Molecular Phylogenetics, Diagnostics and Control of Apicomplexan Parasites

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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. Successful*vaccination against Eimeria species using a non-viable vaccine construct (a*global first) would address vaccine production, transportation and shelf life*issues as well as avoid health implications of using live coccidiosis vaccines*in commercial poultry.**