Elucidation o the physiological functions of membrane vesicles produced by fermented food-derived bacteria and their application

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K05352
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 38020:Applied microbiology-related
• Research Institution: Kindai University
• Principal Investigator: Kurata Atsushi 近畿大学, 農学部, 教授 (10416000)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 細胞外膜小胞 / 腸内細菌 / 抗体 / 蛍光顕微鏡観察 / 免疫賦活作用 / タンパク質 / サイトカイン / Toll様受容体

Outline of Final Research Achievements

Membrane vesicles (MVs) are spherical bioactive nanoparticles that range in size between 50 and 100 nm and are naturally secreted by many bacteria. MVs released from gut bacteria are becoming increasingly recognized as having a significant impact on host biological functions. This proposal aims to elucidate the physiological functions of MVs derived from fermented-food bacteria and gut bacteria, and to develop immune adjuvants using these vesicles. We were able to elucidate the physicochemical, biochemical, and functional properties of MVs from L. plantarum and B. infantis. We were able to elucidate the mechanisms by which these MVs act on immune cells and intestinal epithelial cells. We identified proteins with an immune-stimulating activity from these MV fractions. We developed a culture medium that allows for the high-yield production of MVs. We developed high-producing strains of extracellular MVs through random mutagenesis.

Free Research Field

応用微生物学

Academic Significance and Societal Importance of the Research Achievements

腸内細菌が放出するMVsは、宿主の免疫賦活作用を示すため、ワクチンアジュバントへの応用が期待される。しかしMVsによって増強される免疫応答は不明であり、MVsによる宿主細胞への作用機序も不明である。MVsの生産機構は不明であり、免疫賦活能に優れたMVsの高生産株は育種されていない。MVsの活用には、これらの点を解明する必要があり、本研究成果はこれらの問題点の解決に寄与する。