Disease Modeling Commons^™

Orchestrated Architecture Dismantling: Borrelia Burgdorferi’S Coordinated Destruction Of Adaptive Immune Responses, Craig A. Land

Electronic Theses and Dissertations

Borrelia burgdorferi represents the most prevalent vector-borne bacteria in North America, affecting ~476,000 Americans annually yet persisting despite robust immune responses. This project reveals spirochetes target adaptive immunity through coordinated lymphatic colonization and precision immune dysregulation.

Using comparative host models (C57BL/6 vs. reservoir Peromyscus leucopus), we demonstrate lymph node colonization within 48-hours, with spirochetes exploiting LYVE-1-positive lymphatic structures as dissemination highways while avoiding the interior of follicular regions. Critically, we identify targeted CD4+ T-cell elimination in germinal center border zones at 21-DPI, precisely when these cells should be coordinating protective immunity. Concurrent upregulation of inhibitory receptor CD32b creates molecular …

Advancing Research On Retinitis Pigmentosa: An Investigation Of Natural History, Visual System Plasticity, And Mutation-Independent Treatment., Cecilia A. Attaway

Electronic Theses and Dissertations

Retinitis Pigmentosa (RP) is an inherited retinal disease characterized by rod and then cone photoreceptor degeneration. ~25% of cases are caused by a genetic mutation that results in autosomal dominant RP (adRP). There has been a lack of exploration of the progression of degeneration in adRP models. In Chapter Two, I examined visual acuity (VA) changes, retinal structure, and function from early to late-stage disease in a murine P23H Rho ‘knock-in’ mouse model (Rho^P23H/+), the most common form of adRP in North America. To establish a natural history, I evaluated behavioral VA, using the visual water task, …

Air-Jet Bioprinting Of Stem Cell-Encapsulated Alginate Micro-Droplets For Organoid Biomanufacturing, Mirabella B. Stump

Electronic Theses and Dissertations

Biomanufactured 3D-organoids show promise for modeling and treating various conditions, particularly insulin-dependent diabetes mellitus (type-1 diabetes). Pancreatic islet organoids serve as sustainable sources of insulin-producing β-cells, potentially restoring insulin regulation in patients and providing a long-term solution for diabetes. Hydrogel droplet printing is an emerging technique in regenerative medicine due to its advantageous tunability and biocompatibility; however, challenges of consistency, quality control, and scalability persist. To address these issues, we developed a novel air-jetting based droplet bioprinting system for the generation of monodispersed alginate micro-droplets. The objective of this project was to incorporate human induced pluripotent stem cells (hiPSCs) into …

Ethanol Dysregulates Sirt1-Mediated Lipogenic Signaling Pathways Through Α4*-Nicotinic Acetylcholine Receptors In Hepatocytes., Caitlin Christina Wilkerson

Electronic Theses and Dissertations

Alcohol-associated liver disease (ALD) is a broad spectrum of diseases ranging from steatosis to severe hepatic cirrhosis, none of which have any FDA approved therapies. Downregulation of hepatic Sirtuin 1 (Sirt1) activity by ethanol has been shown to lead to an upregulation of the pro-lipogenic gene targets under its jurisdiction, resulting in increased lipogenesis and triglyceride accumulation. It was hypothesized that ethanol acts on α4*-nicotinic acetylcholine receptors (α4*-nAChRs) in hepatocytes to decrease Sirt1 expression, which ultimately dysregulates lipid metabolic homeostasis. Ethanol’s effects were investigated in cultured AML12 hepatocytes and in WT primary mouse hepatocytes acutely exposed to ethanol. Consistent with …

Investigating The Effects Of Subchronic Dietary Zinc Supplementation On Diet-Induced Metabolic Dysfunction-Associated Steatotic Liver Disease., Oluwanifemi Esther Bolatimi

Electronic Theses and Dissertations

Zinc deficiency is associated with metabolic dysfunction-associated steatotic liver disease (MASLD). Previous studies show zinc supplementation improves steatosis, but its therapeutic effects in established MASLD remain unclear. We developed a model to characterize the effects of zinc supplementation on high-fat diet (HFD) induced MASLD and hypothesized established MASLD would be attenuated. Mice were fed control diet or HFD for 12 weeks and then grouped into normal or zinc-supplemented diets for 8 additional weeks. At euthanasia, plasma and liver tissues were collected for phenotypic analysis. Twelve weeks of HFD altered glucose clearance and body composition. Eight weeks of subsequent zinc supplementation …

Species Data And Vector Modeling: Evaluating Datasets For Improved Models Of Ixodes Ricinus Tick Distribution In Europe Under A Changing Climate, Steven Jones

Electronic Theses and Dissertations

To increase capacity for monitoring and surveillance of tick-borne diseases, publicly available tick distribution and climate change datasets are required to create accurate predictive distribution models. It is difficult, however, to assess model accuracy and utility when using incomplete datasets.  The more recent development of comprehensive tick databases for Europe and availability of climate change scenarios from multiple IPCC Assessment Reports allows for improved modeling efforts. Multiple tick datasets were combined and three climate change projections were compared by predicting current and future distributions of Ixodes ricinus ticks in Europe using the MaxEnt species distribution model. Overall, much of Europe …

An Application Of Differential Mathematical Modeling Techniques To Study The Ongoing Rabies Epizootic In China, Christopher Turner

Electronic Theses and Dissertations

Rabies remains a global public health issue with a wide variety of neurological symptoms such as confusion, slight paralysis, hypersalivation, and hydrophobia. Rabies is usually fatal once symptoms appear. Many species are reservoirs for rabies, such as foxes, racoons, and wild dogs, which in turn can transmit the disease to humans, leading to complex transmission chains. There is a long latent period of rabies, between 1 to 3 months after infection, which further complicates control efforts. Mathematical modeling is a valuable tool in the study of infectious disease outbreaks and there have been many models applied to rabies outbreaks. However, …

Cannabinoids And Retinal Fibrotic Disorders., Lucy June Sloan

Electronic Theses and Dissertations

Retinal fibrosis is detrimental to vision. Retinal pigment epithelial (RPE) cells contribute to several retinal fibrotic diseases. Upon exposure to TGF-β, a key fibrotic cytokine, RPE cells trans-differentiate to myofibroblasts marked by the integration of α-SMA fibers into F-actin stress fibers, which confer strong contractility. Myofibroblasts produce and contract the collagen-rich fibrotic scar and disrupt retinal architecture. In this study, we investigated the in vitro effects of the putative endocannabinoid compound N-oleoyl dopamine (OLDA) on TGF-β2 induced porcine RPE cell contraction and α-SMA expression. Using an in vitro collagen matrix contraction assay, we found that OLDA inhibited TGF-β2 induced contraction …

Genetic And Functional Analysis Of Rat Mammary Cancer Susceptibility., Emily L Duderstadt

Electronic Theses and Dissertations

Breast cancer genetic susceptibility is modulated by high to low penetrance risk alleles. Population frequencies of high and moderate penetrant predisposing mutations are rare and responsible for a small percentage of population cases. Most genetic variation in breast cancer susceptibility is low penetrance common variants where causal genes and risk-associated mechanisms are largely unknown. Comparative genetics uses animal models to isolate and mechanistically evaluate genetic susceptibility to human disease. Rat strains have different susceptibility phenotypes to chemical-induced carcinogenesis. Selective breeding and genetic linkage analysis using a 7,12-dimethylbenz(a)anthracene (DMBA) rat mammary carcinogenesis model have identified Mammary carcinoma susceptibilityquantitative trait loci …

Defects In Fetal Mouth Movement And Pharyngeal Patterning Underlie Cleft Palate Caused By Retinoid Deficiency., Regina Friedl

Electronic Theses and Dissertations

Cleft palate is a common birth defect. Etiologic mechanisms of palate cleft include defects in palate morphogenesis, mandibular growth, or spontaneous fetal mouth movement. Cleft palate linked to deficient fetal mouth movement has been demonstrated directly only in a single experimental model of loss of neurotransmission. Here, using retinoid deficient mouse embryos, we demonstrate directly for the first time that deficient fetal mouth movement and cleft palate occurs as a result of mis-patterned development of pharyngeal peripheral nerves and cartilages. Retinoid deficient embryos were generated by inactivation of retinol dehydrogenase 10 (Rdh10), which is critical for production of …

Development Of A Functional In Vitro 3d Model Of The Peripheral Nerve, Wesley Anderson

Electronic Theses and Dissertations

Peripheral neuropathies, affect approximately 20 million people in the United States and are often a complication of conditions such as diabetes that can result in amputation of affected areas such as the feet and toes. In vitro methodologies to facilitate the understanding and treatment of these disorders often lack the cellular and functional complexity required to accurately model peripheral neuropathies. In particular, they are often 2-D and functional readouts, such as electrical activity, are limited to cell bodies thereby limiting the understanding of axonopathy which often characterizes these disorders. We have developed a functional 3-D model of peripheral nerves using …

Endothelial Hspa12b Is A Novel Protein For The Preservation Of Cardiovascular Function In Polymicrobial Sepsis Via Exosome Mir-126, Xia Zhang

Electronic Theses and Dissertations

Sepsis is the most frequent cause of mortality in most intensive care units. Cardiovascular dysfunction is a major complication associated with sepsis, with high mortality rates up to 70%. Currently, there is no effective treatment approach for sepsis.

The integrity of the endothelium is fundamental for the homeostasis of the cardiovascular system. Sepsis induces endothelial cell injury which is the key factor for multiple organ failure. The increased expression of adhesion molecules and chemokines in endothelial cell promotes leukocytes infiltration into the tissue. The loss of tight junction proteins and increased permeability of the endothelial cells will provoke tissue hypoxia …

Exploring The Unique Characteristics Of Cancer In Adolescents And Young Adults In Tennessee, Megan Quinn

Electronic Theses and Dissertations

Adolescents and Young Adults (AYAs) ages 15-39 years with cancer have received little attention in the medical and health fields, resulting in a lack of progress for this age group. Little is known about the unique biologic, epidemiologic, and psychosocial issues that play an integral role in the AYA cancer journey. The purposes of this study were to use the Tennessee Cancer Registry for all new cancer cases from 2004-2008 to determine 1) the main types of cancer that affect AYAs in TN, 2) the predictors of late-stage diagnosis of melanoma, and 3) the factors that predict a total thyroidectomy …

Using Modeling And Simulation To Evaluate Disease Control Measures, Tracy Atkins

Electronic Theses and Dissertations

This dissertation introduced several issues concerning the analysis of diseases by showing how modeling and simulation could be used to assist in creating health policy by estimating the effects of such policies. The first question posed was how would education, vaccination and a combination of these two programs effect the possible outbreak of meningitis on a college campus. After creating a model representative of the transmission dynamics of meningitis and establishing parameter values characteristic of the University of Central Florida main campus, the results of a deterministic model were presented in several forms. The result of this model was the …