Development of practical and effective immersion nanovaccines against bacterial fish diseases using novel nanomaterials

2023 Fiscal Year Final Research Report

• Project/Area Number: 17K07922
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Aquatic bioproduction science
• Research Institution: Tokoha University (2020-2023); Numazu National College of Technology (2018-2019); Ube National College of Technology (2017)
• Principal Investigator: Mitome Noriyo 常葉大学, 教育学部, 准教授 (90431981)
• Project Period (FY): 2017-04-01 – 2024-03-31
• Keywords: ナノワクチン / 魚病 / 外膜タンパク質 / 抗原

Outline of Final Research Achievements

The pathogenic marine bacterium, Edwardsiella tarda, causes the fatal disease, edwardsiellosis, in fish. Owing to the unavailability of a commercial vaccine to prevent infection or the spread of the disease in fish stock, fish farms suffer huge losses during edwardsiellosis outbreaks. Nanovaccines require specific antigens, such as the bacterial outer membrane proteins (OMPs) carried around and inside nanoparticles, to act as vaccines. We developed a rapid and inexpensive method for the isolation and purification of OMPs from marine bacteria and demonstrated the antigenicity of the purified OMPs using Koi carp. The purified OMPs were then incorporated into the nanoparticles to generate a nanovaccine. Nanovaccinated Koi carp produced antibodies against the OMPs of E. tarda. We propose that the nanovaccines techniques are simple to apply and effective to prevent disease outbreaks in fish farms.

Free Research Field

生化学

Academic Significance and Societal Importance of the Research Achievements

不活化微生物ワクチンや生物由来のベクターでなく、中空針状の形状のナノチューブをワクチンのベクターとして利用し、実用的な水産用の浸漬ナノワクチンを開発した。このナノチューブの容量は小さいため、これをワクチンのベクターとするために、不活化微生物ではなく、微生物の表面に存在する抗原性タンパク質を調製して、ナノチューブに封入した。本研究では実用化を目指して、抗原性タンパク質を迅速に安価でスケールアップが容易な精製方法を開発した。ナノワクチンは、注射法と違って、浸漬法により手間と時間をかけずに一度に数万匹の魚やサイズの小さい魚でも接種させることができるため、水産業への応用が期待される。