title: Identification of Chlamydia trachomatis Antigens Recognized by T Cells From Highly Exposed Women Who Limit or Resist Genital Tract Infection.
abstract: BACKGROUND
  Natural infection induces partial immunity to Chlamydia trachomatis Identification of chlamydial antigens that induce interferon γ (IFN-) secretion by T cells from immune women could advance vaccine development.
  
  
  METHODS
  IFN-γ production by CD4+and CD8+peripheral blood T cells from 58 high-risk women was measured after coculture with antigen-presenting cells preincubated with recombinant Escherichia coli expressing a panel of 275 chlamydial antigens. Quantile median regression analysis was used to compare frequencies of IFN-γ responses in women with only cervical infection to those in women with endometrial infection and frequencies in women who remained uninfected for over 1 year to those in women who developed incident infection. Statistical methods were then used to identify proteins associated with protection.
  
  
  RESULTS
  A higher median frequency of CD8+T-cell responses was detected in women with lower genital tract chlamydial infection, compared with those with upper genital tract chlamydial infection (13.8% vs 9.5%; P =04), but the CD4+T-cell response frequencies were not different. Women who remained uninfected displayed a greater frequency of positive CD4+T-cell responses (29% vs 18%; P < .0001), compared with women who had incident infection, while the frequencies of CD8+T-cell responses did not differ. A subset of proteins involved in central metabolism, type III secretion, and protein synthesis were associated with protection.
  
  
  CONCLUSIONS
  Investigations in naturally exposed women reveal protective responses and identify chlamydial vaccine candidate antigens.
authors.affiliation: Department of Pediatrics.
authors.forename: Ali N
authors.initials: AN
authors.lastname: Russell
authors.affiliation: Department of Pediatrics.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Department of Pediatrics.
authors.forename: Catherine M
authors.initials: CM
authors.lastname: O'Connell
authors.affiliation: Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh School of Medicine and Magee-Womens Research Institute, Pennsylvania.
authors.forename: Harold C
authors.initials: HC
authors.lastname: Wiesenfeld
authors.affiliation: Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh School of Medicine and Magee-Womens Research Institute, Pennsylvania.
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Hillier
authors.affiliation: Department of Epidemiology and Biostatistics, Texas A&M Health Science Center, College Station.
authors.forename: Brandie D
authors.initials: BD
authors.lastname: Taylor
authors.affiliation: Genocea Biosciences, Cambridge, Massachusetts.
authors.forename: Michelle D
authors.initials: MD
authors.lastname: Picard
authors.affiliation: Genocea Biosciences, Cambridge, Massachusetts.
authors.forename: Jessica B
authors.initials: JB
authors.lastname: Flechtner
authors.affiliation: Department of Biostatistics, University of North Carolina-Chapel Hill.
authors.forename: Wujuan
authors.initials: W
authors.lastname: Zhong
authors.affiliation: Department of Pediatrics.
authors.forename: Lauren C
authors.initials: LC
authors.lastname: Frazer
authors.affiliation: Department of Pediatrics.
authors.forename: Toni
authors.initials: T
authors.lastname: Darville
mesh_terms: D000293:Adolescent; D000328:Adult; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D002478:Cells, Cultured; D002690:Chlamydia Infections / Q000276:immunology* / Q000517:prevention & control*; D002692:Chlamydia trachomatis / Q000276:immunology*; D018920:Coculture Techniques; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008137:Longitudinal Studies; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D060737:Reproductive Tract Infections / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D011994:Recombinant Proteins; D007371:Interferon-gamma
keywords: Chlamydia trachomatis; antigen; genital; vaccine; women