Elucidation of mechanism of E. coli antigen changes and functionality of diversified O-antigens

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K08780
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Bacteriology (including mycology)
• Research Institution: University of Miyazaki
• Principal Investigator: Iguchi Atsushi 宮崎大学, 農学部, 准教授 (00437948)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 大腸菌

Outline of Final Research Achievements

In this study, we aimed to clarify the characteristics of the O-antigen type of E. coli normally present in healthy humans and to clarify the functionality of the O-antigen sugar chain by using such information.OgGp10 (containing O13, O129 and O135), Og1 and Og25 were found to be the major types as a result of O-type full-typing PCR with E. coli strain 312 from healthy humans.Moreover, as a result of measuring the amount of TNF-α production from macrophage-like cells using seven types of O-antigen strains including O1, O25 and O157, it became clear that the inducibility at O157 is remarkably low.

Free Research Field

細菌学

Academic Significance and Societal Importance of the Research Achievements

グラム陰性細菌の表層にはO抗原と呼ばれる糖鎖が発現しており、これまでに180種類以上あることが知られている。本研究では、この糖鎖に何らかの機能性があるのではないかと考え、ヒト常在大腸菌に見られる型と病原性大腸菌に見られる型を用いて、免疫細胞の反応性を試験した。その結果、腸管出血性大腸菌で有名なO157型は、他の型に比べて免疫反応を誘導しにくいことが明らかとなった。この成果は、今後の腸管出血性大腸菌の感染メカニズの解明や治療法の開発に役立つかもしれない。