizinische Mikorbiologie und Hygiene, Universität Regensburg, Germany.
März
J
J
Wolf
H
H
Modrow
S
S
D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology*; D000595:Amino Acid Sequence; D000918:Antibody Specificity; D003429:Cross Reactions; D015683:Gene Products, gag / Q000276:immunology*; D015483:HIV Antibodies / Q000097:blood / Q000276:immunology*; D016655:HIV Core Protein p24 / Q000276:immunology; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000276:immunology*; D017386:Sequence Homology, Amino Acid
D015683:Gene Products, gag; D015483:HIV Antibodies; D016655:HIV Core Protein p24; D010446:Peptide Fragments