Molecular Phylogenetics, Diagnostics and Control of Apicomplexan Parasites

我的研究计划的长期目标是在历史、有机体（宿主-寄生虫）和分子水平上探索和理解顶复合体门寄生虫与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；我们将通过从感染家养宿主和大部分被忽视的野生宿主的顶复体寄生虫中获取序列数据（核18S rDNA、质体rDNA/聚合酶B和mt细胞色素c氧化酶亚基I， COI）来确定人类、家养动物和野生动物（潜在的人畜共患病）的顶复体寄生虫的生物多样性。我们新开发的PCR引物对将产生基于coi的物种特异性DNA条形码，用于特异性识别球虫（艾美耳虫），包括肠道（如艾美耳虫）和组织（如弓形虫）球虫。我们将修改我们的DNA条形码引物，用于多重NGS检测，以鉴定和枚举生物样品（如粪便或组织样品）中的混合球虫；这种方法将允许快速发现原生寄生虫的生物多样性和物种；***2)*生成具有生物多样性的*顶复合体寄生虫的完整线粒体（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的进化史所需的序列数据。***3)探讨家禽球虫的免疫控制。我们将在国内和国际上确定感染家养火鸡的艾美耳球虫的自然流行率，以确定针对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重组多价疫苗技术，该技术将两个寄生虫抗原表位与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结构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。

The*long term goal of my research program is to explore and understand the interactions between*parasites of the phylum Apicomplexa and their hosts at the historical,*organismal (host-parasite) and molecular levels. These parasites cause*important animal and human diseases such as malaria, toxoplasmosis,*cryptosporidiosis and coccidiosis. I propose to further our understanding of*these relationships by pursuing three main areas of study:***1) Investigate apicomplexan phylogeny and host-parasite coevolution*using multi genome molecular markers with morphological and morphometric*characters: We will determine the biodiversity of apicomplexan parasites in*humans, domesticated animals and wildlife (potential zoonotics) by generating*sequence data (nuclear 18S rDNA, plastid rDNA/polymerase B, and mt cytochrome c oxidase subunit I, COI) from*apicomplexan parasites that infect both domestic and, largely ignored, wildlife*hosts. Our newly developed PCR primer pairs will generate species-specific*COI-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 NGS*assay to both identify and enumerate mixed coccidia in biological samples such*as fecal or tissue samples; this method will permit rapid protistan parasite*biodiversity and species discovery;***2)*Generate complete mitochondrial (mt) genomes from biologically diverse*apicomplexan parasites to explore the structural evolution of mt genomes and*generate sequence data necessary for inferring the evolutionary history of*these cosmopolitan parasites.***3) Explore immunological control of coccidia of domestic poultry. We*will determine*the natural prevalence of Eimeria that infect domestic turkeys*nationally and internationally to determine the number of species required in a*multivalent live coccidiosis vaccine against turkey coccidiosis. We will refine and further develop a recombinant*multivalent vaccine technology that combines two parasite antigenic epitopes with a*host-derived immune modulating epitope (HMGB1). *The current Bacillus subtilis expression vector for this multivalent*vaccine construct will be converted into a strictly peptide based (i.e.*chemically synthesized) form and tested for biological activity in vivo when*delivered by various means.