Poster session

[P3-3-26] Development of periodontitis by the systemic immune network via oral-gut axis

〇Jun-ichi Nagao^1,2, Masanobu Nakagami¹, Sari Kishikawa^1,2, Kenji Toyonaga^1,2, Emi Kaji¹, Aoba Iwanuma¹, Kanae Negoro(Yasumatsu)^1,2, Sonoko Tasaki¹, Yoshihiko Tanaka^1,2 (1. Div Infect Biol, Fukuoka Dent Coll, 2. Oral Med Res Ctr, Fukuoka Dent Coll)

Keywords:微生物、獲得免疫、細菌

Periodontitis is an inflammatory disease caused by periodontal bacteria in dental plaque and is the most significant cause of tooth loss. Periodontal disease has been reported to be associated with systemic diseases such as diabetes and rheumatoid arthritis. Recent analyses have reported that the development of periodontitis is regulated by the host immune response to periodontal bacteria, especially the host immune response by Th17 cells characterized by cytokine IL-17A production. However, the regulatory mechanisms of Th17 cells remain unclear, such as what are the antigens that induce immune responses by Th17 cells, where is the site of immune response induction. This study aims to elucidate the development of periodontitis by focusing on systemic Th17 cell-mediated immune responses to periodontal bacteria. Periodontal bacteria are known to translocate the intestinal tract from the oral cavity. We administered Porphyromonas gingivalis, a periodontal bacterium highly associated with periodontitis, to the intestinal tract, and found that P. gingivalis-responsive Th17 cells respond systemically via the intestinal tract. P. gingivalis-responsive Th17 cells are capable of migrating to and accumulating in the periodontal tissue upon oral infection of P. gingivalis, resulting in exacerbation of periodontitis. Furthermore, we found that development of periodontitis via P. gingivalis-responsive Th17 cells is regulated by the intestinal microbiome. These findings demonstrate that the development of periodontitis is regulated by the immune network via Th17 cells between the intestinal tract and oral cavity.