新疆马泰勒虫病地方流行虫株致病机理及蜱传播媒介效能和机制研究

Xinjiang is the largest province of breeding horses in China, and the horse industry has broad prospects. However, the distribution of vector tick species accounted for two-thirds of the country, 80% of the horses bited by ticks, and were infected with tick-borne Theileria equi per year, resulting in anemia, jaundice, hemoglobinuria, asphyxia, parasitaemia and death in horses, serious harm and there are no effects of drugs and vaccines until now. In this study, we choose the T. equi and vector ticks based on the previous study, for the vector efficiency of ticks carrying the pathogen biodiversity, and ecological relevance with T. equi, as well as nosogenesis of regional epidemic strain, systematic study on the high, multiple and serious harm of T. equi by molecular biology methods of the etiology and immunology. For vector efficiency of ticks infected with T. equi, carrying pathogenic virulence and its transmission mechanism, and biology relationship with host horses, and nosogenesis of parasite etc. To obtain the biological characteristics data of ticks vector efficiency and the regional strain of T.equi,we established the culture techniques in vitro and pathogen database, constructed the recombinant plasmid GFP-RAP, clarified the invasion character of T. equi, discovered the nosogenesis of T. equi and transmission mechanism of ticks vector efficiency, thus decrease and eliminate infectious disease, reducing economic losses, provide a scientific basis for integrated control of the disease, and promote the healthy development of modern horse industry in Xinjiang.

新疆是我国养殖马匹数量最多的省区，马产业前景广阔，蜱分布种类占全国的2/3，每年有80%的马匹被蜱叮咬发生蜱传马泰勒虫病，导致马匹贫血、黄疸、血红蛋白尿、窒息及虫血症而死亡，危害严重，目前尚无特效药物和疫苗。本研究在前期工作基础上，以马泰勒虫及媒介蜱为研究对象，对蜱携带病原的生态多样性的媒介效能，与马泰勒虫的生态关联性，及地方流行虫株致病机理等科学问题，采用病原学、免疫分子生物学等方法，系统研究高发多发、危害严重的马泰勒虫病即我区马泰勒虫病媒介蜱的感染效能、携带病原毒力及传播机制、与宿主马匹之间的生物学关系和致病机理等，获得蜱媒介效能生物学特性数据和马泰勒虫地方虫株；建立体外培养技术及病原数据库；构建GFP-RAP重组质粒，阐述马泰勒虫入侵宿主特性；揭示马泰勒虫致病机理及蜱媒介效能的传播机制，降低或消除该病的传染、减轻经济损失，为该病的综合防治提供科学依据，促进新疆特色现代马产业健康发展。

本研究团队自项目申报以来，深入基层到伊犁哈萨克自治州昭苏马场、巴音郭楞蒙古自治州焉耆马场、哈密地区伊吾马场、阿勒泰地区放牧马场和克孜勒苏柯尔克孜自治州散养马场等5个示范地蹲点进行跟踪采集样品，共计采集马匹体表、马厩和环境中的蜱虫50200只，疑似马血液样品40500匹份。分别采用病原学、免疫学、分子生物学以及流行病学调查等方法，系统研究了传播马泰勒虫的优势媒介蜱种、媒介蜱的感染效能和携带病原情况，以及马泰勒虫病的流行规律和相关因素，及其入侵相关靶基因功能，旨在揭示马泰勒虫与宿主马匹之间的生物学相关性关系。此外我们分离了马泰勒虫流行虫株，并建立了体外培养体系、病原数据库和防治规程等，为马蜱传原虫病的综合防控奠定了基础。本研究对采集的样品进行了病原的分离和鉴定，已成功获得了新疆马主产区优势蜱种和传播马泰勒虫病的优势媒介蜱分布物种，共计革蜱属4种、璃眼蜱属2种，首次验证了边缘革蜱可“经卵传播”马泰勒虫的生物学特性；构建了马泰勒虫18s基因系统进化树以及虫体入侵宿主红细胞特性相关的RAP和 EMA 抗原基因质粒，并成功表达靶蛋白，经实验研究发现RAP 系列蛋白对马泰勒虫入侵宿主红细胞至关重要，阐述了马泰勒虫入侵宿主的特性，并获得了地方虫株和标准虫株的基因差异性数据；以昆明小鼠为动物模型成功扩繁、分离了马泰勒虫昭苏流行虫株（Te-Y）；建立了马泰勒虫In vitro 初始培养体系，镜检发现虫体呈典型的逗点或梨子型，共计传代6次，染虫率在3.0~5.4%；从不同试验示范点采集的血样中成功分离出3个马泰勒虫流行虫株；撰写了马泰勒虫病综合防治规程并在示范区应用，取得明显的社会和经济效益。项目实施以来共计发表学术论文20余篇，其中SCI收录4篇，申报专利2项，行业及地方标准4项，培养博士后/博士/硕士研究生10人。综上所述，本项目的实施及完成为我区马产业的健康发展和区域性经济发展提供了科学参考依据。