{"id":273,"date":"2017-03-13T16:44:55","date_gmt":"2017-03-13T07:44:55","guid":{"rendered":"http:\/\/www2.med.osaka-u.ac.jp\/wwwmed\/eng\/activities\/research\/microbiology\/virology"},"modified":"2026-10-14T16:06:40","modified_gmt":"2026-10-14T07:06:40","slug":"virology_and_infectious_diseases","status":"publish","type":"page","link":"https:\/\/www.med.osaka-u.ac.jp\/eng\/introduction\/research\/microbiology\/virology_and_infectious_diseases","title":{"rendered":"Virology and Infectious Diseases"},"content":{"rendered":"<ul class=\"linkBar clearfix\"><!-- \n\n<li><a href=\"http:\/\/www.icb.med.osaka-u.ac.jp\/english\/index.html\" target=\"_blank\" rel=\"noopener\">Website<\/a><\/li>\n\n --><\/p>\n<li><a href=\"https:\/\/www.med.osaka-u.ac.jp\/introduction\/research\/microbiology\/virology_and_infectious_diseases\">Text in Japanese<\/a><\/li>\n<p><!-- \n\n<li><a href=\"#\" target=\"_blank\" class=\"pdf\" rel=\"noopener\">\u5927\u5b66\u9662\u751f\u5411\u3051\u7814\u7a76\u6982\u8981<\/a><\/li>\n\n --><\/ul>\n<div class=\"index\">\n<div class=\"title\">\u201cUncovering the Replication Strategies of Pandemic Viruses to Prepare for the Next Pandemic\u201d<\/div>\n<ul>\n<li>Elucidating the Replication Mechanism of SARS-CoV-2<\/li>\n<li>Elucidating the mechanisms of the immune response to pandemic viruses<\/li>\n<li>Research Aimed at HIV Cure<\/li>\n<li>Research on the Development of New Drugs for the Treatment of Hepatitis B Virus<\/li>\n<li>Elucidating the mechanisms of Influenza virus associated encephalopathy<\/li>\n<\/ul>\n<\/div>\n<p><!-- \/ .index --><\/p>\n<div class=\"profile\">\n<div class=\"clearfix\">\n<div class=\"fl photo\"><img decoding=\"async\" src=\"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-content\/uploads\/2026\/09\/miyauchi20261001.jpg\" alt=\"\" \/><\/div>\n<p><!-- \/ .photo --><\/p>\n<div class=\"name\"><span class=\"position\">Professor <\/span>Kosuke Miyauchi<\/div>\n<p><!-- \/ .name --><\/p>\n<div class=\"member\">Virology and Infectious Diseases<\/div>\n<p><!-- \/ .member --><\/p>\n<div class=\"description\">Laboratory for Virology at the Graduate School of Medicine, the University Osaka, is a laboratory with a long tradition that traces its roots back to Professor Koichi Yamanishi and had been carried on by Professor Keiji Ueda. In addition to continuing its research on herpes viruses and the hepatitis B virus, we are also actively conducting research on HIV-1, influenza viruses, and the SARS-CoV-2.<\/div>\n<p><!-- \/ .description --><\/div>\n<p><!-- \/ .clearfix --><\/div>\n<p><!-- \/ .profile --><\/p>\n<h3>Research for Replication Mechanism of SARS-CoV-2<br \/>Research for Mechanism of Immune Responses against Pandemic Viruses<\/h3>\n<p>Humankind continues to face the threat of pandemic viruses. Even in recent years\u2014such as the 2009 swine flu pandemic and the 2020 COVID-19 pandemic\u2014new viruses capable of infecting humans have emerged approximately every 10 years. Since humans have virtually no immunity to these pandemic viruses, the acquisition of neutralizing antibodies through newly developed vaccines is critical to bringing the pandemic under control. Furthermore, susceptibility to these pandemic viruses varies significantly depending on factors such as gender, age, and race; this is known to be based on differences in the dynamics of host factor proteins involved in viral replication. We study the mechanisms by which viruses replicate within the body and cause disease, as well as the mechanisms that induce immune responses against these viruses.<\/p>\n<h4><strong>Research for Replication Mechanism of SARS-CoV-2<\/strong><\/h4>\n<p>After binding to virus receptor, ACE2, SARS-CoV-2 invades host cells through the cleavage of a portion of viral spike protein by a host cell enzyme called TMPRSS2. It is known that TMPRSS2 is also required for the production of infectious particles of the influenza virus. We have discovered that TMPRSS2 acts as an inhibitor in the formation of infectious particles of SARS-CoV-2. Furthermore, we demonstrated that this inhibitory effect of TMPRSS2 is counteracted by the viral envelope protein. In other words, it has become clear that SARS-CoV-2 achieves efficient viral replication by utilizing the enzymatic activity of TMPRSS2 during cell entry and by suppressing TMPRSS2 activity\u2014which would otherwise interfere\u2014during viral particle formation.<sup>1)<\/sup><\/p>\n<p class=\"figure\"><img decoding=\"async\" class=\"imgC\" src=\"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-content\/uploads\/2026\/10\/miyauchi_eng_fig1.png\" alt=\"\" \/><\/p>\n<h4><strong>Research for Mechanism of Immune Responses against Pandemic Viruses<\/strong><\/h4>\n<p>Antibodies known as neutralizing antibodies, which inhibit viral entry, are crucial for protecting against viral infection. These neutralizing antibodies are produced by virus-specific B cells that recognize viral antigens, but this process requires the support of helper T cells. We are conducting research on helper T cells that support the production of neutralizing antibodies against influenza viruses and SARS-CoV-2.<sup>2)\u20134)<\/sup><br \/>We have established a system to isolate virus-specific immune cells from transgenic mice infected with viruses. By thoroughly elucidating which T cells and B cells are necessary for the production of virus-neutralizing antibodies, we aim to contribute to the development of novel vaccines capable of combating the next viral pandemic.<\/p>\n<p class=\"figure\"><img decoding=\"async\" class=\"imgC\" src=\"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-content\/uploads\/2026\/10\/miyauchi_eng_fig2.png\" alt=\"\" \/><\/p>\n<h4><strong>References<\/strong><\/h4>\n<p>1. Seki S et al EMBO Reports, 3424-3453. 2026<br \/>2. Khalil J et al. International Immunology, dxaf051. 2025<br \/>3. Miyauchi K et al. Nature Communications, June 18, 2021<br \/>4. Miyauchi K et al. Nature Immunology, 12: 1447\u20131458, 2016<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Text in Japanese \u201cUncovering the Replication Strategies of Pandemic Viruses to Prepare for the Next Pandemic\u201d  [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":75,"menu_order":180,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"_links":{"self":[{"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/pages\/273"}],"collection":[{"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/comments?post=273"}],"version-history":[{"count":10,"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/pages\/273\/revisions"}],"predecessor-version":[{"id":10171,"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/pages\/273\/revisions\/10171"}],"up":[{"embeddable":true,"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/pages\/75"}],"wp:attachment":[{"href":"https:\/\/www.med.osaka-u.ac.jp\/eng\/wp-json\/wp\/v2\/media?parent=273"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}