title: Serum levels of matrix metalloproteinase 3 (stromelysin 1) for monitoring synovitis in rheumatoid arthritis.
abstract: BACKGROUND
  Matrix metalloproteinase 3 (MMP-3) is expressed in synovial tissues and involved in cartilage destruction in rheumatoid arthritis and osteoarthritis.
  
  
  OBJECTIVE
  To study whether measurement of MMP-3 serum concentrations is useful to monitor the activity of rheumatoid synovitis.
  
  
  METHODS
  Levels of MMP-3 in serum and synovial tissue samples obtained from 29 rheumatoid arthritis patients and 20 osteoarthritis patients were measured by the 1-step sandwich enzyme immunoassay system.
  
  
  RESULTS
  Levels of MMP-3 in the serum and synovial samples were significantly higher in rheumatoid arthritis than in osteoarthritis (P < .001), and the levels correlated directly with each other (r = 0.712, P < .001; N = 49). Immunohistochemistry demonstrated almost exclusive localization of MMP-3 to the lining cells in rheumatoid synovium. The immunoreactivity correlated directly with the scores of synovial inflammatory cell infiltration (r = 0.606, P < .001; n = 29) and the MMP-3 levels in the synovial tissues (r = 0.564, P = .001; n = 29) and those in the serum samples (r = 0.529, P = .003; n = 29) in rheumatoid arthritis. Levels of MMP-3 in rheumatoid serum samples dropped to low values at 1 and 2 weeks after total knee arthroplasty, while the levels of C-reactive protein increased at 1 week and the erythrocyte sedimentation rate and counts of white blood cells and platelets were unchanged at 1 and 2 weeks postoperative.
  
  
  CONCLUSIONS
  Our results demonstrate that MMP-3 levels in the serum of rheumatoid arthritis patients correlate with the levels produced by the synovial lining cells and suggest that the activity of rheumatoid synovitis can be monitored by measuring serum levels of MMP-3.
authors.affiliation: Department of Pathology, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: Ari
authors.initials: A
authors.lastname: Kobayashi
authors.forename: Satoko
authors.initials: S
authors.lastname: Naito
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Enomoto
authors.forename: Takayuki
authors.initials: T
authors.lastname: Shiomoi
authors.forename: Tokuhiro
authors.initials: T
authors.lastname: Kimura
authors.forename: Ken'ichi
authors.initials: K
authors.lastname: Obata
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Inoue
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Okada
mesh_terms: D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000150:complications; D019645:Arthroplasty, Replacement, Knee; D005260:Female; D006801:Humans; D007118:Immunoassay; D007150:Immunohistochemistry; D008297:Male; D019278:Matrix Metalloproteinase 3 / Q000097:blood*; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000097:blood; D013585:Synovitis / Q000097:blood* / Q000209:etiology
chemical_list: D019278:Matrix Metalloproteinase 3