Peptide Immunogen Mimicry of a Protein-Specific Structural Epitope on Human Choriogonadotropin

• Published in: Science (American Association for the Advancement of Science) 1990-05, Vol.248 (4956), p.736-739
• Main Authors: Bidart, Jean-Michel, Troalen, Federic, Ghillani, Pascale, Rouas, Nathalie, Razafindratsita, Alain, Bohuon, Claude, Bellet, Dominique
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Amino acids; Animals; Antibodies; Antigen-Antibody Complex; Antigenic determinants, haptens, artificial antigens; Antigens; Antiserum; Biological and medical sciences; Chorionic Gonadotropin - genetics; Chorionic Gonadotropin - immunology; Chorionic Gonadotropin, beta Subunit, Human; Epitopes; Epitopes - analysis; Epitopes - genetics; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Glycoprotein Hormones, alpha Subunit - immunology; Hormones; Humans; Immune Sera; Immunization; Laboratory rabbits; Lysine; Medical research; Molecular immunology; Molecular Sequence Data; Peptide Fragments - immunology; Peptide hormones; Protein Conformation; Proteins; Rabbits - immunology; Rabbits as laboratory animals; Receptors; Sequence Homology, Nucleic Acid; Sheep; Synthetic vaccines; Vaccination; Vaccines
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1692160

It is a challenge to construct synthetic immunogens that elicit antibodies (Abs) both directed to conformational epitopes and specific for a complex protein like human choriogonadotropin (hCG). A monoclonal antibody specific for hCG bound to regions around Lys$^{45}$ of the α subunit (hCGα) and Asp$^{112}$ of the β subunit (hCGβ). A peptide comprising residues 46 to 55 of hCGα and residues 106 to 116 of hCGβ elicited Abs in rabbits that were directed to a discontinuous epitope and were specific for hCG. These Abs inhibited the binding of hCG to its receptor. Thus, a synthetic immunogen can mimic a conformational-specific epitope and can be useful for vaccine development.