Molecular Phylogenetics, Diagnostics and Control of Apicomplexan Parasites

我的研究计划的长期目标是探索和了解顶复合体门寄生虫与宿主在历史，有机体（宿主-寄生虫）和分子水平上的相互作用。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。我建议通过三个主要研究领域来进一步了解这些关系：1)利用具有形态学和形态计量学特征的多基因组分子标记来研究顶复合体的系统发育和宿主-寄生虫的共同进化；我们将通过生成序列数据（核18S rDNA、质体rDNA/聚合酶B和细胞色素c氧化酶亚基I， COI）来确定顶复体寄生虫在人类、家养动物和野生动物（潜在的人畜共患病）中的生物多样性。顶复体寄生虫感染家养动物和大部分被忽视的野生动物宿主。我们新开发的PCR引物对将产生基于物种特异性coi的DNA条形码，用于特异性识别球虫（艾美耳球虫），包括肠道（如艾美耳球虫）和组织（如弓形虫）球虫。我们将修改我们的DNA条形码引物，用于多路NGSassay，以识别和枚举生物样本（如粪便或组织样本）中的混合球虫；该方法可以快速发现原生寄生虫的生物多样性和物种；2)从生物多样性的顶复体寄生虫中生成完整的线粒体基因组，探索线粒体基因组的结构进化，并生成推断这些世界性寄生虫进化史所需的序列数据。3)探讨家禽球虫的免疫控制。我们将确定国内和国际上感染火鸡的艾美耳球虫的自然流行率，以确定用于火鸡球虫病的多价活球虫疫苗所需的种数。我们将完善并进一步开发一种结合两种寄生虫抗原表位和宿主源性免疫调节表位（HMGB1）的重组多价疫苗技术。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以肽为基础（即化学合成）的形式，并通过各种方式在体内测试生物活性。

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.