title: The specific antibacterial proliferation of reactive arthritis synovial T cells is not due to their higher proportion of CD45RO+ cells compared to peripheral blood.
abstract: OBJECTIVE
  To determine the role of synovial fluid (SF) compared to peripheral blood (PB) CD45RO+ T cells in patients with reactive arthritis (ReA) and undifferentiated oligoarthritis.
  
  
  METHODS
  We examined SF and PB of 8 patients with a specific lymphocyte proliferation to Yersinia enterocolitica (n = 5) and Chlamydia trachomatis (n = 3). After depletion of the CD45RA+ T cell subset by dynabeads, the remaining T cells (> 95% CD45RO+) from PB and SF of these patients were again stimulated with these bacterial antigens.
  
  
  RESULTS
  The mean stimulation index (SI) of these 8 patients with ReA (n = 5) and undifferentiated oligoarthritis (n = 3) was 30.3 +/- 21.86 in SF compared to 1.36 +/- 0.75 in PB. The enrichment of CD45RO+ cells influenced the antigen specific proliferative response of T cells neither in PB (SI = 1.75 +/- 1.35) nor in SF (26.1 +/- 24.05); the initial difference remained unchanged.
  
  
  CONCLUSIONS
  Our findings suggest that the antigen specific lymphocyte proliferation obtained with SF cells is not due to abundance of nonspecific CD45RO+ T cells but can rather be taken as an indication of specific recognition of local bacterial antigens in ReA.
authors.affiliation: Abteilung für Allgemeine Innere Medizin und Nephrologie, Klinikum Steglitz, Freien Universität, Berlin, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Braun
authors.forename: M
authors.initials: M
authors.lastname: Grolms
authors.forename: A
authors.initials: A
authors.lastname: Distler
authors.forename: J
authors.initials: J
authors.lastname: Sieper
mesh_terms: D000328:Adult; D016918:Arthritis, Reactive / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D002692:Chlamydia trachomatis / Q000276:immunology; D005260:Female; D006801:Humans; D017493:Leukocyte Common Antigens / Q000032:analysis*; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D000091402:Prohibitins; D013582:Synovial Fluid / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D015008:Yersinia enterocolitica / Q000276:immunology
chemical_list: C000717331:PHB2 protein, human; D000091402:Prohibitins; D017493:Leukocyte Common Antigens