title: Peptides as antigens. Importance of orientation.
abstract: Factors known to be important in producing protein-reactive peptide antibodies include the accessibility of the region from which the peptide sequence is derived, the hydrophilic-phobic character of the sequence, and the length of the peptide. The data presented here indicate that the orientation of the peptide coupled to a carrier protein also influences the binding pattern of peptide antibodies. An octapeptide, representing a sequence from the alpha chain of the human acetylcholine receptor, was coupled either through an N- or C-terminal cysteine-glycine-glycine linker to a carrier protein and used to immunize rabbits. The resulting antisera reacted at comparable titers to the uncoupled immunizing peptides, but did not crossreact with the identical but opposite-linked peptide. Characterization of the binding to other homologous peptides showed that immunization with the N-terminal-linked peptide induced antibodies reactive specifically with the C-terminal amino acid(s). Immunization with the C-linked peptide resulted in antibodies reactive with a site of the peptide near the C-terminus.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000941:Antigens / Q000276:immunology*; D007114:Immunization; D010455:Peptides / Q000276:immunology*; D011817:Rabbits; D011950:Receptors, Cholinergic / Q000276:immunology; D013329:Structure-Activity Relationship
chemical_list: D000941:Antigens; D010455:Peptides; D011950:Receptors, Cholinergic