title: Heterogeneity of anticitrullinated peptide antibodies and response to anti-tumor necrosis factor agents in rheumatoid arthritis.
abstract: OBJECTIVE
  To examine fine specificity of anticitrullinated peptide antibodies (ACPA) in relation to responsiveness to anti-tumor necrosis factor (anti-TNF) agents in rheumatoid arthritis (RA).
  
  
  METHODS
  Samples from 450 patients with RA treated with anti-TNF agents were analyzed for antibodies to citrullinated α-enolase, vimentin, and fibrinogen peptides. The Disease Activity Score-28 was measured at baseline and 6 months.
  
  
  RESULTS
  Both anti-cFib antibodies and the number of citrullinated peptides recognized were associated with a poorer response. These findings were not significant following stratification for anti-cyclic citrullinated peptide 2 antibodies.
  
  
  CONCLUSIONS
  The presence of any ACPA rather than individual ACPA specificities was associated with a poorer response to anti-TNF agents. We suggest that this reflects distinctive differences in the pathogenesis of ACPA-positive and negative RA.
authors.affiliation: Kennedy Institute of Rheumatology, Imperial College London, London, UK. benjamin.fisher@imperial.ac.uk
authors.forename: Benjamin A
authors.initials: BA
authors.lastname: Fisher
authors.forename: Darren
authors.initials: D
authors.lastname: Plant
authors.forename: Karin
authors.initials: K
authors.lastname: Lundberg
authors.forename: Peter
authors.initials: P
authors.lastname: Charles
authors.forename: Anne
authors.initials: A
authors.lastname: Barton
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Venables
mesh_terms: D000368:Aged; D000918:Antibody Specificity / Q000276:immunology; D018501:Antirheumatic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000276:immunology; D004268:DNA-Binding Proteins / Q000276:immunology; D005260:Female; D005340:Fibrinogen / Q000276:immunology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000276:immunology*; D010751:Phosphopyruvate Hydratase / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*; D025521:Tumor Suppressor Proteins / Q000276:immunology; D014746:Vimentin / Q000276:immunology
chemical_list: D018501:Antirheumatic Agents; D001323:Autoantibodies; D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D010456:Peptides, Cyclic; D014409:Tumor Necrosis Factor-alpha; D025521:Tumor Suppressor Proteins; D014746:Vimentin; C487763:cyclic citrullinated peptide; D005340:Fibrinogen; C095157:ENO1 protein, human; D010751:Phosphopyruvate Hydratase