title: Decrement of serum cartilage oligomeric matrix protein (COMP) in rheumatoid arthritis (RA) patients achieving remission after 6 months of etanercept treatment: comparison with CRP, IgM-RF, MMP-3 and anti-CCP Ab.
abstract: OBJECTIVE
  The aim of this study was to evaluate whether serum COMP can estimate the therapeutic response of RA after 6 months of treatment with etanercept.
  
  
  METHODS
  Forty-five RA patients receiving 25 mg of etanercept twice a week for 6 months were registered in this prospective observational study. Clinical response to the therapy was evaluated by DAS 28. Laboratory variables- COMP, CRP, ESR, IgM-RF, MMP-3, and anti-CCP Ab -were assessed at baseline and after 6 months of treatment. We assessed the correlations between serum COMP and other variables and whether serum COMP is associated with DAS28 remission.
  
  
  RESULTS
  Serum COMP correlated with DAS28-ESR (p < 0.05, r = 0.40) at baseline. At 6 months of etanercept treatment, 10 patients entered remission (DAS28-ESR < 2.6) whereas the other 35 patients did not (DAS28-ESR > 2.6). The decrement of serum COMP at 6 months was significant in the remission group (N = 10) but not in the non-remission group (N = 35). On the other hand, CRP, ESR and MMP-3 decreased at 6 months regardless of remission status. IgM-RF titer as well as anti-CCP Ab titer did not differ at 6 months.
  
  
  CONCLUSIONS
  Serum COMP at baseline reflects clinical disease activity of RA. Serum COMP is a valuable serologic marker to identify the subset of RA patients achieving remission during treatment with etanercept.
authors.affiliation: Unit of Translational Medicine, Department of Immunology and Rheumatology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8501, Japan.
authors.forename: Shin-Ya
authors.initials: SY
authors.lastname: Kawashiri
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kawakami
authors.forename: Yukitaka
authors.initials: Y
authors.lastname: Ueki
authors.forename: Takahiro
authors.initials: T
authors.lastname: Imazato
authors.forename: Naoki
authors.initials: N
authors.lastname: Iwamoto
authors.forename: Keita
authors.initials: K
authors.lastname: Fujikawa
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Aramaki
authors.forename: Mami
authors.initials: M
authors.lastname: Tamai
authors.forename: Hideki
authors.initials: H
authors.lastname: Nakamura
authors.forename: Tomoki
authors.initials: T
authors.lastname: Origuchi
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Ida
authors.forename: Katsumi
authors.initials: K
authors.lastname: Eguchi
mesh_terms: D018501:Antirheumatic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000097:blood*; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000032:analysis; D064236:Cartilage Oligomeric Matrix Protein; D000068800:Etanercept; D016326:Extracellular Matrix Proteins / Q000097:blood*; D005260:Female; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D007074:Immunoglobulin G / Q000008:administration & dosage / Q000627:therapeutic use*; D064235:Matrilin Proteins; D019278:Matrix Metalloproteinase 3 / Q000097:blood; D008875:Middle Aged; D011446:Prospective Studies; D018124:Receptors, Tumor Necrosis Factor / Q000008:administration & dosage / Q000627:therapeutic use*; D012074:Remission Induction
chemical_list: D018501:Antirheumatic Agents; D064236:Cartilage Oligomeric Matrix Protein; D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; D007074:Immunoglobulin G; D064235:Matrilin Proteins; D018124:Receptors, Tumor Necrosis Factor; C577553:TSP5 protein, human; D002097:C-Reactive Protein; D019278:Matrix Metalloproteinase 3; D000068800:Etanercept