Laboratory of Viral Infection I

¡¡Our laboratory focuses on basic research into a viral vaccine, antiviral drugs, and antiseptics to control viral infections and regulate viral diseases. Our main research targets are a norovirus, sapovirus, rotavirus and astrovirus that cause viral gastroenteritis.

¡¡Human norovirus (HuNoV) is a major cause of winter acute gastroenteritis. It causes food poisoning in more than 120 million people each year worldwide. In developing countries, approximately 200,000 children are estimated to die annually of HuNoV-mediated diarrhea. Control of HuNoV outbreaks by disinfectants, vaccination or antiviral drugs is needed. However, the lack of cultivability, undefined cellular targets, and also no animal model of HuNoV have hindered direct research into HuNoV.

¡¡Our research group successfully developed a reverse genetics system (RGS) for HuNoV and murine norovirus (MNV). In particular, the RGS produces progeny MNV viruses that can infect a susceptible cell line. Thus, we can manipulate norovirus genome and study viral replication and how pathogenicity is expressed. Furthermore, we initiated a search of the NoV replication inhibitors and for sensitive cell by incorporating reporter genes, such as GFP or the luciferase, into the viral genes (PNAS 11: E4043-52, 2014). Our research group also found MNV functional proteinous receptor molecules CD300lf and CD300ld, using a CRISPER/Cas9 genome-wide gene knock-out system (PNAS 113: E6248-55, 2016).

¡¡Recently, a HuNoV culture system that uses the intestinal organoid system was reported. The discovery of a HuNoV culture system is a breakthrough for the study of noroviruses and other gastroenteritis viruses. Now, our research group is investigating HuNoV receptor molecule, viral replication and pathogenicity using new molecular biological and structure biological technologies with excellent collaborations with other scientists in different disciplines.

¡¡We work in several research areas.

1. Development of new vaccine platform using structural biological study protocol (a collaboration with Tokyo Institute of Technology and the National Institute of Infectious Diseases).
2. Research and development (a collaboration with Tokyo Institute of Technology and the National Institute of Infectious Diseases) of a vaccine for human gastroenteric viruses.
3. Studies of the mechanisms of how the gastroenteric viruses, such as the norovirus, proliferate and of antiviral drugs.
4. Studies of the viral receptor and of construction of a proliferative culture system of the gastroenteritis virus using the intestinal organoid (in collaboration with Keio University and Baylor College of Medicine)
5. Molecular epidemiology studies (in collaboration with Nagoya City University and the National Institute of Infectious Diseases) that aim to predict the outbreak of a gastroenteritis virus by elucidating its mechanism of the outbreak.
6. Fundamental research to develop a new vaccine using a chimeric virus of a measles virus and the RS virus.