Identification of Human T Cell Targets Recognized during Chlamydia trachomatis Genital Infection

• Published in: The Journal of infectious diseases 2007-11, Vol.196 (10), p.1546-1552
• Main Authors: Olsen, Anja Weinreich, Follmann, Frank, Højrup, Peter, Leah, Robert, Sand, Carsten, Andersen, Peter, Theisen, Michael
• Format: Article
• Language: English
• Subjects: Antigens; Bacteria; Bacteriology; Biological and medical sciences; Case-Control Studies; Chlamydia; Chlamydia Infections - blood; Chlamydia Infections - immunology; Chlamydia Infections - microbiology; Chlamydia trachomatis; Chlamydia trachomatis - genetics; Chlamydia trachomatis - immunology; DNA Primers; DNA, Bacterial - analysis; Epitopes; Fundamental and applied biological sciences. Psychology; Genitalia; Humans; Infections; Membrane proteins; Microbiology; Miscellaneous; Nucleotides; Polymerase Chain Reaction; Recombinant proteins; T lymphocytes; T-Lymphocytes - physiology
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1086/522524

The specificity of the human T cell response to Chlamydia trachomatis was investigated by stimulating lymphocytes from 16 case patients with urogenital infection by use of a size-fractionated serovar D lysate. Considerable heterogeneity was found among case patients, and multiple protein fractions were recognized in each specimen. Mass spectrometry analysis of the 30–42-kDa T cell—stimulating region identified 10 C. trachomatis proteins. Of these, CT583, CT603, and CT610 were identified as strong antigens that induced significantly higher levels of IFN-γ secretion in PBMCs from case patients, compared with PBMCs from control donors. All 3 proteins were recognized in specimens from case patients infected with serovars D–F, the most prevalent serovars. McDonald-Kreitman and Tajima's D tests involving clinical isolates from the same samples showed evidence for frequency-dependent selection on ct583. We predict that CT583 is a target of acquired protective immune responses in humans.