A survey for Rat polyomavirus 2 in laboratory rats in Japan

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K14610
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 42040:Laboratory animal science-related
• Research Institution: Osaka Prefecture University
• Principal Investigator: Tanaka Miyuu 大阪府立大学, 生命環境科学研究科, 特任助教 (00756893)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Keywords: ラットポリオーマウイルス2 / 感染症 / 病理学 / 実験動物学 / 免疫不全ラット

Outline of Final Research Achievements

We revealed detailed pathology of Rat polyomavirus 2 (RatPyV2) in XSCID rats: histologically, we observed basophilic intranuclear inclusion bodies within epithelial cells in the salivary, Harderian, and extraorbital lacrimal glands, and in respiratory and reproductive tissues. It was suggested that the salivary glands were the most highly susceptible tissue to RatPyV2.In serological test, 46 in 121 immunocompetent rats (37.7%) were positive for RatPyV2. PCR test revealed that 41.1% (37/90 rats) immunocompetent rats were positive for RatPyV2 genes. Our survey for RatPyV2 revealed relatively widespread RatPyV2 infection in immunocompetent laboratory rat populations in Japan. We detected RatPyV2 genes in DNA samples including buccal swabs or blood smeared on the FTA cards (FTA-Amp method).The LAMP method could also detect RatPyV2 gene in XSCID rats. The FTA-Amp and LAMP method using buccal swabs could be useful for the rapid diagnosis of RatPyV2 infection.

Free Research Field

獣医病理学

Academic Significance and Societal Importance of the Research Achievements

現在、がん研究や再生医療研究、移植研究、創薬研究など医学・生命科学分野の研究を推進する上で、免疫不全ラットは必要不可欠なツールとなっている。一方で、日本の免疫正常ラット系統コロニー中には、RatPyV2 不顕性感染個体が一定の割合で存在することが明らかとなり、免疫不全ラットを用いた研究への影響が懸念される。我々が確立した、口腔内スワブを用いたFTA-Amp 法は、RatPyV2 感染症の簡便かつ迅速な診断法として有用であるのみならず、RatPyV2 不顕性感染個体を確実に検出する上でも、検査法としての有用性が期待される。