Study toward production for the next generation and precocious live vaccines against Cryptosporidium infections to control the calf diarrhea

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K19192
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 42:Veterinary medical science, animal science, and related fields
• Research Institution: Osaka Metropolitan University (2022-2023); Osaka Prefecture University (2021)
• Principal Investigator: Matsubayashi Makoto 大阪公立大学, 大学院獣医学研究科, 教授 (00321076)
• Co-Investigator(Kenkyū-buntansha): 松尾 智英 鹿児島大学, 農水産獣医学域獣医学系, 准教授 (50383667)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: クリプトスポリジウム / 寄生適応 / ゲノム解析 / 牛 / マウス

Outline of Final Research Achievements

In the present study, the objective is to analyze for production of the live vaccines to induce the protective mucosal immunity against the Cryptosporidium infections. Here, we obtained the Cryptosporidium isolate and inoculated to immunodeficient mice. Then, the obtained oocysts were passed through other mice, and this step was repeatedly conducted ten times so far. Consequently, the infectivity to the mice is increasing. Although further study is needed, there is a possibility that comparative whole genome analyses find the responsibility genes related to pathogenicity and host adaptation to different animal species including human.

Free Research Field

獣医寄生虫学

Academic Significance and Societal Importance of the Research Achievements

人、そして特に子牛において、クリプトスポリジウムによる下痢症の予防法、そして著効を示す治療薬は未だ開発されていない。本研究により、国内の病原株を他種動物に繰り返し継代することで、感染性が変化することを見出した。今後、これら株間での全ゲノム比較解析により、寄生性や病態、さらに寄生適応に関わる責任遺伝子を世界で初めて同定できる可能性がある。これらの結果は、将来、病原性を減弱させた弱毒生ワクチンの創出につながると期待される。