Fine molecular specificity of linear and assembled antibody binding sites in HIV-1 p24.
A set of seven murine monoclonal antibodies were generated against a chemically synthesized 11-kDa 104-mer peptide covering the C-terminal residues 270-373 of the p24 gag protein (HIV-1BRU strain). All monoclonal antibodies recognized HIV-1IIIB infected MOLT3 cells by fluorescence and gave positive Western blot signals with viral gag peptides (p55 and/or p24). Oligopeptide binding regions were located with competitive enzyme-linked immunosorbent assays. Detailed epitope scanning analyses (the Geysen technique) were performed by serological testing of the monoclonal antibodies against 99 overlapping hexapeptides which corresponded to the entire 104-mer region. The antibodies bound to p24 peptide sequences located within the 275-293 and 351-368 regions. One antibody (LH104-B) which reacted with residues 357-362 bound to p55 alone. In contrast, another antibody (LH104-I), which recognized the residues 358-363, i.e. with five out of six residues in common with antibody LH104-B for its epitope region, reacted exclusively with p24. At least two of the antibodies (LH104-C and -A) which bound to p24 alone, apparently recognized conformational epitopes. They gave positive reactions with the regions 288-293/351-356 and 284-289/351-356, respectively. This work shows that chemical synthesis of large peptides is a viable alternative approach to immunochemical studies of viral proteins.
Haaheim
L R
LR
Department of Microbiology and Immunology, Gade Institute, University of Bergen, Norway.
Maskell
J P
JP
Mascagni
P
P
Coates
A R
AR
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology; D000914:Antibodies, Viral / Q000737:chemistry / Q000276:immunology; D000917:Antibody Formation; D001666:Binding Sites, Antibody; D015153:Blotting, Western; D000939:Epitopes / Q000737:chemistry; D015683:Gene Products, gag / Q000276:immunology*; D016655:HIV Core Protein p24; D015497:HIV-1 / Q000276:immunology; D008969:Molecular Sequence Data; D014758:Viral Core Proteins / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D000939:Epitopes; D015683:Gene Products, gag; D016655:HIV Core Protein p24; D014758:Viral Core Proteins