Background and Objectives This study evaluates clinical and biological markers of rheumatoid arthritis (RA) severity including matrix metalloproteinase (MMP-3) and Porphyromonas gingivalis (P. gingivalis) serology during infliximab treatment and highlights predictive factors of response to infliximab.
Materials and Methods Joint damage and severe periodontal disease were assessed in 101 RA patients included in this study. DAS28, anti-citrullinated protein antibodies (ACPA), anti-P. gingivalis antibody, and MMP-3 were monitored before and at 6 months of infliximab therapy. ACPA, anti-P. gingivalis antibody, and MMP-3 were determined by ELISA.
Results At baseline, ACPA titers were associated with anti-P. gingivalis LPS-specific antibodies titers (P < 0.05). Anti-P. gingivalis antibodies were not significantly correlated with clinical, biological, or destruction parameters of RA disease. At 6 months of infliximab therapy, MMP-3 level decreased (from 119 ± 103 ng/ml to 62.44 ± 52 ng/ml; P < 0.0001), whereas P. gingivalis antibody levels remained at the same level. DAS28 and inflammation markers (CRP and ESR) also decreased significantly during infliximab therapy (P < 0.05) as ACPA levels (P < 0.001). Only high MMP-3 level at baseline was associated with infliximab efficacy (P < 0.01).
Conclusions MMP-3 level can be a useful marker of the efficacy of infliximab in RA patients. The treatment did not affect anti- P. gingivalis antibodies.