Prevotella induces IL-10 production in monocytic cells

Abstract

Objective: Clinical remission after immunotherapy for allergic rhinitis is based on an increase in Interleukin-10 (IL-10) production, a regulatory cytokine. We focused on the effect of the oral microbiome on sublingual immunotherapy and investigated the IL-10 production from human monocytic cell line (THP-1 cell) stimulated by one of the commensal gram-negative Prevotella species. Methods: We measured IL-10 production in THP-1 cells stimulated by P. melaninogenica, one of the major bacteria in the Prevotella genus. Lipopolysaccharides (LPS) from Escherichia coli (E. coli) were used to confirm the validity of the experiments. Polymyxin B sulfate salt (PMB), an antibiotic that interacts with LPS, was added to counteract the effect of LPS and P. melaninogenica. Results: P. melaninogenica induced IL-10 production in THP-1 cells (P < 0.01). The IL-10 production in THP-1 cells stimulated with P. melaninogenica was substantially increased when combined with PMB (P < 0.01), whereas IL-10 induced by E. coli LPS was decre- ased when combined with PMB. Conclusion: The IL-10 production in THP-1 cells was induced by P. melaninogenica and was increased when combined with PMB. Further investigations into the mechanisms of IL-10 production induced by Prevotella are needed.