Periodontitis in RA-the citrullinated enolase connection

Nat Rev Rheumatol. 2010 Dec;6(12):727-30. doi: 10.1038/nrrheum.2010.139. Epub 2010 Sep 7.


Autoimmunity in rheumatoid arthritis (RA) is characterized by an antibody response to citrullinated proteins. Two of the risk factors for RA-HLA-DRB1 shared epitope alleles and smoking-are also associated with periodontitis, which is largely, but not exclusively, caused by Porphyromonas gingivalis infection. Furthermore, RA and periodontitis have a similar pathophysiology, characterized by destructive inflammation. The citrullination of proteins by P. gingivalis and the subsequent generation of autoantigens that drive autoimmunity in RA represents a possible causative link between these two diseases. Antibodies directed towards the immunodominant epitope of human citrullinated α-enolase cross-react with a conserved sequence on citrullinated P. gingivalis enolase. On the basis of this cross-reactivity, in this Perspectives article we explore the hypothesis of molecular mimicry in the etiology of RA, with citrullinated enolase as the specific antigen involved.

Publication types

  • Review

MeSH terms

  • Arthritis, Rheumatoid / etiology*
  • Arthritis, Rheumatoid / immunology
  • Arthritis, Rheumatoid / physiopathology
  • Autoimmunity / physiology
  • Bacteroidaceae Infections / complications
  • Citrulline / metabolism
  • Humans
  • Periodontitis / etiology*
  • Periodontitis / immunology
  • Periodontitis / physiopathology
  • Phosphopyruvate Hydratase / immunology
  • Phosphopyruvate Hydratase / physiology*
  • Porphyromonas gingivalis / physiology
  • Risk Factors


  • Citrulline
  • Phosphopyruvate Hydratase