Elucidation of colon homeostasis focusing on the crosstalk between gut microbiota and IL-5-producing cells

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K05499
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 38050:Food sciences-related
• Research Institution: Toyama Prefectural Institute for Pharmaceutical Research
• Principal Investigator: Yanagibashi Tsutomu 富山県薬事総合研究開発センター, その他部局等, 主任研究員 (60710887)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: IgA / IL-5 / 腸内細菌

Outline of Final Research Achievements

There are more than 1000 species of symbiotic microbiota in the human intestine. Recent studies have shown that gut dysbiosis is associated with the pathogenesis of several diseases. Host immunity is thought to regulate the composition of microorganisms, but the details are largely unknown. This study focused on the relationship between interleukin-5 (IL-5), which is constantly produced by group 2 innate lymphoid cells in the large intestine, and the symbiotic microbial flora. In this study, we demonstrated that a part of the T cell-independent immunoglobulin A, one of the regulators of symbiotic homeostasis, is produced in an IL-5-dependent manner. In addition, intestinal dysbiosis was observed in T cell and IL-5 double knockout mice. These results indicate that IL-5 contributes appropriate composition of the gut microbiota via T cell-independent IgA production.

Free Research Field

食品科学

Academic Significance and Societal Importance of the Research Achievements

本研究では，大腸で恒常的に産生されているインターロイキン（IL）-5が，免疫グロブリンA産生を介して腸内細菌の構成バランスの維持に寄与することを示し，宿主免疫系による腸内細菌制御機構の一端を明らかにした。近年，腸内細菌の構成バランスの破綻が，炎症腸疾患，代謝疾患および神経疾患等の原因となることが明らかにされつつあり，これら疾病の治療や予防に腸内細菌を適正な状態に維持する取り組みがなされている。本研究の成果から，腸管IL-5産生量を適正に調節することで，腸内細菌構成バランスの破綻に起因する疾病の予防や治療へ応用が可能であると考える。