title: Telomerase activity in rheumatoid synovium correlates with the mononuclear cell infiltration level and disease aggressiveness of rheumatoid arthritis.
abstract: OBJECTIVE
  To determine whether the presence of telomerase activity in synovial tissues could provide insights into the pathogenesis of rheumatoid arthritis (RA).
  
  
  METHODS
  Synovial tissue samples obtained from patients with RA or osteoarthritis (OA) were examined for telomerase activity using the telomeric repeat amplification protocol (TRAP).
  
  
  RESULTS
  Telomerase activity was detected in over half the RA synovial tissues (14/25, 56%) but in no OA synovial tissue samples (0/15). Telomerase activity was detected in the mononuclear cells isolated from telomerase-positive RA synovial tissue, but not in cultured adherent cells. In RA synovial tissue with positive telomerase activity mononuclear cell infiltration levels were increased (p < 0.001). In addition, patients with RA with positive telomerase activity had undergone joint operations at an earlier age (p = 0.030) and more often (p = 0.023) compared to those without telomerase activity.
  
  
  CONCLUSIONS
  Telomerase activity in RA synovial tissue is likely derived from infiltrating mononuclear cells and may be involved in the pathogenesis of RA. Clinically, the presence of telomerase activity in RA may be an indicator of a more aggressive phenotype.
authors.affiliation: Second Department of Internal Medicine, Hiroshima University School of Medicine, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Yamanishi
authors.forename: K
authors.initials: K
authors.lastname: Hiyama
authors.forename: H
authors.initials: H
authors.lastname: Maeda
authors.forename: S
authors.initials: S
authors.lastname: Ishioka
authors.forename: T
authors.initials: T
authors.lastname: Murakami
authors.forename: E
authors.initials: E
authors.lastname: Hiyama
authors.forename: Y
authors.initials: Y
authors.lastname: Kurose
authors.forename: J W
authors.initials: JW
authors.lastname: Shay
authors.forename: M
authors.initials: M
authors.lastname: Yamakido
mesh_terms: D000368:Aged; D001172:Arthritis, Rheumatoid / Q000201:enzymology* / Q000473:pathology; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007963:Leukocytes, Mononuclear / Q000166:cytology* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010003:Osteoarthritis / Q000201:enzymology / Q000473:pathology; D013583:Synovial Membrane / Q000201:enzymology*; D019098:Telomerase / Q000378:metabolism*
chemical_list: D019098:Telomerase