Determination of neutralizing epitopes in variable domains I and IV of the major outer-membrane protein from Chlamydia trachomatis serovar K

• Published in: Microbiology (Society for General Microbiology) Vol. 140; no. 9; pp. 2481 - 2487
• Main Authors: Villeneuve, Anne, Brossay, Laurent, Paradis, Gilles, Hebert, Jacques
• Format: Journal Article
• Language: English
• Published: England Soc General Microbiol 01.09.1994
• Subjects: Amino Acid Sequence; Antibody Specificity; Antigens, Bacterial - genetics; Bacterial Outer Membrane Proteins - genetics; Bacterial Outer Membrane Proteins - immunology; Chlamydia trachomatis; Chlamydia trachomatis - classification; Chlamydia trachomatis - genetics; Chlamydia trachomatis - immunology; Epitopes - genetics; Genetic Variation; Molecular Sequence Data; Neutralization Tests; Peptide Mapping; Serotyping
• ISSN: 1350-0872; 1465-2080
• DOI: 10.1099/13500872-140-9-2481

Centre de Recherche en Inflammation, Immunologie et Rhumatologie, Centre de Recherche du Centre Hospitalier de l'Université Laval, 2705 boul. Laurier, Ste-Foy, Québec, Canada G1V 4G2 ABSTRACT Chlamydia trachomatis is a leading cause of sexually transmitted diseases and a number of strategies have been developed to produce vaccines to prevent its transmission. The purpose of this study was to map the neutralizing epitopes of C. trachomatis major outer-membrane protein (MOMP) serovar K by using anti-MOMP antibodies and synthetic peptides. Seven anti-MOMP monoclonal antibodies and three polyclonal antisera were produced and characterized. Their fine specificity was defined by direct binding assay on 15 peptides of 10 amino acid residues, overlapping by five residues, corresponding to the four variable domains (VDI-VDIV: residues 64-85, 139-160, 224-237 and 287-319) of MOMP serovar K. Our data confirmed that a neutralizing epitope is found in VDIV, defined by peptides K12 and K13. This epitope is 296 TTLNPTIAG 304 , which has never been reported as a neutralizing epitope of serovar K. Another neutralizing epitope, defined by peptide K2, has been identified in VDI. This epitope is in the same position as 71 VAGLEK 76 , a peptide with neutralizing activity found in serovar A, but they are not identical because antibodies against peptide K2 do not bind to this epitope. No neutralizing epitope was found in the two other variable domains (VDII and III). In summary, two neutralizing sites, one in variable domain I and one in variable domain IV, were identified in serovar K. Author for correspondence: Anne Villeneuve. Fax: +1 418 654 2765. Keywords: Chlamydia trachomatis , neutralizing epitopes, vaccines, outer-membrane protein