Research

Studying emerging viral infections and their pathogenesis

The Project Leader's Profile

Kazuyoshi Ikuta

Professor, Department of Virology, Research Center for Infectious Disease Control, Research Institute for Microbial Diseases, Osaka University

In 1973, graduated from Kobe University, Faculty of Agriculture.  
In 1975, completed the master course at the Graduate School of Science, Kobe University.  
In 1979, completed the doctoral course at the Graduate School of Medicine, Osaka University and obtained his Ph.D.  
In 1979, Research Associate in the Research Institute for Microbial Diseases, Osaka University and in 1989, appointed as Associated Professor in the same institute.  
In 1989, appointed as Professor in the Institute of Immunological Science, Hokkaido University.  Since 1998, he holds the current position.  
Specialized in Virology.  Since 4 years ago, he is mainly involved in the research on the emerging and re-emerging viral infections through collaboration with members in the Japan-Thailand Research Collaboration Center on Emerging and Re-emerging Infections (RCC-ERI).

Project Leader
  • Kazuyoshi Ikuta, Ph.D., Professor, Department of Virology, Research Institute for Microbial Diseases, Osaka University (RIMD-OU)
Research Members
  • Keizo Tomonaga, Associate Professor, Department of Virology, RIMD-OU
  • Akikazu Sakudo, Assistant Professor, Department of Virology, RIMD-OU
  • Yohei Watanabe, Postdoctoral Fellow, Department of Virology, RIMD-OU
  • Tomoyuki Honda, Postdoctoral Fellow, Department of Virology, RIMD-OU
  • Madiha S. Ibrahim, Postdoctoral Fellow, Department of Virology, RIMD-OU
  • Ritsuko Koketsu, Research Fellow, Department of Virology, RIMD-OU
  • Emi Tsukamoto, Research Fellow, Department of Virology, RIMD-OU
Research Collaborators
  • Takaaki Nakaya, Associate Professor, International Research Center for Infectious Diseases, RIMD-OU
  • Tomo Daidoji, Postdoctoral Fellow, International Research Center for Infectious Diseases, RIMD-OU
  • Masanori Kameoka, Associate Professor, Section of Viral Infections, RCC-ERI, RIMD-OU
  • Takeshi Kurosu, Assistant Professor, Section of Viral Infections, RCC-ERI, RIMD-OU
  • Yong-Gang Li, Postdoctoral Fellow, Section of Viral Infections, RCC-ERI, RIMD-OU
  • Yuta Kanai, Postdoctoral Fellow, Section of Viral Infections, RCC-ERI, RIMD-OU
  • Gui-Rong Bai, Postdoctoral Fellow, Section of Viral Infections, RCC-ERI, RIMD-OU
  • Uamporn Siripanyaphinyo, Postdoctoral Fellow, Section of Viral Infections, RCC-ERI, RIMD-OU

Summary

The research in this department focuses on several viruses as well as prion that target the immune, respiratory, or central nervous systems. We aim to understand the mechanisms for the replication and pathogenesis of such viral infections, as well as conducting the basic research to develop a possible effective control for those infections.

(1) Infections to the immune system (HIV, dengue virus)
We characterized the mechanism(s) by which HIV can establish persistent/latent infection and induce apoptosis, and identified host factors to be involved in the inhibition of HIV replication.  In addition, we identified plasma host factor, clusterin, by which dengue virus NS1 can interact, that could lead to a possible hypothesis for the mechanism of inducing dengue hemorrhagic fever.  

(2) Infections to the respiratory system (SARS-coronavirus, influenza virus)

SARS-CoV and influenza virus are typical agents to induce acute infectious diseases at the respiratory region.  We characterized the mechanism for its persistent infection and the mutation regions in the viral genome for the establishment of such infection.  In addition, we found a high susceptibility of human CD4+ T lymphocytes to H5N1 avian influenza virus.  Also, we characterized the virological aspects of H5N1 in Egypt.  For human influenza virus, we prepared several human monoclonal antibodies that neutralized wide-range of virus isolates.  

(3) Infections to the central nervous system (Borna disease virus, prion)
We first examined some epidemiological studies on Borna disease virus in Japan.  Also, we isolated the clinical virus from autopsied brain sample from a patient with schizophrenia and characterized the viral replication mechanism in the nuclei.  We also established the transgenic mouse model system for understanding the viral pathogenesis.  On the other hand, we examined the mechanisms for the infection and pathogenesis of PrPSc.  

(4) Food-borne infections (hepatitis E virus)
Among several agents to induce human hepatitis, hepatitis E virus (HEV) is the only virus to induce zoonosis through food-borne transmission.  We extensively characterized swine isolates of HEV in Japan.

(5) Blood-borne infections
We are working on the establishment of strategies to remove infectious agents that could be commonly contaminating the blood products such as parvovirus B19, HEV, and prion.

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Some of Recent Papers

  1. Yunoki, M., Urayama, T. and Ikuta, K. (2006). Possible removal of prion agents from blood products during the manufacturing process (review). Future Virol. 1, 659-674, 2006.
  2. Ohtaki, N., Kamitani, W., Watanabe, Y., Hayashi, Y., Yanai, H., Ikuta, K. and Tomonaga, K. (2007). Downregulation of an astrocyte-derived inflammatory protein, S100B, reduces vascular inflammatory responses in brains persistently infected with Borna diseases virus. J. Virol. 81, 5940-5948.
  3. Shoji-Kawata, S., Zhong, Q., Kameoka, M., Iwabu, Y., Sapsutthipas, S., Luftig, R.B. and Ikuta, K. (2007) The RING finger ubiquitin ligase RNF125/TRAC-1 down-modulates HIV-1 replication in primary human peripheral blood mononuclear cells. Virology 368, 191-204.
  4. Kurosu, T., Chaichana, P., Yamate, M., Anantapreecha, S., and Ikuta, K. (2007) Secreted complement regulatory protien clusterin interacts with dengue virus nonstructural protein 1. Biochem. Biophys. Res. Commun. 362, 1051-1056.
  5. Daidoji, T., Koma, T., Du, A., Yang, C.S., Ueda, M., Ikuta, K., and Nakaya, T. (2008) H5N1 avian influenza virus induces apoptotic cell death in mammalian airway epithelial cells. J. Virol. 82, 11294-11307.