National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan; Division of Collaboration and Education, Hokkaido University Research Center for Zoonosis Control, Sapporo, Hokkaido 001-0020, Japan.
National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan.
Int J Parasitol. 2018 Oct;48(12):915-924. doi: 10.1016/j.ijpara.2018.05.012. Epub 2018 Aug 31.
Oriental theileriosis caused by Theileria orientalis is an economically significant disease in cattle farming. The lack of laboratory animal models and in vitro culture systems is a major obstacle in the drive to better understand the biology of this parasite. Notably, research on the sporozoite stage of T. orientalis has rarely been undertaken, although such investigations are of paramount importance for vaccine development based on blocking sporozoite invasion of its host animals. In the present study, we established a mouse-tick infection model for propagating T. orientalis in mice and for producing the sporozoite stage in tick salivary glands. Splenectomized severe combined immunodeficient mice transfused with bovine erythrocytes were infected with T. orientalis. The larval ticks of Haemaphysalis longicornis were then fed on the T. orientalis-infected mice. The piroplasm and sporozoite stages were microscopically observed in the mouse blood and nymphal salivary glands, respectively. The transcriptomics data generated from the piroplasm and sporozoite stages revealed a stage-specific expression pattern for the parasite genes. The mouse-tick infection model and the transcriptomics data it has provided will contribute to a better understanding of T. orientalis biology and will also provide much needed information for the design of effective control measures targeting oriental theileriosis.
东方泰勒虫病由东方泰勒虫引起，是畜牧业中一种具有重要经济意义的疾病。缺乏实验室动物模型和体外培养系统是深入了解这种寄生虫生物学的主要障碍。值得注意的是，尽管基于阻断疟原虫入侵宿主动物的疫苗开发的研究非常重要，但对东方泰勒虫的裂殖体阶段的研究很少进行。在本研究中，我们建立了一种小鼠-蜱感染模型，用于在小鼠中繁殖东方泰勒虫，并在蜱的唾液腺中产生裂殖体阶段。用牛红细胞输注脾切除术严重联合免疫缺陷小鼠感染东方泰勒虫。然后用感染了东方泰勒虫的小鼠来喂养长角血蜱的幼虫。在小鼠血液和若虫唾液腺中分别用显微镜观察到血孢子虫和裂殖体阶段。来自血孢子虫和裂殖体阶段的转录组学数据显示寄生虫基因具有特定阶段的表达模式。该小鼠-蜱感染模型及其提供的转录组学数据将有助于更好地了解东方泰勒虫的生物学，并为设计针对东方泰勒虫病的有效控制措施提供急需的信息。
