Elucidation of the mechanisms of host physiological homeostasis by intestinal mucosa-associated microbiota

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K16251
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 49050:Bacteriology-related
• Research Institution: Keio University
• Principal Investigator: YANG Jiayue 慶應義塾大学, 政策・メディア研究科(藤沢), 特任助教 (10804825)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 腸内細菌 / 腸管粘膜 / 腸管粘膜細菌 / 炎症性腸疾患 / 大腸炎

Outline of Final Research Achievements

Various commensal bacteria inhabit our human intestine. Particularly, the intestinal mucosal bacteria have been reported to impact host health by modulation of the host immune system. Therefore, it is important to identify the mucosal bacteria and elucidate their function further. However, the knowledge of mucosa-associated bacteria is limited due to the conventional invasive sampling method. In this study, we discovered that a bacterial taxon is a novel mucosa-associated bacterium and inhabits not only the colon mucosal layer but also in the crypt of small intestine. This bacterium alone could not colonize in germ-free mice and required co-colonization. Dextran sodium sulfate (DSS) colitis model is a mice experimental model for human Inflammatory bowel diseases. Gnotobiotic mice with this bacterium greatly improved the survival rate and the symptom of DSS-induced colitis. Thus, this bacterium could influence the host health by the modulation of intestinal immune system.

Free Research Field

腸内細菌

Academic Significance and Societal Importance of the Research Achievements

IBDは腸管免疫の破綻によって引き起こされる病気であり、腸内細菌叢が深く関与しており、患者数は増加の一途を辿っている。しかしながら、疾患の要因が多種多様であり完全に解明されておらず、根本的な治療法が確立していないため、根治は難しく、患者は社会的活動を中断せざるを得ないケースが多く存在する。そのため、有効な治療法の開発が求められる。本研究で発見した新規の腸管粘膜近傍局在細菌はIBDの治療法の開発に応用可能だと考えられる。