Periodontal pathogen exposure facilitates disease activity in Systemic Lupus Erythematosus

Abstract

Abstract This study was undertaken to evaluate whether exposure to subgingival plaque bacteria and periodontal dysbiosis influences disease parameters in systemic lupus erythematosus (SLE). Circulating antibodies to periodontal bacteria are surrogate markers to determine an ongoing bacterial burden, or are indicators of past exposure. SLE patient sera in the Oklahoma Lupus Cohort (n=303) were used to measure antibody titers against periodontal pathogens (A. actinomycetemcomitans, P. gingivalis, and T. denticola) and commensals (C. ochracea and S. gordonii) by ELISA. Correlations between anti-bacterial antibodies and clinical parameters of SLE including autoantibodies, complement, and disease activity (SLEDAI and BILAG) were studied. The effect of oral infection with A. actinomycetemcomitans on SLE in NZM2328 lupus mice was evaluated. SLE patients had varying amounts of antibodies to different oral bacteria. The antibody titers against A. actinomycetemcomitans, P. gingivalis, T. denticola, and C. ochracea were higher in patients positive for anti-dsDNA, and in patients with low complement. Only antibodies to A. actinomycetemcomitans and P. gingivalis, but not T. denticola, were associated with higher disease activity. A. actinomycetemcomitans infected NZM2328 mice developed an increase in histone reactive T cells and an accelerated onset of proteinuria, and lupus nephritis. Our results indicate that exposure to only specific pathogenic periodontal bacteria influences disease activity in SLE patients. The results from lupus mice suggest that this may be due to the amplification of local autoimmunity in response to infection. These findings provide a rationale for assessing and improving periodontal health in SLE patients.