Molecular Phylogenetics, Diagnostics and Control of Apicomplexan Parasites

顶复门寄生虫的分子系统发育、诊断和控制

• 批准号: RGPIN-2016-05826
• 负责人: Barta, John
• 金额: $ 2.4万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=761919
• 关键词: Molecular; Phylogenetics; Diagnostics; Control; Apicomplexan

Thelong term goal of my research program is to explore and understand the interactions betweenparasites of the phylum Apicomplexa and their hosts at the historical,organismal (host-parasite) and molecular levels. These parasites causeimportant animal and human diseases such as malaria, toxoplasmosis,cryptosporidiosis and coccidiosis. I propose to further our understanding ofthese relationships by pursuing three main areas of study:1) Investigate apicomplexan phylogeny and host-parasite coevolutionusing multi genome molecular markers with morphological and morphometriccharacters: We will determine the biodiversity of apicomplexan parasites inhumans, domesticated animals and wildlife (potential zoonotics) by generatingsequence data (nuclear 18S rDNA, plastid rDNA/polymerase B, and mt cytochrome c oxidase subunit I, COI) fromapicomplexan parasites that infect both domestic and, largely ignored, wildlifehosts. Our newly developed PCR primer pairs will generate species-specificCOI-based DNA barcodes that will be used to identify specifically coccidia(Eimeriorina) including enteric (e.g. Eimeria)and tissue (e.g. Toxoplasma)coccidia. We will modify our DNA barcode primers for use in a multiplexed NGSassay to both identify and enumerate mixed coccidia in biological samples suchas fecal or tissue samples; this method will permit rapid protistan parasitebiodiversity and species discovery;2)Generate complete mitochondrial (mt) genomes from biologically diverseapicomplexan parasites to explore the structural evolution of mt genomes andgenerate sequence data necessary for inferring the evolutionary history ofthese cosmopolitan parasites.3) Explore immunological control of coccidia of domestic poultry. Wewill determinethe natural prevalence of Eimeria that infect domestic turkeysnationally and internationally to determine the number of species required in amultivalent live coccidiosis vaccine against turkey coccidiosis. We will refine and further develop a recombinantmultivalent vaccine technology that combines two parasite antigenic epitopes with ahost-derived immune modulating epitope (HMGB1). The current Bacillus subtilis expression vector for this multivalentvaccine construct will be converted into a strictly peptide based (i.e.chemically synthesized) form and tested for biological activity in vivo whendelivered by various means.

我的研究计划的长期目标是在历史、生物(寄主-寄生虫)和分子水平上探索和了解尖端寄生虫门的寄生虫与它们的宿主之间的相互作用。这些寄生虫引起重要的动物和人类疾病，如疟疾、弓形虫病、隐孢子虫病和球虫病。我建议通过以下三个主要研究领域来加深我们对这些关系的理解：1)使用具有形态和形态特征的多基因组分子标记来研究复合顶体寄生虫的系统发育和宿主-寄生虫的共同进化：我们将通过从感染家养和基本上被忽视的野生动物宿主的顶复联体寄生虫产生序列数据(核18S rDNA、质体rDNA/聚合酶B和线粒体细胞色素C氧化酶亚基I，COI)来确定人类、驯养动物和野生动物(潜在的人畜共栖动物)中顶端复合体寄生虫的生物多样性。我们新开发的聚合酶链式反应引物对将生成特定物种的基于COI的DNA条形码，用于识别球虫(如艾美尔球虫)，包括肠道球虫(如艾美耳球虫)和组织球虫(如弓形虫)。我们将修改我们的DNA条形码引物，用于多重NGS分析，以识别和计数生物样本(如粪便或组织样本)中的混合球虫；该方法将有助于快速检测原生寄生虫的生物多样性和物种发现；2)从生物多样性的顶端复合体寄生虫中产生完整的线粒体(MT)基因组，以探索mt基因组的结构进化，并生成推断这些世界性寄生虫进化史所需的序列数据。3)探索家禽球虫的免疫控制。我们将确定感染国内和国际火鸡的艾美耳球虫的自然流行率，以确定对抗火鸡球虫病的多价球虫病活疫苗所需的种类数量。我们将完善和进一步开发一种重组多价疫苗技术，将两个寄生虫抗原表位和一个宿主来源的免疫调节表位(HMGB1)结合起来。目前用于这种多价疫苗构建的枯草芽孢杆菌表达载体将被转化为严格基于多肽的形式(即化学合成)，并在体内进行生物活性测试，然后通过各种方法进行传递。