Life Sciences Commons^™

Investigating The Relationship Between Metabolic Reprogramming And Peripheral Cd4+ T-Cell Inflammation In Human Type 2 Diabetes Pathogenesis, Gabriella Kalantar

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

Chronic, low-grade systemic inflammation rises in obesity and promotes type 2 diabetes (T2D). Circulating immune cells are key indicators of obesity and T2D pathogenesis. T cells outnumber monocytes, in blood, suggesting that T cells might fuel peripheral inflammation in obesity/T2D. Our lab’s work supports this idea by identification of a Th17 cytokine profile in T2D from T-cell stimulated peripheral blood mononuclear cells. Work described herein further supported this work by demonstrating that T cells dominate peripheral inflammation over monocytes across the spectrum of obesity and glycemic control. Our lab has also recently shown that inflammation changes during prediabetes (preT2D), identified …

Dissecting The Role Of Actin-Myosin Motor And Calcium – Based Organelle Secretion In Motility Of Sarcocystis Neurona, Parul Suri

Theses and Dissertations--Veterinary Science

Sarcocystis neurona is a protozoan parasite that causes a rare neurological disorder in horses called Equine Protozoal Myeloencephalitis (EPM). Apicomplexa use actin-myosin based motor and organelle secretion to interact with the host cell and invade it. Despite the importance of motility and invasion-needed factors, the mechanisms by which S. neurona employs host cell association strategies to interact remains largely undefined. To address this knowledge gap, we hypothesize that just like other Apicomplexa, S. neurona utilizes actin polymerization for substrate-dependent gliding. Moreover, we also hypothesize that micronemes of S. neurona secrete proteins that are calcium-dependent. Based on previous studies in T. …

The Microbiome Of The Equine Roundworm, Parascaris Spp., Jennifer Lynn Cain

Theses and Dissertations--Veterinary Science

Parasitic nematodes, including the large roundworms colloquially known as ascarids, affect the health and well-being of livestock animals worldwide. The equine ascarid, Parascaris spp., was the first ascarid parasite to develop wide-spread anthelmintic drug resistance, with other species slowly following suit. There are no new classes of anthelmintics currently in development, and a solution to the ever-increasing prevalence of resistance is desperately needed. The microbiome has been shown to be an important factor in the fitness and health of many organisms and changes to microbiome composition have been associated with a plethora of diseases. The microbiome is also important to …

Antibiotic Permeation In Gram-Negative Bacteria And Contribution Of Inflammasome Activation And Pyroptosis In Pathogenesis Of Salmonella Systemic Infection, Ankit Pandeya

Theses and Dissertations--Chemistry

Antibiotic resistance is one of the major global issues in the field of public health and medicine. Good antibiotic candidates need to be selectively toxic, inhibit cellular target, and effectively penetrate and accumulate in bacterial cells. The last factor is a formidable barrier in the development of antimicrobials effective in Gram-negative bacteria, due to the presence of two layers of cell envelope. The first half of my thesis focuses on understanding the permeation of small molecules through this formidable cell envelope, distribution inside the cell of Gram-negative bacteria, and design of novel methods to make small molecules effectively cross the …

Cell-Engineered Vesicles For Therapeutic Delivery And Immunomodulatory Applications, Khaga Neupane

Theses and Dissertations--Chemistry

Development of a new kind of drug delivery system (DDS) that could efficiently deliver therapeutics to the cell of interest would allow us to accomplish cell-specific drug delivery while eliminating systemic toxicity. Although nanocarriers including endogenously released extracellular vesicles (EEVs), liposomes, and small molecules seem to be promising drug delivery systems, biological challenges persist for their use in clinical applications. Here, we demonstrate nanovesicles engineered by fragmenting cellular membranes can be exploited as versatile DDSs for therapeutics delivery as well as immunomodulatory functions. Cell-engineered vesicles were produced by cavitating cells using nitrogen gas at high pressure followed by serial centrifugation. …

Myelin, Cpla2, And Azithromycin: Modulation Of Macrophage Activation In Spinal Cord Injury Inflammation, Timothy J. Kopper

Theses and Dissertations--Physiology

Spinal cord injury (SCI) produces a chronic inflammatory state primarily mediated by macrophages consisting of resident microglia and infiltrating monocytes. These chronically activated SCI macrophages adopt a pro-inflammatory, pathological state that continues to cause additional damage after the initial injury and inhibits recovery. While the roles of macrophages in SCI pathophysiology are well documented, the factors contributing to this maladaptive response are poorly understood. Here, we identify the detrimental effects of myelin debris on macrophage physiology and demonstrate a novel, activation state-dependent role for cytosolic phospholipase-A2 (cPLA₂) in myelin- mediated potentiation of pro-inflammatory macrophage activation. Macrophage- mediated inflammatory …

Muscle Mass And Immune Function In The Senior Horse, Alisa Christina Herbst

Theses and Dissertations--Veterinary Science

Senior horses (≥ 15 years) represent up to one-third of the global equine population, and the proportion of old horses (≥ 20 years) in the U.S. has been steadily increasing. Aging is associated with a loss of skeletal muscle mass in horses, and while age-related muscle loss is comparingly well characterized in humans, little is currently known concerning underlying mechanisms, adverse outcomes, or the prevalence of low muscle mass in senior horses. One factor proposed to play a role in the development of age-related muscle atrophy in humans is inflamm-aging, a low-grade inflammation that affects elderly people and that has …

Human Regulatory T Cells Control Inflammation From Effector T Cells In Prediabetes, Rui Liu

Theses and Dissertations--Pharmacy

Type 2 diabetes (T2D) is a chronic low-grade inflammatory disease. A T cell cytokine profile (Th17) from PBMCs can distinguish obese T2D from obese non-diabetes subjects. Individual T cell subsets interact with each other and the diverse subsets jointly determine overall inflammation. Cellular metabolism drives cytokine production of CD4⁺ T cells, and therefore contributes to inflammation in T2D. However, specific changes in metabolism and function of CD4⁺ T cells during the progression from lean healthy to obese and diabetic stages in people have not been clarified.

We hypothesize that human regulatory T cells (Treg) impact metabolism of effector …

Monocyte Abundance And White Blood Cell Expression Of Prolactin And Nf-Kb Pathway Genes In Beef Steers Are Altered By Grazing Toxic Endophyte-Infected Tall Fescue And Lipopolysaccharide Challenge, Cecilia Winfrey

Theses and Dissertations--Animal and Food Sciences

Experiment 1 tested the hypothesis that ad libitum consumption of a 1:1 blend (MIX) of sodium selenite (ISe) and SELPLEX vs solely ISe as selenium (Se) supplements (27 ppm) in a vitamin-mineral mix (V-M) by steers subjected to summer-long grazing of toxic endophyte-infected tall fescue (TE) would ameliorate the negative effects of TE by positively affecting the expression pattern of prolactin (PRL) and NF-kB pathway genes by circulating leukocytes (WBC). Experiment 2 tested the hypothesis that the MIX form of supplemental Se also would ameliorate the negative effects of in vitro blood lipopolysaccharide challenge (LPS) on WBC gene expression. The …

Mast Cells As Novel Effector Cells In The Pathogenesis Of Chronic Graft-Versus-Host Disease, Ethan Strattan

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

Hematopoietic stem cell transplantation (HSCT) is most commonly a treatment for inborn defects of hematopoiesis or acute leukemias. Widespread use of HSCT, a potentially curative therapy, is hampered by onset of graft-versus-host-disease (GVHD), a condition wherein the donor cells recognize the patient tissues as non-self. GVHD can manifest anywhere from weeks to decades post-transplant and is classified as either acute or chronic GVHD, both of which are significant causes of transplant-related morbidity and mortality.

However, GVHD is a complex, multifactorial, and enigmatic disease. The factors driving GVHD at the cellular and molecular level are incompletely understood. Immunosuppression targeting T-cells has …

Relationships Between Animal Temperament And Systemic Immune Responses In Beef Cattle Exposed To Conditions Associated With Conventional Management, Alexander W. Altman

Theses and Dissertations--Animal and Food Sciences

Measures of temperament have been shown to influence physiological responses. Exit velocity (EV) has been identified as an objective, robust measure of temperament that can be used to predict subsequent performance of cattle. Additionally, previous studies from our lab indicate this measure of temperament may be related to production of interferon-γ (IFN-γ), a cytokine associated with cell-mediated immunity (CMI). Whereas research has investigated effects of EV upon immune responses, the overall goal of these studies was to examine this relationship under a variety of scenarios including human handling, transportation, and exposure to endophyte-infected tall fescue (E+) for determination of its …

Host Restriction Factors In The Replication Of Tombusviruses: From Rna Helicases To Nucleocytoplasmic Shuttling, Cheng-Yu Wu

Theses and Dissertations--Plant Pathology

Positive-stranded (+)RNA viruses replicate inside cells and depend on many cellular factors to complete their infection cycle. In the meanwhile, (+)RNA viruses face the host innate immunity, such as cell-intrinsic restriction factors that could block virus replication.

Firstly, I have established that the plant DDX17-like RH30 DEAD-box helicase conducts strong inhibitory function on tombusvirus replication when expressed in plants and yeast surrogate host. This study demonstrates that RH30 blocks the assembly of viral replicase complex, the activation of RNA-dependent RNA polymerase function of p92pol and viral RNA template recruitment.

In addition, the features rendering the abundant plant DEAD-box helicases either …

Pyocyanin, A Virulence Factor Produced By Sepsis-Causing Pseudomonas Aeruginosa, Promotes Adipose Wasting And Cachexia, Nika Larian

Theses and Dissertations--Pharmacology and Nutritional Sciences

Sepsis is a leading cause of death among critically ill patients that results in metabolic alterations including hypercatabolism, lipoatrophy, and muscle wasting, contributing to the development of cachexia. Septic cachexia is associated with loss of body weight, fat mass, and lean mass and dysregulated immune function. There are currently no efficacious treatment strategies for septic cachexia, and nutritional interventions have limited success in preventing hypercatabolic wasting. Pyocyanin is a virulence factor produced by sepsis-causing Pseudomonas aeruginosa that has been shown to activate the aryl hydrocarbon receptor (AhR), increase inflammation, and produce reactive oxygen species. Thus, pyocyanin represents a novel mechanistic …

Effects Of Endophyte-Infected Tall Fescue Seed And Bromocriptine On Endocrine And Immune Function In Horses, Jessica Marie Hanneman

Theses and Dissertations--Veterinary Science

Consumption of endophyte-infected (E+) grasses has long been associated with health problems in animals. In cattle E+ tall fescue consumption leads to fescue toxicosis, and in horses it leads reproductive problems. The health-related issues associated with endophyte consumption have been attributed to the effects caused by the ergot alkaloids produced by the fungus. These ergot alkaloids are considered D2-like receptor agonists, and 5-HT2 serotonin and α-adrenergic receptor partial agonists. Many studies in humans, swine, cattle, and horses have identified that ergopeptines cause a decrease in prolactin production due to their dopaminergic activities. Additionally, these molecules have been found to cause …

Alternatively Activated Macrophages In Pseudomonas Aeruginosa Pneumonia: Modulation Of The Nf-Κb Signaling Pathway And The Immunomodulatory Role Of Arginase-1, Dalia Haydar

Theses and Dissertations--Pharmacy

Background: Azithromycin polarizes macrophages into an alternative phenotype and promotes a regulated immunity. Arginase is an important effector of these macrophages believed to play an essential role in decreasing injury and promoting repair.

Hypothesis: Decreases in inflammation in response to Pseudomonas aeruginosa (PA) pneumonia achieved by polarizing macrophages to an alternative phenotype is dependent upon the production of arginase.

Methods: Requirement of arginase was examined by pharmacological inhibition using S-(2-boronoethyl)- l-cysteine (BEC) or l-norvaline and by infecting arginase-1 conditional knock-out mice (Arg1^flox/flox;Lyz2-cre (Arg1^Δm)) with PA intratracheally. Arg1^ΔM and control Arg1^flox/flox mice were then …

Lymphocyte-Mediated Inflamm-Aging In The Horse, Melissa Hope Siard

Theses and Dissertations--Veterinary Science

Senior horses (≥20 years) exhibit inflamm-aging, or chronic, low-grade inflammation that occurs systemically with aging, similarly to humans. Inflamm-aging has previously been characterized in the horse in circulation as well as specifically being mediated by lymphocytes and monocytes. In humans, inflamm-aging has been associated with increased morbidity and mortality. However, in the horse, relatively little about inflamm-aging is known regarding clinical effects or factors influencing severity. The contribution of lymphocytes to inflamm-aging of senior horses was examined, specifically through determining the relationships of inflamm-aging with various other health parameters, effects of seasonality, and the extent to which inflamm-aging can be …

Effects Of Chromium On Mouse Splenic T Lymphocytes And Effects Of Ethanol Exposure During Early Neurodevelopment On Behaviors In Mice, Lu Dai

Theses and Dissertations--Toxicology and Cancer Biology

The dissertation consists of three major projects with the focus on the immunotoxicity of chromium and the behavior disorders caused by early ETOH exposure respectively.

Hexavalent chromium [Cr(VI)] is widely used in various industrial processes and has been recognized as a carcinogen. As the first line of host defense system, the immune system can be a primary target of Cr(VI). T cell population represents a major arm of the immune system that plays a critical role in host anti-tumor immunity. Dysfunction of T cells compromises host anti-tumor immunity resulting in oncogenesis. Using mouse splenic T cells as an in vitro …

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 …

Immune Evasion By Division Of Labor: The Trophic Life Cycle Stage Of Pneumocystis Murina Suppresses Innate Immunity To This Opportunistic, Fungal Pathogen, Heather M. Evans

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

Pneumocystis species are opportunistic fungal pathogens that cause severe pneumonia in immunocompromised hosts, including AIDS patients. Pneumocystis species have a biphasic life cycle consisting of single-nucleated trophic forms and ascus-like cysts. Both stages live within the host, and, thus, must contend with threats from the host immune system. The cyst cell wall β-glucans have been shown to stimulate immune responses in lung epithelial cells, dendritic cells and alveolar macrophages. Little is known about how the trophic life forms, which do not have a fungal cell wall, interact with immune cells. In this study, the immune response to the life cycle …

Novel Role Of Prostate Apoptosis Response-4 Tumor Suppressor In B-Cell Chronic Lymphocytic Leukemia, Mary Kathryn Mckenna

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

Chronic Lymphocytic Leukemia (CLL) is defined by the accumulation of clonally expanded CD5+ and CD19+ B lymphocytes in blood and secondary lymphoid organs with impaired apoptotic mechanisms. CLL represents one third of all leukemia cases with an average age of 72 years at diagnosis making it the most common adult leukemia. The Eµ-Tcl1 mouse serves as an excellent model to study the development of CLL as they progress to a CLL like disease by 9-14 months of age, due to overexpression of an oncogene, T cell Leukemia 1(Tcl1), specifically in B cells through the Ig VH promoter and Eµ enhancer …

Elucidating Binding, Fusion And Entry Of Human Metapneumovirus, Edita M. Klimyte

Theses and Dissertations--Molecular and Cellular Biochemistry

Human metapneumovirus (HMPV) is a respiratory pathogen in the Paramyxoviridae family that infects nearly 100% of the world population. This enveloped RNA virus causes severe viral respiratory disease in infants, the elderly, and immunocompromised patients worldwide. Despite its prevalence and importance to human health, no therapies are available against this pathogen. Entry of paramyxoviruses into host cells generally requires the coordinated activity of the attachment glycoprotein, G, which interacts with a cell receptor, and the fusion glycoprotein, F, which promotes subsequent fusion of viral and cellular membranes. However, HMPV F is the primary viral protein mediating both binding and fusion …

The Role Of Batf2 In Lps/Ifnγ Polarized Macrophages, Marie A. Gehman

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

Transcription factors regulate distinct macrophage functions by regulating gene expression in response to micro-environmental cues. This functional plasticity is critical for regulating innate and adaptive immune responses during infection and during chronic disease processes including inflammatory diseases and cancer. Microarray analysis of macrophages polarized to a pro-inflammatory (M1) phenotype with LPS and IFNγ revealed that basic leucine zipper transcription factor ATF-like 2 (Batf2), a member of the AP1 transcription factors, is selectively upregulated in M1 macrophages compared to anti-inflammatory IL-4-polarized (M2) macrophages. The initial hypothesis was that Batf2 is a master regulator of gene expression that orchestrates M1 polarization. To …

Role Of Scavenger Receptor Class B Type I In Thymopoiesis, Zhong Zheng

Theses and Dissertations--Nutritional Sciences

T cells, which constitute an essential arm in the adaptive immunity, complete their development in the thymus through a process called thymopoiesis. However, thymic involution can be induced by a couple of factors, which impairs T cell functions and is slow to recover. Therefore, understanding how thymopoiesis is regulated may lead effort to accelerate thymic recovery and improve immune functions in thymocyte-depleted patients. In this project, we identified scavenger receptor BI (SR-BI), a high density lipoprotein (HDL) receptor, as a novel modulator in thymopoiesis. In mice, absence of SR-BI causes a significant reduction in thymus size after puberty and a …

Role Of Viral And Host Factors In Influenza Virus Mediated Inhibition Of Interleukin-23, Ashish Tiwari

Theses and Dissertations--Veterinary Science

Influenza virus is one of the major respiratory pathogens of humans as well as animals, including equines. There is an increasing evidence that bacterial infections are the most common cause of the death during influenza. In horses also, secondary bacterial pneumonia can lead to death, and surviving horses may take up to six months for the complete recovery resulting in heavy economic loss to the equine industry. Interleukin (IL)-23 mediated innate immune response has been shown to protect the host from various respiratory bacterial infections. However, studies to investigate the role of host and viral factors in the regulation of …

Modulation Of Vaccine-Induced Responses By Anthelmintic Treatment In Ponies, Emily Rubinson

Theses and Dissertations--Medical Sciences

Vaccines and anthelmintics induce an inflammatory response in equids. Since they are commonly given concurrently, it is practical to study any interaction between them. This study evaluated whether IVM and PYR would modulate the acute phase inflammatory response, the systemic gene expression of pro-inflammatory cytokines, and vaccine-specific titers induced by WNV, EHV, and KLH vaccines. Naturally-infected, yearling ponies were sorted by gender, then fecal epgs. They were randomly assigned to three treatment groups: IVM, PYR, and control. All ponies received vaccinations intramuscularly on days 0 and 29. Whole blood, serum, and plasma samples were collected 1, 3, and 14 days …

Equine Serum Antibody Responses To Streptococcus Equi And Streptococcus Zooepidemicus, Rafaela De Negri

Theses and Dissertations--Veterinary Science

Streptococcus zooepidemicus (Sz) and Streptococcus equi (Se) share 98% DNA sequence homology, but display different pathogenic properties. Infection by one organism does not cross-protect against the other. To better understand pathogenic differences between these organisms and gain information about which proteins are expressed in horses infected experimentally with Se, intrauterine Sz or naturally with respiratory Sz we compared antibody specificities of convalescent sera using ELISA. These comparisons were based on sets of 8 and 14 immunoreactive recombinant proteins of Se strain CF32 and Sz strain NC78, respectively. Sera from donkeys that were previously naturally affected with strangles and later developed …

Detection Of Antibodies Against Parascaris Equorum Excretory-Secretory Antigens, Steffanie V. Burk

Theses and Dissertations--Animal and Food Sciences

Parascaris equorum is a nematode parasite that infects young horses, sometimes causing unthriftiness, respiratory signs, or intestinal impaction in severe cases. Infection can be diagnosed by detection of eggs in feces, but this is only possible after the worms are fully mature. The goal of this study was to develop an antibody-based test for prepatent diagnosis of P. equorum infection. To produce western blot (WB) antigen, P. equorum larvae were cultured for collection of excretory-secretory antigens (ESA). Sera from 18 pregnant broodmares, their subsequent foals, and a group of 12 older mares and geldings were analyzed. In order to check …

Evidence For The Maturation Of Cellular Immune Responses In Equine Infectious Anemia Virus-Infected Ponies, Chong Liu

Theses and Dissertations--Veterinary Science

Equine infectious anemia virus (EIAV) has been used as a model to investigate protective mechanisms against lentiviruses. Unlike other lentiviruses, EIAV replication can be eventually controlled in most infected horses leading to an inapparent carrier state free of overt clinical signs which can last for many years. Maintenance of this carrier state is absolutely dependent on active immune responses as evidenced by the fact that immunosuppressive drugs can induce the recurrence of disease. However, the immune mechanisms that are responsible for this control of infection are not yet identified. As the resolution of the initial infection is correlated with the …

On T Cell Fate Decisions: Retinol, Metabolism And Itreg Differentiation, Gavin I. Ellis

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

The mammalian immune system is equipped to both eliminate pathogenic microorganisms and tumors, while remaining in homeostasis with commensal species at mucosal surfaces and tolerant towards self. Suppressor regulatory T cells (Tregs) are a major sentinel of this immunological tolerance. Induced Tregs (iTregs) arise in the periphery following the integration of cues from the metabolites, cytokines, etc. which make up its milieu. Dysregulation of iTreg development, function or homing underlies the etiology of many autoimmune diseases and immunopathologies. The amelioration or prevention of multiple murine disease models by boosting Treg cell numbers foreshadows clinical efficacy of iTreg therapy, but an …

Rhodococcus Equi Infection And Interferon-Gamma Regulation In Foals, Lingshuang Sun

Theses and Dissertations--Veterinary Science

Rhodococcus equi (R. equi) is one of the most serious causes of pneumonia in young foals. The clinical disease is of great concern to breeding farms worldwide due to the impact of mortality on economic losses. While adult horses are resistant to R. equi, foals exhibit a distinct age-associated susceptibility. The mechanism underlying this susceptibility in foals is not well understood. Interferon-gamma (IFNg) plays an important role in the clearance of R. equi, but its expression is impaired in neonatal foals. Moreover, the regulation of this age-related IFNg expression in foals remains unknown. In humans, IFNg …