No Obvious Role for Suspicious Oral Pathogens in Arthritis Development

Area of Science:

• Oral microbiology
• Immunology
• Rheumatology

Background:

• Porphyromonas gingivalis (Pg) and Aggregatibacter actinomycetemcomitans (Aa) have been implicated in periodontitis and rheumatoid arthritis (RA).
• These bacteria are hypothesized to trigger the production of rheumatoid factor (RF) and anticitrullinated protein autoantibodies (ACPA).

Purpose of the Study:

• To determine if serum antibodies against Pg and Aa correlate with the subgingival presence of these bacteria in RA patients and controls.
• To investigate the association between these antibodies and periodontal inflammation severity, as well as RA-specific autoantibodies (ACPA and RF).

Main Methods:

• Bacterial 16S rRNA gene sequencing was used to assess subgingival Pg and Aa presence in 70 Indonesian RA patients and 70 non-RA controls.
• Serum IgG levels specific for Pg and Aa were measured.
• Serum ACPA (IgG, IgA) and RF (IgM, IgA) levels were quantified, and periodontal inflammation was assessed using the periodontal inflamed surface area.

Main Results:

• Subgingival presence of Pg and Aa was similar in both RA patients and controls.
• Serum anti-Pg and anti-Aa antibody levels correlated with the subgingival presence of the respective bacteria.
• No significant correlation was found between anti-Pg antibodies and ACPA or RF levels, nor between subgingival Pg/Aa and RA.

Conclusions:

• Serum antibody levels against Pg and Aa accurately reflect their subgingival presence.
• The subgingival presence of Pg and Aa, and the corresponding serum antibodies, are not associated with rheumatoid arthritis or its specific autoantibodies.