Elucidation of house dust mite-induced intestinal epithelial barrier dysfunction in the development of chronic enteropathy in dogs

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K08099
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Veterinary medical science
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: Ohmori Keitaro 東京農工大学, (連合)農学研究科(研究院), 講師 (20466915)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: ハウスダストマイト / 犬 / 慢性腸症 / サイトカイン

Outline of Final Research Achievements

House dust mite (HDM) is an environmental allergen ubiquitously present indoors, causing allergic inflammation in dogs. However, whether HDM allergens are detected in the gastrointestinal (GI) tract of dogs and their contribution to the development of chronic enteropathy (CE) remain unclear. The purposes of this study were to determine the presence of HDM allergens in the GI tract of dogs with CE, and to elucidate the effect of HDM on IL-1beta and NLRP3 expression in canine macrophages. HDM allergens were detected in the gastric and duodenal fluids of laboratory healthy dogs and dogs with CE and feces of all dogs examined. HDM allergens in the duodenal and colonic mucosae were significantly higher in dogs with CE than in laboratory healthy dogs. HDM induced expressions of nlrp3 and il-1beta mRNA and IL-1beta protein in canine macrophages. HDM allergens present in the GI tract may be involved in the pathogenesis of CE, promoting IL-1beta expression in the intestinal mucosa.

Free Research Field

臨床獣医学

Academic Significance and Societal Importance of the Research Achievements

環境アレルゲンであるHDMは、健常犬および慢性腸症の犬を含め、家庭で飼育されている犬に幅広く経口摂取されるが、腸上皮バリア機能が減弱した慢性腸症の犬の腸粘膜では、HDMアレルゲンが腸粘膜内に侵入し、腸粘膜に存在するマクロファージのNLRP3インフラマソームを活性化することでIL-1betaの産生を誘導する可能性が明らかになった。本研究により、HDMが慢性腸症の犬の消化管において、自然免疫系を活性化することで慢性的な腸炎を発症させる新たな病態が明らかになった。