title: Impact of treatment with infliximab on anticyclic citrullinated peptide antibody and rheumatoid factor in patients with rheumatoid arthritis.
abstract: OBJECTIVE
  To investigate the impact of infliximab treatment on anticyclic citrullinated peptide (anti-CCP) antibody and rheumatoid factor (RF) levels in patients with rheumatoid arthritis (RA).
  
  
  METHODS
  Sera from 33 RA patients receiving infliximab and disease modifying antirheumatic drugs were tested for anti-CCP antibody, IgA-, IgG- and IgM-RF using a commercially available semiquantitative ELISA at baseline, 30 and 54 weeks after treatment.
  
  
  RESULTS
  The serum levels of anti-CCP antibody and IgA-RF decreased significantly after 30 weeks (P = 0.002 and 0.024); however, the decrease was not significant at week 54 (P = 0.147 and 0.207). The decrease in IgG-RF level was not significant at 30 and 54 weeks (P = 0.059 and 0.097). IgM-RF levels, however decreased significantly at 30 and 54 weeks (P = 0.002 and 0.004). A strong correlation between anti-CCP and IgA-, IgG- and IgM-RF was observed at baseline (r(s) = 0.48, 0.43, 0.65, P = < 0.05) and after infliximab treatment at 30 (r(s) = 0.45, 0.46, 0.62, P = < 0.05) and 54 (r(s) = 0.49, 0.45, 0.60, P = < 0.05) weeks.
  
  
  CONCLUSIONS
  Treatment with infliximab results in decreased anti-CCP antibody and IgA-RF early in the course of therapy that is not sustained. IgM-RF declines and remains decreased for at least 54 weeks. Investigations in larger cohorts of RA patients (especially early RA) with longer follow-up are needed to assess the impact of specific therapeutic interventions on anti-CCP antibody and RF levels and the relationship of their levels to disease activity.
authors.affiliation: Center of Excellence for Arthritis and Rheumatology, LSU-HSC-S, 1501 Kings Highway, Shreveport, LA 71130, USA. mahmed3@lsuhsc.edu
authors.forename: M Mubashir
authors.initials: MM
authors.lastname: Ahmed
authors.forename: Eisha
authors.initials: E
authors.lastname: Mubashir
authors.forename: Robert E
authors.initials: RE
authors.lastname: Wolf
authors.forename: Samina
authors.initials: S
authors.lastname: Hayat
authors.forename: Vicky
authors.initials: V
authors.lastname: Hall
authors.forename: Runhua
authors.initials: R
authors.lastname: Shi
authors.forename: Seth Mark
authors.initials: SM
authors.lastname: Berney
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy* / Q000276:immunology; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D000069285:Infliximab; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000097:blood* / Q000276:immunology; D012217:Rheumatoid Factor / Q000097:blood*
chemical_list: D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D007070:Immunoglobulin A; D007075:Immunoglobulin M; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide; D012217:Rheumatoid Factor; D000069285:Infliximab