Parasitology Commons^™

Analyzing Antibody Immune Response In Α1,3galt-Ko Mice After Intranasal Vaccination Of Α-Gal Virus-Like Particle, Faith Brown

Honors Theses

In this study, we evaluated the immunogenicity of intranasal immunization with α-Gal-conjugated virus-like particles (VLPs) in an α1,3-galactosyltransferase-knockout (α1,3GalT-KO) mouse model that mimics the human immune response to the α-Gal epitope. The carbohydrate epitope galactose-α-1,3-galactose (α-Gal) is expressed on the cell surface of several pathogens, including Leishmania species. This molecule is absent in humans and has emerged as a promising immunogenic vaccine target. α1,3GalT-KO mice were intranasally immunized with 10 μg either Qβ-α-Gal or Qβ per nostril and boosted twice prior to sample collection. Blood and lung lavage samples were used to evaluate the antibody response. The Qβ-α-Gal group developed …

Spatially Resolved Transcriptomic Profiles Of Placental Cell Populations In Placental Malaria, Corina A. Mong

Undergraduate Honors Theses

Malaria remains a prevalent infectious disease that continues to cause disease-related morbidity and mortality. Despite preventative efforts, malarial pregnancies still cause birth complications, therefore emphasizing the necessity to study these adverse outcomes in malarial pregnancy. Malaria in pregnancy can lead to placental malaria (PM), which is the presence and accumulation of Plasmodium-infected red blood cells in the placental intervillous space (IVS). Even after treatment, past PM (presence of hemozoin crystals from the parasite in the placenta) can cause a chronic inflammatory response. We predicted that the activation states of the maternal monocytes and fetal macrophages differ within the placenta and …

Characterizing Malaria Infections In Caribbean Lizards: Parasite Niche Expansion & Host Response, Sarah J. Pangburn

Dissertations, Theses, and Capstone Projects

Malaria is historically one of the most severe parasitic human diseases and is still responsible for over half a million deaths annually. Plasmodium species, the causative agents of malaria, are often characterized by two hallmark features of their asexual stages: the invasion of vertebrate red blood cells and the presence of hemozoin pigment as a byproduct of host hemoglobin digestion. Despite their evolutionary relatedness to mammalian Plasmodium, wildlife malaria parasites are understudied, leaving their vast genetic diversity to be explored. Lizard-infective malaria parasites, for example, include over 100 species of Plasmodium and present a diverse array of phenotypes, some …

Morphometric And Molecular Characterization Of An Unpigmented Haemosporidian Parasite In The Neotropical Turnip-Tailed Gecko (Thecadactylus Rapicauda), Nubia E. Matta, Leydy P. González, Mario Vargas-Ramírez, Gediminas Valkiūnas, Ananias A. Escalante, M. Andreína Pacheco

Harold W. Manter Laboratory of Parasitology: Library Materials

Morphological traits from blood stages have been the gold standard for determining haemosporidian parasite species. However, the status of some taxa and the value of such traits in parasites from reptiles remain contentious. The scarce sampling of these species worsens the situation, and several taxa lack molecular data. A survey was performed in the Magdalena Department in Colombia, where 16 species of reptiles were captured. A peculiar haemosporidian parasite was found in the Turnip-tailed gecko Thecadactylus rapicauda. This haemosporidian does not show malarial pigment in blood stages under light microscopy; thus, it fits the Garnia genus’s characters belonging to …

Complexity Of Malaria Transmission Dynamics In The Brazilian Atlantic Forest, Ana Maria Ribeiro De Castro Duarte, Licia Natal Fernandes, Fabiana Santos Silva, Igor Lucoves Sicchi, Luis Filipe Mucci, Izilda Curado, Aristides Ferrnandes, Antônio Ralph Medeiros-Sousa, Walter Ceretti-Junior, Mauro Toledo Marrelli, Eduardo Evangelista, Renildo Teixeira, Juliana Laurito Summa, Marcello Schiavo Nardi, Margoth Ramos Garnica, Ana Carolina Loss, Julyana Cerqueira Buery, Crispim Cerutti Jr., M. Andreína Pacheco, Ananias A. Escalante, Maria Anice Mureb Sallum, Gabriel Zorello Laporta

Harold W. Manter Laboratory of Parasitology: Library Materials

Plasmodium malariae and Plasmodium vivax are protozoan parasites that can cause malaria in humans. They are genetically indistinguishable from, respectively, Plasmodium brasilianum and Plasmodium simium, that is, parasites infecting New World non-human primates in South America. In the tropical rainforests of the Brazilian Atlantic coast, it has long been hypothesized that P. brasilianum and P. simium in platyrrhine primates originated from P. malariae and P. vivax in humans. A recent hypothesis proposed the inclusion of Plasmodium falciparum into the transmission dynamics between humans and non-human primates in the Brazilian Atlantic tropical rainforest. Herein, we assess the occurrence of human …

Plasmodium Impairs Antibacterial Innate Immunity To Systemic Infections In Part Through Hemozoin-Bound Bioactive Molecules., Christopher Lynn Harding

Electronic Theses and Dissertations

Despite efforts to decrease the global health burden of malaria, infections with Plasmodium species continue to cause over 200 million episodes of malaria each year which resulted in 405,000 deaths in 2018 [1]. One complication of malaria is increased susceptibility to invasive bacterial infections. Plasmodium infections impair host immunity to non-Typhoid Salmonella (NTS) through activities of heme oxygenase I (HO-I) )-induced release of immature granulocytes and myeloid cell-derived IL-10. Yet, it is not known if these mechanisms are specific to NTS. We show here, that Plasmodium yoelii 17XNL (Py) infected mice had impaired clearance of systemic Listeria monocytogenes (Lm) during …

The Nuclear 18s Ribosomal Dnas Of Avian Haemosporidian Parasites, Josef Harl, Tanja Himmel, Gediminas Valkiūnas, Herbert Weissenböck

Harold W. Manter Laboratory of Parasitology: Library Materials

Background: Plasmodium species feature only four to eight nuclear ribosomal units on different chromosomes, which are assumed to evolve independently according to a birth-and-death model, in which new variants originate by duplication and others are deleted throughout time. Moreover, distinct ribosomal units were shown to be expressed during different developmental stages in the vertebrate and mosquito hosts. Here, the 18S rDNA sequences of 32 species of avian haemosporidian parasites are reported and compared to those of simian and rodent Plasmodium species.

Methods: Almost the entire 18S rDNAs of avian haemosporidians belonging to the genera Plasmodium (7), Haemoproteus (9), …

Plasmodium Para-Aminobenzoate Synthesis And Salvage Resolve Avoidance Of Folate Competition And Adaptation To Host Diet, Joachim Michael Matz, Mutsumi Watanabe, Mofolusho Falade, Takayuki Tohge, Rainer Hoefgen, Kai Matuschewski

Pharmaceutical Sciences Faculty Publications

Folate metabolism is essential for DNA synthesis and a validated drug target in fast-growing cell populations, including tumors and malaria parasites. Genome data suggest that Plasmodium has retained its capacity to generate folates de novo. However, the metabolic plasticity of folate uptake and biosynthesis by the malaria parasite remains unresolved. Here, we demonstrate that Plasmodium uses an aminodeoxychorismate synthase and an aminodeoxychorismate lyase to promote the biogenesis of the central folate precursor para-aminobenzoate (pABA) in the cytoplasm. We show that the parasite depends on de novo folate synthesis only when dietary intake of pABA by …

The Polyphyly Of Plasmodium: Comprehensive Phylogenetic Analyses Of The Malaria Parasites (Order Haemosporida) Reveal Widespread Taxonomic Conflict, Spencer C. Galen, Janus Borner, Ellen S. Martinsen, Juliane Schaer, Christopher C. Austin, Christopher J. West, Susan L. Perkins

Harold W. Manter Laboratory of Parasitology: Library Materials

The evolutionary relationships among the apicomplexan blood pathogens known as the malaria parasites (order Haemosporida), some of which infect nearly 200 million humans each year, has remained a vexing phylogenetic problem due to limitations in taxon sampling, character sampling and the extreme nucleotide base composition biases that are characteristic of this clade. Previous phylogenetic work on the malaria parasites has often lacked sufficient representation of the broad taxonomic diversity within the Haemosporida or the multi-locus sequence data needed to resolve deep evolutionary relationships, rendering our understanding of haemosporidian lifehistory evolution and the origin of the human malaria parasites incomplete. Here …

A Multivariate Approach For An Improved Assessment Of Pre-Erythrocytic Stage Therapies Targeting Plasmodium Vivax And Plasmodium Falciparum, Alison E. Roth

USF Tampa Graduate Theses and Dissertations

The malaria pre-erythrocytic stages have been identified as an ideal therapeutic target, but complex in vitro models for Plasmodium vivax and Plasmodium falciparum lack the efficiency needed for rapid screening and evaluation of new vaccines and drugs, especially targeting the P. vivax hypnozoite. To address this challenge, we employed a multi-parameter approach using “omics’” to identify pre-erythrocytic targets and biomarkers, guide phenotypic therapeutic screening, and study parasite functionality with innovative bioassays using highcontent screening. Herein, we discuss three novel bioassays formatted in 384-well plate systems with utilization of commercially-available materials and application of high-content imaging for rapid bio-image analysis. To …

Do Avian Blood Parasites Influence Hypoxia Physiology In A High Elevation Environment?, Farah Ishtiaq, Sahas Barve

Biological Sciences Faculty Publications

BACKGROUND: Montane birds which engage in elevational movements have evolved to cope with fluctuations in environmental hypoxia, through changes in physiological parameters associated with blood oxygen-carrying capacity such as haemoglobin concentration (Hb) and haematocrit (Hct). In particular, elevational migrants which winter at low elevations, encounter varying intensities of avian haemosporidian parasites as they traverse heterogeneous environments. Whilst high intensity parasite infections lead to anaemia, one can expect that the ability to cope with haemosporidian infections should be a key trait for elevational migrants that must be balanced against reducing the oxygen-carrying capacity of blood in response to high elevation. In …

Mode And Rate Of Evolution Of Haemosporidian Mitochondrial Genomes: Timing The Radiation Of Avian Parasites, M. Andreína Pacheco, Nubia E. Matta, Gediminas Valkiūnas, Patricia G. Parker, Beatriz Mello, Craig E. Stanley Jr., Miguel Lentino, Maria Alexandra Garcia-Amado, Michael Cranfield, Sergei L. Kosakovsky Pond, Ananias A. Escalante

Harold W. Manter Laboratory of Parasitology: Library Materials

Haemosporidians are a diverse group of vector-borne parasitic protozoa that includes the agents of human malaria; however, most of the described species are found in birds and reptiles. Although our understanding of these parasites’ diversity has expanded by analyses of their mitochondrial genes, there is limited information on these genes’ evolutionary rates. Here, 114 mitochondrial genomes (mtDNA) were studied from species belonging to four genera: Leucocytozoon, Haemoproteus, Hepatocystis, and Plasmodium. Contrary to previous assertions, the mtDNA is phylogenetically informative. The inferred phylogeny showed that, like the genus Plasmodium, the Leucocytozoon and Haemoproteus genera are not monophyletic groups. Although …

Antimalarial Exoerythrocytic Stage Drug Discovery And Resistance Studies, Lynn Dong Blake

USF Tampa Graduate Theses and Dissertations

Malaria is a devastating global health issue that affects approximately 200 million people yearly and over half a million deaths are caused by this parasitic protozoan disease. Most commercially available drugs only target the blood stage form of the parasite, but the only way to ensure proper elimination is to treat the exoerythrocytic stages of the parasite development cycle. There is a demand for the discovery of new liver stage antimalarial compounds as there are only two current FDA approved drugs for the treatment of liver stage parasites, one of which fails to eliminate dormant forms and the other inducing …

Local Parasite Lineage Sharing In Temperate Grassland Birds Provides Clues About Potential Origins Of Galapagos Avian Plasmodium, Iris I. Levin, Rachel E. Colborn, Daniel Kim, Noah G. Perlut, Rosalind B. Renfrew, Patricia G. Parker

Environmental Studies Faculty Publications

Oceanic archipelagos are vulnerable to natural introduction of parasites via migratory birds. Our aim was to characterize the geographic origins of two Plasmodium parasite lineages detected in the Galapagos Islands and in North American breeding bobolinks (Dolichonyx oryzivorus) that regularly stop in Galapagos during migration to their South American overwintering sites. We used samples from a grassland breeding bird assemblage in Nebraska, United States, and parasite DNA sequences from the Galapagos Islands, Ecuador, to compare to global data in a DNA sequence registry. Homologous DNA sequences from parasites detected in bobolinks and more sedentary birds (e.g., brown-headed cowbirds …

Identification And Characterization Of Interactors Of Plasmodium Falciparum Pfpk6, An Atypical Protein Kinase, Andi J. Cummins

Honors Undergraduate Theses

Plasmodium falciparum, the organism that causes the most prevalent and most virulent cases of malaria in humans, poses a major health burden on the developing world, especially in the tropical regions of Sub-Saharan Africa, Southeast Asia, and Latin America. The burden of the disease is intensified by the fact that the parasite has developed widespread resistance to all current antimalarial therapies, such as chloroquine. This drug resistance underscores the need to develop novel therapeutics that target the parasite, but show low toxicity in the human host. Protein kinases, because of their integral roles in cell signaling networks, are considered to …

Molecular Evolution And Phylogenetics Of Rodent Malaria Parasites, Ricardo S. Ramiro, Sarah E. Reece, Darren J. Obbard

Harold W. Manter Laboratory of Parasitology: Library Materials

Background: Over the last 6 decades, rodent Plasmodium species have become key model systems for understanding the basic biology of malaria parasites. Cell and molecular parasitology have made much progress in identifying genes underpinning interactions between malaria parasites, hosts, and vectors. However, little attention has been paid to the evolutionary genetics of parasites, which provides context for identifying potential therapeutic targets and for understanding the selective forces shaping parasites in natural populations. Additionally, understanding the relationships between species, subspecies, and strains, is necessary to maximize the utility of rodent malaria parasites as medically important infectious disease models, and for …

The Evolutionary Host Switches Of Polychromophilus: A Multi-Gene Phylogeny Of The Bat Malaria Genus Suggests A Second Invasion Of Mammals By A Haemosporidian Parasite, Fardo Witsenburg, Nicolas Salamin, Philippe Christe

Harold W. Manter Laboratory of Parasitology: Library Materials

Background: The majority of Haemosporida species infect birds or reptiles, but many important genera, including Plasmodium, infect mammals. Dipteran vectors shared by avian, reptilian and mammalian Haemosporida, suggest multiple invasions of Mammalia during haemosporidian evolution; yet, phylogenetic analyses have detected only a single invasion event. Until now, several important mammal-infecting genera have been absent in these analyses. This study focuses on the evolutionary origin of Polychromophilus, a unique malaria genus that only infects bats (Microchiroptera) and is transmitted by bat flies (Nycteribiidae).

Methods: Two species of Polychromophilus were obtained from wild bats caught in Switzerland. These …