The regulation of oral microbiota by IgA

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K10068
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 57020:Oral pathobiological science-related
• Research Institution: Hyogo Medical University (2021-2022); The University of Tokyo (2019)
• Principal Investigator: Son Aoi 兵庫医科大学, 医学部, 講師 (30447924)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 口腔内細菌叢 / 腸内細菌叢 / 免疫細胞

Outline of Final Research Achievements

The original research plan was to screen for oral bacteria to which mouse intestine-derived monoclonal IgA antibodies bind, but the applicant's research institution changed during the first year and the mouse intestine-derived monoclonal IgA library could no longer be used, so the research plan was revised. Based on a report that oral bacteria were identified in stool samples from patients with inflammatory bowel disease, we conducted research on the relationship between oral bacteria and the development of inflammatory bowel disease. First, we searched for oral bacteria in the intestinal tract by next-generation sequencing analysis. As a result, the presence of oral bacteria such as Fusobacterium and Bifidobacterium was confirmed. Furthermore, when these bacteria were isolated and orally administered to antibiotic-treated mice, an increase in CD11b-positive cells in the coloc was observed in mice treated with Fusobacterium.

Free Research Field

細菌叢解析　免疫学

Academic Significance and Societal Importance of the Research Achievements

近年、炎症性腸疾患は生産年齢層を中心に患者数が増加しており、社会的問題となっている。その発症には腸内細菌の乱れ（dysbiosis）が原因の一つであると言われているが、宿主側の恒常性維持力や免疫応答バランスも関与していると考えられ、その因果関係を明らかにすることは容易ではない。炎症性腸疾患患者の便サンプルから口腔内細菌が確認されたことから、口腔内細菌叢と腸内細菌叢の関連性について注目が高まっている。潰瘍性大腸炎に代表される炎症性腸疾患は、根本的な治療法や病因が確立されておらず口腔内細菌叢と関連からアプローチする。