Study of innate immune responses against viral infection

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H03480
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 49060:Virology-related
• Research Institution: Kumamoto University
• Principal Investigator: Oshiumi Hiroyuki 熊本大学, 大学院生命科学研究部(医), 教授 (50379103)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 自然免疫 / ウイルス / インターフェロン

Outline of Final Research Achievements

Innate immune response is a first line of defense against viral infection, whereas its excessive activation leads to autoimmune disorders and cytokine storm. Thus, the innate immune system should be tightly regulated. However, its underlying mechanisms are not fully elucidated. We have investigated the molecular mechanisms of antiviral innate immune responses. We identified ZNF598 as a negative regulator of cytokine expression during viral infection. The blood contains high concentration of extracellular vesicles (EVs), including exosomes and microvesicles, that carry immune regulatory microRNAs. We found that miR-451a and miR-192 within the EVs regulate the cytokine expression in response to viral infection or vaccination with seasonal flu whole virus vaccines. Moreover, we investigated the molecular mechanism of innate immune responses against SARS-CoV-2 and found that the two genome RNA regions of SARS-CoV-2 were preferentially recognized by cytoplasmic viral RNA sensors.

Free Research Field

免疫学

Academic Significance and Societal Importance of the Research Achievements

新型コロナウイルス感染症のように、ウイルスが原因となる感染症はその解決が求められている。その解決として、ワクチンや治療薬の開発が求められている。本研究ではウイルス感染に対する自然免疫の分子機構について研究を進め、新たなメカニズムを解明し、これらに関与する新たな因子としてのタンパク質やmicroRNAを複数同定した。本研究で解明した新たな分子メカニズムは、今後、ウイルス感染症に対する新たなワクチンの開発や、新たな治療薬の開発、さらに、新たな治療法の開発の重要な基礎基盤になると期待される。