title: Multiple T cell expansions are found in the blood and synovial fluid of patients with reactive arthritis.
abstract: OBJECTIVE
  To look for evidence of T lymphocyte expansions in the blood and synovial fluid (SF) of patients with reactive arthritis (ReA).
  
  
  METHODS
  Paired peripheral blood and synovial samples from 10 patients with ReA were studied by dual color flow cytometry using T cell receptor (TCR) V beta specific and CD4 or CD8 specific antibodies. Two synovial CD8 expansions were studied by 3 color flow cytometry. Peripheral blood samples from 13 healthy, age matched individuals were studied as controls.
  
  
  RESULTS
  Statistically significant expansions were observed in all patients, occurring in blood and SF CD4 and CD8 compartments, but were most common in the synovial CD8 compartment. Expansions studied in further detail displayed an activated "memory" phenotype. A synovial BV22S1/CD8 expansion was seen in 5/6 patients with sexually acquired ReA.
  
  
  CONCLUSIONS
  Multiple T lymphocyte expansions are found in both the blood and SF of patients with ReA. Expansions were most commonly found in the synovial CD8 compartment, where they appeared to express both activation and memory markers. This indicates that T lymphocytes (and in particular cytotoxic T cells) may play a pathogenic role in ReA. These findings are consistent with either an antigen or a superantigen driven response.
authors.affiliation: Molecular Immunology Group. Oxford University, UK.
authors.forename: R L
authors.initials: RL
authors.lastname: Allen
authors.forename: G M
authors.initials: GM
authors.lastname: Gillespie
authors.forename: F
authors.initials: F
authors.lastname: Hall
authors.forename: S
authors.initials: S
authors.lastname: Edmonds
authors.forename: M A
authors.initials: MA
authors.lastname: Hall
authors.forename: B P
authors.initials: BP
authors.lastname: Wordsworth
authors.forename: A J
authors.initials: AJ
authors.lastname: McMichael
authors.forename: P
authors.initials: P
authors.lastname: Bowness
mesh_terms: D000293:Adolescent; D000328:Adult; D001170:Arthritis, Infectious / Q000097:blood / Q000276:immunology* / Q000473:pathology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007135:Immunoglobulin Variable Region / Q000235:genetics / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D008875:Middle Aged; D000091402:Prohibitins; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics / Q000276:immunology; D013582:Synovial Fluid / Q000166:cytology* / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D007135:Immunoglobulin Variable Region; C000717331:PHB2 protein, human; D000091402:Prohibitins; D016693:Receptors, Antigen, T-Cell, alpha-beta