The commensal gut organism, Prevotella copri (Pc), has been reported to play an immunological role in patients with rheumatoid arthritis. As such, researchers investigated anti-Pc antibody responses and when they developed during the natural disease history in a cohort of patients with rheumatoid arthritis. According to the study’s lead author, Jennifer Seifert, MPH, the study’s results suggest that Pc does appear to play a role in rheumatoid arthritis evolution.
This study assessed serum levels of immunoglobulin A (IgA) and immunoglobulin G (IgG) anti-Pc-p27, an immunogenic Pc protein, in patients who were: at-risk for development of rheumatoid arthritis, transitioned to rheumatoid arthritis, in the first year of rheumatoid arthritis, and in established rheumatoid arthritis. Anti-Pc-p27 antibodies were also evaluated in subgroups stratified according to rheumatoid arthritis-related autoantibody status. Measurements were compared against matched controls.
Prevotella Copri Appears to Drive Rheumatoid Arthritis and Synovitis
The researchers reported that patients with rheumatoid arthritis had significantly higher levels of IgA anti-Pc-p27, and trended towards higher levels of IgG anti-Pc-p27, when compared with matched controls. Patients in early rheumatoid arthritis had overall higher median IgG anti-Pc-p27 antibodies compared with established disease, while patients with established disease had significantly higher median IgA anti-Pc-p27 compared with their matched controls.
Additionally, in autoantibody analyses, the investigators found that the at-risk subjects with anti-CCP but without anti-RF antibodies trended towards increased levels of IgG anti-Pc-p27. Similarly, patients with both anti-CCP and -RF antibodies had significantly increased IgA anti-Pc-p27 antibodies and trended towards increased IgG anti-Pc-p27 antibodies when compared with matched controls.
In summary, “these findings support a potential etiologic role for this microorganism in both RA preclinical evolution and the subsequent pathogenesis of synovitis,” the authors closed.