Immunology and Infectious Disease Commons^™

Characterizing The Interaction Between Human Adenovirus E1a And Sting, Jessica Hill

Electronic Thesis and Dissertation Repository

When challenged by viral DNA, the cytoplasmic DNA sensor cyclic GMP-AMP synthase (cGAS) signals through the adaptor protein stimulator of interferon genes (STING) to induce a primary type I IFN response. Studies from recent years have also revealed shared architecture between metabolism and innate immunity. Viruses have evolved to counteract these mechanisms. Human adenovirus (HAdV) early region 1A (E1A) protein antagonizes the cGAS-STING pathway to prevent an innate immune response by physically interacting with STING. I hypothesize that the interaction between E1A and STING is mediated through several motifs and involves ribosomal protein S6 kinase beta-1 (S6K1). Using a series …

Changing Antimalarial Drug Sensitivities In Uganda, Stephanie Alexis Rasmussen

Dissertations, Masters Theses, Capstones, and Culminating Projects

Dihydroartemisinin-piperaquine (DP) has demonstrated excellent efficacy for the treatment and prevention of malaria in Uganda. However, resistance to both components of this regimen has emerged in Southeast Asia. The efficacy of artemether-lumefantrine, the first-line regimen to treat malaria in Uganda, has also been excellent, but continued pressure may select for parasites with decreased sensitivity to lumefantrine. To gain insight into current drug sensitivity patterns, ex vivo sensitivities were assessed and genotypes previously associated with altered drug sensitivity were characterized for 58 isolates collected in Tororo, Uganda from subjects presenting in 2016 with malaria from the community or as part of …

Mechanism Of Candida Albicans Biofilm And Virulence Inhibition By A Bacterial Secreted Factor, Carrie Graham

Dissertations & Theses (Open Access)

The human microbiome is a diverse polymicrobial population comprised of both fungi and bacteria. Perturbations of the normal microbiome can have a profound impact on health, including the development of infections. Exploitation of these polymicrobial interactions has the potential to provide novel treatment and prevention strategies for infectious diseases. Enterococcus faecalis, a Gram-positive bacterium, and Candida albicans, a polymorphic fungus, occupy overlapping niches as ubiquitous constituents of the gastrointestinal and oral microbiome. Both species are also amongst the most important and problematic, opportunistic nosocomial pathogens and are often co-isolated during infection. Surprisingly, these two species antagonize each other’s …

Type Ix Secretion System : Characterization Of An Effector Protein And An Insight Into The Role Of C-Terminal Domain Dimeration In Outer Membrane Translocation., Lahari Koneru

Electronic Theses and Dissertations

Porphyromonas gingivalis and Tannerella forsythia are two of the primary pathogens that are associated in the etiology and progression of chronic periodontitis. In T. forsythia, KLIKK proteases are the recently identified group of proteolytic enzymes that are secreted through Type IX secretion system (T9SS). Among, these KLIKK proteases a synergistic relationship was observed between karilysin and mirolysin in invading the host complement system for the survival of the bacteria. Since, karilysin has been already characterized, in this study we propose to study about mirolysin through structural, biochemical and biological characterization. The obtained results from the experiments has shown the …

Evaluation Of A Microsphere-Based Immunoassay (Mia) In Measuring Diagnostic And Prognostic Markers Of Dengue Virus Infection, Jason H. Ambrose

USF Tampa Graduate Theses and Dissertations

Infections with dengue viruses (DENV) constitute both a global problem as well as locally in Florida. DENV comprise four distinct serotypes of single-stranded RNA viruses and belong to the family Flaviviridae. DENV are among the most medically important arboviruses in the world and cases may currently exceed 400 million per annum. Additionally, dengue established its first recorded endemic transmission cycle in the state of Florida in over a half century, first within the Florida Keys during 2009-10 followed by an unrelated outbreak in Martin County in 2013. The clinical profile of DENV infections ranges from a mild febrile illness …

Role Of Viruses Within Metaorganisms: Ciona Intestinalis As A Model System, Brittany A. Leigh

USF Tampa Graduate Theses and Dissertations

Marine animals live and thrive in a literal sea of microorganisms, yet are often able to maintain specific associations that are largely dictated by the environment, host immunity and microbial interactions. Animal-associated microbiomes include bacteria and viruses that vastly outnumber host cells, especially in the gut environment, and are considered to be integral parts of healthy, functioning animals that act as a metaorganism. However, the processes underlying the initial establishment of these microbial communities are not very well understood. This dissertation focuses on the establishment of a well-known developmental animal model, Ciona intestinalis (sea squirt), to study the establishment and …

Trypanosome Lytic Factor Mediated Immunity Against Leishmania Sp., Jyoti Pant

Dissertations, Theses, and Capstone Projects

Trypanosome Lytic Factor (TLF) is an innate immunity complex that was originally discovered to protect against African Trypanosomes. The major components of TLF are Apolipoprotein A1 (APOA1), Apolipoprotein L1 (APOL1) and HPR (Haptoglobin Related Protein), where APOL1 is necessary and sufficient for trypanolysis. Recently we have shown that TLF ameliorates infections by cutaneous Leishmania species. Here we investigated the effect of different primate and human TLF against different Leishmania sp. Our result shows that TLF kills metacyclic promastigotes of cutaneous Leishmania sp. within immune cells such as neutrophils and macrophages by two different mechanism. Using transiently transfected and germline transgenic …

Redirection Of The Immune Response To Staphylococcus Aureus Biofilm Infection, Anna G. Staudacher

Theses & Dissertations

Staphylococcus aureus (S. aureus) is a leading cause of community- and healthcare-associated infections and has a propensity to form biofilms. Biofilm infections are recalcitrant to host immune-mediated clearance as well as antibiotics, making them exceptionally difficult to eradicate. The biofilm environment has been shown to skew the host immune response towards an anti-inflammatory phenotype, characterized by alternatively activated macrophages, recruitment of myeloid-derived suppressor cells (MDSCs), and minimal neutrophil and T cell infiltrates. Our laboratory has attempted to redirect the host immune response towards one that would favor bacterial clearance by employing strategies to augment pro-inflammatory mechanisms. One such …

Antiviral Nucleoside Inhibitors Of Leishmania Rna Virus 1: Discovery And Mechanism, John Isaac Robinson

Arts & Sciences Electronic Theses and Dissertations

Some Leishmania parasites in the Viannia sub-genus are persistently infected with Leishmania RNA virus 1 (LRV1), a single-segmented double-stranded RNA virus belonging to the family Totiviridae. Infected parasites cause greater pathology and reach higher populations in mouse models of Leishmania infection. In human disease, LRV1+ parasites are correlated with increased frequency of treatment failure and relapse. Efficient methods to detect LRV1 and eliminate it from parasites are required to better understand the role of LRV1 in Leishmania infection. We optimized multiple techniques to measure LRV1 levels in parasites, most notably using flow cytometry to measure the amount of viral capsid …

Identification And Characterization Of An Interferon Stimulated Gene That Restricts Alphavirus Infection And Pathogenesis, Subhajit Poddar

Arts & Sciences Electronic Theses and Dissertations

Viral infection of host cells induces the Type I interferon (IFN) response, which is

characterized by the production of hundreds of IFN-stimulated genes (ISGs). Altogether, these

ISGs function to induce an antiviral state, hindering or blocking various steps of the viral

lifecycle. Many individual ISGs have potent and broad antiviral functions. However elimination

of a single ISG does not completely abrogate protection, suggesting that other ISGs, although

moderate or moderate when considered alone, must work cooperatively to provide optimal

antiviral activity.

In order to identify and characterize novel ISGs, an attenuated strain of the alphavirus

chikungunya (CHIKV-181/25) was tested against …

Expansion Of Microbial Virology By Impetus Of The Reduction Of Viral Dark Matter, Siddharth Ravindran Krishnamurthy

Arts & Sciences Electronic Theses and Dissertations

Modern metagenomic methods have rapidly accelerated the rate of viral discovery. Currently, to discover a novel virus, deep sequencing reads must align to a known reference virus. While alignment is effective at identifying closely related viruses, highly divergent viruses can often share no discernable sequence alignment with known viruses. Therefore, the accurate classification of viral dark matter – metagenomic sequences that originate from viruses but do not align to any reference virus sequences – is one of the major obstacles in not only discovering novel viruses, but also by extension, comprehensively defining the virome. As viral dark matter results fundamentally …

Expression Profiling Of Non-Coding Rna By Environmental Interactions In Innate Immunity, Jacob R. Longfellow

Electronic Theses and Dissertations

Cystic fibrosis (CF) is a genetic disorder that affects 30,000 people in the United States and currently has no cure. Although CF affects all of the body’s systems, it is largely characterized as a lung disease. CF is caused by a mutation in both copies of the gene for cystic fibrosis transmembrane conductance regulator (CFTR). A mutation in the CFTR gene leads to improper movement of chloride ions and water into the airways, which dysregulates the airway surface liquid volume and composition. Individuals with CF are prone to lung infections due to inefficient bacterial clearance and by the age of …

The Role Of Rna Interference In The Control Of Leishmania Rna Virus 1 Infection, Erin Acino Brettmann

Arts & Sciences Electronic Theses and Dissertations

The presence of Leishmania RNA virus 1 (LRV1) in parasites of the Leishmania (Viannia) subgenus increases the virulence of the parasite in mouse models of leishmaniasis and is correlated with treatment failure, relapse, and the development of mucocutaneous disease in humans. LRV1 is not shed or infectious; rather, the infection is persistent, and as yet it is unknown how the parasite controls virus levels. Many eukaryotic organisms use RNA interference (RNAi) to limit virus replication, and Leishmania (Viannia) parasites have an active RNAi pathway. To determine whether Leishmania are capable of using RNAi to control LRV1, we sequenced sRNAs from …

The Role Of Bhlhe40 In Autoimmune Neuroinflammation And Mycobacterial Infection, Chih-Chung Lin

Arts & Sciences Electronic Theses and Dissertations

The mammalian immune system is composed of innate and adaptive compartments, which cooperate with each other to maintain homeostasis and protect the host from the invasion by a variety of pathogens. The tight control of immune responses is extremely important for all individuals. Here, we discovered that the transcription factor basic helix-loop-helix family, member e40 (Bhlhe40) is a critical protein that regulates the autoimmune ("against self") and anti-microbial ("against non-self") responses of myeloid cells and T lymphocytes. Multiple sclerosis (MS) is a human neuroinflammatory disease in the central nervous system with an autoimmune etiology. We have reported that Bhlhe40 positively …

The Role Of Histidine Rich Protein Ii In Cerebral Malaria, Priya Pal

Arts & Sciences Electronic Theses and Dissertations

Human malaria is caused by five species of Plasmodium. Of these, P. falciparum is the deadliest and is the only species that causes cerebral malaria (CM). CM is a disease of the vascular endothelium characterized by parasite sequestration, increased inflammatory cytokine production, vascular leakage and leukocyte infiltration. A distinguishing feature of P. falciparum infection is the parasite’s production and secretion of histidine-rich protein II (HRPII). HRPII accumulates to high concentrations (up to 100 µg/ml) in serum, which correlates with disease severity. Due to high serum levels of this protein, HRPII has classically been considered a biomarker for P. falciparum infection. …

Toll Like Receptor 4 Stimulation Increases Scavenger Receptor A Expression On Murine Macrophages, Mackenzie L. Guthrie

Undergraduate Honors Theses

Sepsis is the body’s response to an overwhelming infection and is a serious consequence of critical illness. It can cause tissue damage, organ failure, and death. Sepsis continues to have an unacceptably high mortality rate, due to the lack of effective treatments. Specific therapeutic targets for sepsis remain elusive since the complex functional changes that result in a septic state remain poorly understood. Macrophage Scavenger Receptor A (SRA, CD204) is a surface receptor that binds negatively charged, endogenous and exogenous ligands. We have discovered that SRA plays a significant role in the pathophysiology of sepsis. We have shown that mice …

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …

Elucidating The Role Of Interleukin-17a In West Nile Virus Infection, Dhiraj Acharya

Dissertations

West Nile virus (WNV) is a neurotropic flavivirus of significant public health importance for which no therapeutics and vaccine are currently available. Interleukin-17A (IL-17A) is an inflammatory cytokine that regulates diverse immune functions, while its role is unclear in host’s immune response to WNV. Furthermore, CD8⁺ T cells are crucial components of immunity and play a vital role in recovery from WNV infection. Here, we report a previously unrecognized function of IL-17A in regulating CD8⁺ T cell cytotoxicity. We show that WNV induces the expression of IL-17A in both mouse splenocytes and human peripheral blood mononuclear cells cultured …

Study Of Rickettsia Parkeri Colonization And Proliferation In The Tick Host Amblyomma Maculatum (Acari: Ixodidae), Khemraj Budachetri

Dissertations

Amblyomma maculatum (Gulf coast tick) ticks are prevalent across the Atlantic to Gulf Coast region of United States. These ticks are recognized vectors of Rickettsia parkeri, a spotted fever group of Rickettsia (SFGR) known to cause American boutonneuse fever associated with fever and eschar rashes localized to the site of bites. We hypothesized that Rickettsia parkeri colonization and proliferation in the tick vector involve pathogen-symbiont dynamics and tick-pathogen interactions, which influence rickettsial transmission to the victims after tick bites. The rickettsial infection is maintained across the tick life cycle for many generations due to transovarial and transstadial transmission of …

Function Of The Enterobactin Operon Of A. Actinomycetemcomitans In The Presence Of Catecholmines And Iron., Taylor Johnson

Electronic Theses and Dissertations

Background: Aggregatibacter actinomycetemcomitans (Aa) possesses a two-component system, QseBC, which is key in biofilm formation/virulence and is activated in the presence of iron-catecholamine complexes. Aa does not synthesize enterobactin, a catechol-based siderophore, yet possesses the machinery for recognition and uptake. We hypothesize that Aa is able to acquire iron by catecholamine mediation through the enterobactin receptor/transporter. Methods: By insertional mutation, we attempted to delete the enterobactin permease from the genome using suicide vector pJT1. A growth curve of truncated mutant ΔfepA was also conducted to observe growth in the presence of iron and catecholamines. Statistical significance was determined by ANOVA …

The Neonatal Anti-Viral Response Fails To Control Measles Virus Spread In Neurons Despite Interferon-Gamma Expression And A Th1-Like Cytokine Profile, Priya Ganesan

Electronic Theses and Dissertations

Neonates are highly susceptible to infections in the central nervous system (CNS) and have a greater risk of viral infections and encephalopathies. Neurotropic viral infections can lead to blindness, hearing loss and neurological deficiencies such as cognitive impairment, epilepsy, and even death in the neonatal and pediatric populations. Viral infections also are hypothesized to indirectly contribute to neurodegenerative and neuropsychiatric diseases such as Schizophrenia and Parkinson’s disease later in life due to early neuronal damage or stress. Many diverse viruses are capable of invading the neonatal CNS including Borna Disease Virus, Coxsackievirus (CV), Herpes simplex viruses (HSV), and measles virus. …

A Novel Molecular Relationship Between Parn And Pld That, When Deregulated, Contributes To The Aggressive Phenotype Of Breast Cancer Cell Lines., Taylor Elaine Miller

Browse all Theses and Dissertations

The removal of mRNA transcript poly(A) tails by 3'-5' exonucleases is the rate-limiting step for controlled mRNA decay in eukaryotes. Poly(A)-specific ribonuclease (PARN) is one such exonuclease that degrades poly(A) tails, and although its in vitro activity is well-characterized, PARN’s patho-physiological roles in the cell are not well understood. Prior studies have found a possible role for PARN in cancer, in that PARN expression levels in human breast cancer tissues are often decreased compared to normal control tissues. Indeed, data mined from the ONCOMINE cancer array database showed that PARN is downregulated in patient invasive breast carcinoma samples compared to …

Genomic Vs. Non-Genomic Role Of The Ahr In Human Immunoglobulin Expression, Nasser Alhamdan

Browse all Theses and Dissertations

The immunoglobulin heavy chain gene (Igh) in various animal models is regulated by numerous regulatory elements including the 3’Igh regulatory region (3’IghRR). Several transcription factors are involved in modulating the 3’IghRR including the aryl hydrocarbon receptor (AhR). The AhR is a ligand-activated transcription factor that mediates the transcription of genes involved in the metabolism of environmental toxicants such as TCDD. TCDD binds AhR and regulates immunoglobulin (Ig) expression in B cells. This modulation appears to be directly mediated by binding of the AhR to dioxin response elements (DRE) within the 3’IghRR. In human B cells, IgG secretion inhibited by TCDD …

Effects Of Socs1 And Socs3 Peptide Mimetics On Macrophage Phagocytosis Of Malignant Cells, Colt Dylan Capan

Browse all Theses and Dissertations

Macrophages play a key role in both the innate and adaptive immune system responses to foreign materials. Suppressors of cytokine signaling (SOCS) proteins are known as regulators of the immune response through various JAK/STAT pathways. This study examined the roles of SOCS1 and SOCS3 peptide mimetics on the phagocytosis of fluorescently labeled malignant target cell by RAW264.7 murine macrophages. The malignant cells used were Neuro-2a cells, a murine neuroblastoma cell line. A prominent “eat me” signal found in neuroblastoma cells is calreticulin (CRT), which permits macrophages to recognize and then phagocytize the malignant cells. When M1 (pro-inflammatory) polarized macrophages were …

Development And Characterization Of Histidine-Tagged Hpv16 L2 And Ms2-Arginine-Tagged Recombinant Proteins For Downstream Processes, Tahiyat Alothaim

Dissertations, Master's Theses and Master's Reports

Human papillomaviruses (HPVs) are the most common sexually transmitted infections. Persistent infection with HPV can lead to anogenital cancers including head and neck cancers. Three prophylactic vaccines have been approved to prevent against some types of HPV infection. However, the vaccines are HPV-type specific and protect mostly against the HPV types included in the vaccines. To offer broader protection against more HPV types, studies in the field are developing candidate vaccines targeting a conserved minor capsid protein, L2. Nevertheless, reagents for developing and assessing L2 vaccines are limited. For example, antibodies to assess the antigenicity of some L2 epitopes are …

Orientia Tsutsugamushi Secretes Two Ankyrin Repeat-Containing Effectors Via A Type 1 Secretion System To Inhibit Host Nf-Κb Function, Sean M. Evans

Theses and Dissertations

Scrub typhus is a potentially fatal infection that threatens one billion persons in the Asia-Pacific region and is caused by the obligate intracellular bacterium, Orientia tsutsugamushi. How this organism facilitates its intracellular survival and pathogenesis is poorly understood. Intracellular bacterial pathogens utilize the Type 1 (T1SS) or Type 4 secretion system (T4SS) to translocate ankyrin repeat-containing proteins (Anks) into the host cell to modulate host cell processes. The O. tsutsugamushi genome encodes one of the largest known bacterial Ank libraries as well as Type 1 and Type 4 secretion systems (T1SS and T4SS), which are expressed during infection. In …

Vitamin D3 And Suppressor Of Cytokine Signaling Proteins Reduces Pro-Inflammatory Cytokines In An Alzheimer's Disease Like-Model Consisting Of Microglial And Neuronal Co-Cultures, Alexander Evdokiou

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This study examined the inflammatory effects of amyloid-beta (A[beta]42) in a microglial-neuronal co-culture system and determined whether 1a, 25-dihydroxyvitamin D3 (1,25-(OH)2D3) along with suppressor of cytokine signaling (SOCS)1 and SOCS 3 mimetics would attenuate the inflammatory response to A[beta]42. This culture system, when seeded with A[beta]42, serves as an in vitro model for Alzheimer's disease (AD). In a neuronal-microglia co-culture, A[beta]42 stimulated microglia to secrete TNF-a, but with the addition of 1,25-(OH)2D3, TNF-a levels dropped by nearly eight-fold and to near zero values in the presence of both 1,25-(OH)2D3 and SOCS1 and SOCS 3 mimetics. The reduction of the inflammatory …

Using Extremophile Bacteriophage Discovery In A Stem Education Professional Development Partnership To Explore Model Classroom Research Experiences Integrating The Three Dimentions Of The Next Generation Science Standards, Carrie L. Boudreau Ms

All Student Scholarship

The National Research Council’s (NRC) A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas describes a vision of what it means to be proficient in science. The project discussed in this thesis was developed with a NIH SEPA Grant 8R25OD010937 to the Virology and Electron Microscopy Laboratory at the University of Southern Maine (USM) under the direction of Dr. S. Monroe Duboise. The goal of the project was to explore using discovery of extreme environment bacteria and their bacteriophages as a model for using the three dimensions of learning to teach Next Generation Science Standards (NGSS). Specifically, …

Role Of Intracellular Growth During The Gastrointestinal Stage Of Listeria Monocytogenes Infection, Grant Steven Jones

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Listeria monocytogenes is a facultative intracellular bacterium that causes foodborne disease in humans. L. monocytogenes invade the gut mucosa and then disseminate, causing systemic infections associated with high mortality rates in immunocompromised individuals. It is unknown how L. monocytogenes traffic to the mesenteric lymph nodes, which represent an important bottleneck for systemic spread. In addition, little is known about the gastrointestinal stage of infection due to the general resistance of mice to oral infection with L. monocytogenes. Our laboratory developed a novel foodborne mouse model of listeriosis utilizing a murinized strain of L. monocytogenes to investigate the gastrointestinal stage …

Genetic Interference And Receptor Biology Of Neglected Influenza Viruses, Runxia Liu

Electronic Theses and Dissertations

Influenza B virus (IBV) is an important pathogen that infects humans and causes seasonal influenza epidemics. By using next-generation sequencing (NGS) approach, we analyzed total mRNAs extracted from A549 cells infected with B/Brisbane/60/2008, and identified four defective genomes in IBV with two from the polymerase basic subunit 1 (PB1) segment and the other two from the matrix (M) segment. Each of them can potently inhibit the replication of IBV. One derived from PB1 segment was able to interfere modestly with influenza A virus (IAV) replication. The productions of the four defective RNAs are not dependent on the cell types. The …