A new classification of HLA-DRB1 alleles differentiates predisposing and protective alleles for autoantibody production in rheumatoid arthritis

Arthritis Res Ther. 2007;9(2):R27. doi: 10.1186/ar2131.

Abstract

The HLA-DRB1 gene was reported to be associated with anticitrullinated protein/peptide autoantibody (ACPA) production in rheumatoid arthritis (RA) patients. A new classification of HLA-DRB1 alleles, reshaping the shared epitope (SE) hypothesis, was recently found relevant in terms of RA susceptibility and structural severity. We investigated the relevance of this new classification of HLA-DRB1 SE+ alleles in terms of rheumatoid factor (RF) and ACPA production in a sample of French RA patients. We studied 160 early RA patients included in a prospective longitudinal cohort of French Caucasian patients with recent-onset arthritis. RF, anticyclic citrullinated peptide 2 (anti-CCP2) and antideiminated human fibrinogen autoantibodies (AhFibA) were assessed in all patients at inclusion. The HLA-DRB1 gene was typed by PCR-sequence specific oligonucleotides probes (PCR-SSOP), and SE+ alleles were classified into four groups (S1, S2, S3P, S3D) according to the new classification. The new classification of HLA-DRB1 SE+ alleles distinguishes predisposing and protective alleles for RF, anti-CCP2 or AhFibA production. The presence of S2 or S3P alleles is associated with both RF, anti-CCP2 or AhFibA positivity, whereas the presence of S3D or S1 alleles appears to be protective for RF, anti-CCP2 or AhFibA positivity. The new classification of HLA-DRB1 SE+ alleles is relevant in terms of autoantibody production in early RA patients by differentiating predisposing and protective alleles for RF or ACPA production.

MeSH terms

  • Alleles
  • Antibody Formation / genetics*
  • Arthritis, Rheumatoid / blood
  • Arthritis, Rheumatoid / diagnosis
  • Arthritis, Rheumatoid / genetics*
  • Autoantibodies / blood*
  • Biomarkers / blood
  • Cohort Studies
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • HLA-DR Antigens / classification*
  • HLA-DR Antigens / genetics*
  • HLA-DRB1 Chains
  • Humans
  • Male
  • Middle Aged
  • Polymerase Chain Reaction
  • Polymorphism, Genetic
  • Rheumatoid Factor / blood

Substances

  • Autoantibodies
  • Biomarkers
  • HLA-DR Antigens
  • HLA-DRB1 Chains
  • Rheumatoid Factor