Investigation of temperature-dependent bacterial virulence using cricket infection model

• Project/Area Number: 16K15274
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Bacteriology (including mycology)
• Research Institution: Okayama University (2018); The University of Tokyo (2016-2017)
• Principal Investigator: KAITO Chikara 岡山大学, 医歯薬学総合研究科, 教授 (60420238)
• Research Collaborator: SEKIMIZU kazuhisa
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000); Fiscal Year 2017: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2016: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: フタホシコオロギ / 温度依存性 / ヒト病原体 / LIPI-1 / 病原性真菌 / コオロギ / 高温 / 感染モデル / 無脊椎動物 / リステリア / 緑膿菌 / 黄色ブドウ球菌 / 温度 / 病原性 / 感染症

Outline of Final Research Achievements

Invertebrate animal infection models are suitable for screening biological molecules involved in infectious processes, because many times of infection experiments are possible. However, frequently-used invertebrate models such as silkworms, fruit flies, and nematodes cannot survive for a long time at 37 degree, and are not suitable for evaluating infectious processes at 37 degree, which is a human body temperature. In this study, we revealed that two-spotted cricket, a tropical insect, can be used as an infection animal model of human pathogen at 37 degree. Furthermore, we identified a gene involved in temperature-dependent killing activity of bacteria against animals by using the cricket infection model.

Academic Significance and Societal Importance of the Research Achievements

本研究は、フタホシコオロギを用いて、温度依存性の細菌の動物殺傷メカニズムの解明を可能とする動物感染モデルを確立した。本モデルを用いて、常温と３７度における感染プロセスを比較解析することにより、ヒト病原体の温度依存性の病原性メカニズムに関わる生体分子群を同定できる点で学術的意義がある。また、本モデルは温度依存性の細菌の病原性システムを標的とする薬剤の評価を可能とする点で、社会的意義がある。

Research Products

• [Journal Article] Two-spotted cricket as an animal infection model of human pathogenic fungi (2017)
  • Author(s): Kochi Yuto、Matsumoto Yasuhiko、Sekimizu Kazuhisa、Kaito Chikara
  • Journal Title: Drug Discoveries & Therapeutics Volume: 11 Issue: 5 Pages: 259-266
  • DOI: 10.5582/ddt.2017.01052
  • NAID: 130006210824
  • ISSN: 1881-7831, 1881-784X
  • Peer Reviewed / Open Access
• [Journal Article] A human pathogenic bacterial infection model using the two-spotted cricket, Gryllus bimaculatus (2016)
  • Author(s): Kochi, Y., Miyashita, A., Tsuchiya, K., Mitsuyama, M., Sekimizu, K., and Kaito, C.
  • Journal Title: FEMS Microbiol Lett Volume: 363 Issue: 15 Pages: fnw163-fnw163
  • DOI: 10.1093/femsle/fnw163
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Presentation] 熱帯性コオロギを用いたヒト病原性真菌の感染モデルの確立 (2016)
  • Author(s): 幸地悠斗、松本靖彦、関水和久、垣内力
  • Organizer: 第99回日本細菌学会関東支部総会
  • Place of Presentation: 北里大学（東京都 港区）
  • Year and Date: 2016-10-06
• [Presentation] 昆虫モデルを用いて解明する細菌の病原性発動システム (2016)
  • Author(s): 垣内力
  • Organizer: 第99回日本細菌学会関東支部総会
  • Place of Presentation: 北里大学（東京都 港区）
  • Year and Date: 2016-10-06
  • Invited
• [Presentation] コオロギを用いた細菌感染モデルの確立 (2016)
  • Author(s): 幸地悠斗、宮下惇嗣、関水和久、垣内力
  • Organizer: 第16回東京大学生命科学シンポジウム
  • Place of Presentation: 東京大学（東京都 目黒区）