Study on immunological mechanisms of the olfactory nervous system using viral infection models

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K21666
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 56:Surgery related to the biological and sensory functions and related fields
• Research Institution: National Institute of Infectious Diseases
• Principal Investigator: Nagata Noriyo 国立感染症研究所, 感染病理部, 室長 (30270648)
• Project Period (FY): 2020-07-30 – 2024-03-31
• Keywords: コクサッキーウイルス / SARS-CoV-2 / 嗅覚神経系 / マウスモデル

Outline of Final Research Achievements

The purpose of this study was to clarify the pathological lesions and host responses in the olfactory and central nervous systems after infection with respiratory viruses. We performed pathological comparative analysis of viral infection dynamics and immune responses in the upper respiratory tract, olfactory nervous system, and central nervous system of mice experimentally infected with coxsackievirus B2 and SARS-CoV-2. The immunohistochemical analysis revealed that each receptor molecule of the viruses in the murine upper respiratory tract was detected to be very different. Correspondingly, the localization and viral kinetics were different between two viruses. Coxsackievirus B2 invaded the murine olfactory bulb tissue, and histopathological examination clarified that viral spread was mainly prevented by microglia and astroglia cells.

Free Research Field

感染症の病理学

Academic Significance and Societal Importance of the Research Achievements

ヒトに上気道炎を引き起こすウイルスの中にはコクサッキーウイルス、エコーウイルス、あるいはH5N1インフルエンザなど神経向性を潜在的 に持つウイルスが多く存在し、その機構の解明は重要な課題であった。また、COVID-19の急性期のみならず罹患後の後遺症として嗅覚異常を訴える者は多いとされている。それぞれのウイルスの嗅覚組織におけるウイルス感染動態と免疫応答を明らかにすることで治療法・予防法の開発に貢献できると期待される。