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- Myeloid (3)
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- Colon cancer (2)
- Glucan (2)
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- Innate immunity (2)
- Metabolism (2)
- Pancreatic cancer (2)
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- Accessory cells (1)
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- Beta glucan (1)
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- Borrelia burgdorferi (1)
- CD47 (1)
- CF (1)
- CRISPR/Cas9 (1)
- Cancer (1)
- Candida (1)
- Candida albicans (1)
- Cerebral Ischemia/Reperfusion (1)
- Chimerism (1)
- Chlamydia (1)
- Co-infection (1)
- CpG-ODN (1)
- Crohn's disease (1)
Articles 1 - 26 of 26
Full-Text Articles in Medical Sciences
Irreversible Electroporation Potentiates Beta Glucan Induced Trained Innate Immunity: A Novel Combination Treatment For Pancreatic Adenocarcinoma., Matthew Woeste
Electronic Theses and Dissertations
Pancreatic cancer (PC) is a challenging diagnosis yet to benefit from advances in immune oncologic treatments. Irreversible electroporation, a non-thermal method of tumor ablation, is used in treatment of select patients with locally advanced unresectable PC and has potentiated the effect of certain immunotherapies. Yeast-derived particulate β-glucan induces trained innate immunity and successfully reduces murine PC tumor burden. This study tests the hypothesis that IRE may augment β-glucan-induced trained immunity in the treatment of PC. β-Glucan-trained pancreatic myeloid cells were evaluated ex vivo for trained responses and anti-tumor function after exposure to ablated and un-ablated tumor conditioned media. β-Glucan and …
Investigating The Pi3k/Akt/Atm Pathway, Telomeric Dna Damage, T Cell Death, And Crispr/Cas9-Mediated Gene Editing During Acute And Chronic Hiv Infection, Sushant Khanal
Electronic Theses and Dissertations
Human Immunodeficiency Virus (HIV) infection initiates major metabolic and cell- survival complications. Anti-retroviral therapy (ART) is the current approach to suppress active HIV replication to a level of undetected viral load, but it is not a curative approach. Newer and sophisticated gene editing technologies could indeed be a potent antiviral therapy to achieve a clinical sterilization/cure of HIV infection. Chronic HIV patients, even under a successful ART regimen, exhibit a low-grade inflammation, immune senescence, premature aging, telomeric DNA attrition, T cell apoptosis, and cellular homeostasis. In this dissertation, we investigated CD4 T cell homeostasis, degree of T cell apoptosis, an …
The Role Of Obesity In Macrophage-Mediated Mechanisms Promoting Early-Onset Colon Cancer., Katharina Marietta Scheurlen
The Role Of Obesity In Macrophage-Mediated Mechanisms Promoting Early-Onset Colon Cancer., Katharina Marietta Scheurlen
Electronic Theses and Dissertations
Early-onset colon cancer (EOCC) is a leading cause of cancer death among people younger than 50 years of age in the United States and is associated with metabolic dysfunction and obesity. Anti-inflammatory tumor-associated macrophages (TAM) and low Peroxisome Proliferator Activated Receptor Gamma (PPARγ) gene expression in colon cancer (CC) tissue promote tumor progression and decreased patient survival. Obesity-related hormones, such as leptin and adiponectin, have the potential to affect gene expression in TAM to promote CC progression and thereby link obesity and EOCC. The aim of this project was to identify target genes in human CC and to investigate the …
Genital Chlamydia Infection Is Influenced By The Female Sex Hormones Estrogen And Progesterone In Vivo, Amy Gail Gravitte
Genital Chlamydia Infection Is Influenced By The Female Sex Hormones Estrogen And Progesterone In Vivo, Amy Gail Gravitte
Electronic Theses and Dissertations
Chlamydia is the most common bacterial sexually transmitted infection in the United States and worldwide. It often goes unnoticed due to lack of symptoms and left untreated it can ascend the female genital tract to cause sequelae like pelvic inflammatory disease and irreversible tubal infertility. In reproductive-aged women, female sex hormones estrogen (E2) and progesterone (P4) concentrations fluctuate during the menstrual cycle and are influenced by hormonal contraceptives and hormone replacement therapy. E2 and P4 influence genital Chlamydia infection in women and mice, but these multifactorial interactions are not entirely mapped out. The complex interplay of E2 and P4 with …
The Importance Of Noncapped Viral Genomic Rna To Alphaviral Infection And Pathogenesis., Autumn Lapointe
The Importance Of Noncapped Viral Genomic Rna To Alphaviral Infection And Pathogenesis., Autumn Lapointe
Electronic Theses and Dissertations
Alphaviruses are mosquito-borne arboviruses that have a positive sense, single-stranded RNA genome, which are capable of causing severe disease and thus pose a significant burden to public health. During alphaviral replication, significant quantities of viral genomic RNAs that lack the canonical alphaviral 5’ cap structure are produced and packaged into viral particles, despite the fact that these noncapped genomes cannot be translated and are essentially noninfectious. The production and packaging of the noncapped genomes has been found to be true for infections across multiple vertebrate and invertebrate cell lines and alphavirus species, although the proportion of ncgRNA produced differs. Despite …
Harnessing The Power Of Trained Immunity In The Setting Of Pancreatic Cancer: A Novel Mechanism Of Immune Trafficking And Tumor Control., Anne Elena Geller
Harnessing The Power Of Trained Immunity In The Setting Of Pancreatic Cancer: A Novel Mechanism Of Immune Trafficking And Tumor Control., Anne Elena Geller
Electronic Theses and Dissertations
Despite the success of immunotherapy in many types of cancer, pancreatic adenocarcinoma (PDAC) has yet to benefit. Innate immune cells are critical to antitumor immunosurveillance and recent studies have revealed that these populations possess a form of memory, termed trained innate immunity, which occurs through transcriptomic, epigenetic, and metabolic reprograming. Though trained innate immunity has mostly been investigated in the context of infection, the induction of trained innate immunity could also protect against tumors, and specifically pancreatic tumors. Here, we demonstrate that yeast-derived particulate β-glucan, a known inducer of trained immunity, traffics to the pancreas following IP administration. This causes …
Development, Expansion And Role Of Myeloid-Derived Suppressor Cells In Post-Sepsis Immune Suppression, Tuqa Alkhateeb
Development, Expansion And Role Of Myeloid-Derived Suppressor Cells In Post-Sepsis Immune Suppression, Tuqa Alkhateeb
Electronic Theses and Dissertations
Myeloid-derived suppressor cells (MDSCs) numbers increase significantly in sepsis and are associated with high mortality rates. These myeloid cell precursors promote immunosuppression, especially in the late (post sepsis) stage. However, the mechanisms that underlie MDSC expansion and programming are not completely understood. To investigate these mechanisms, we used a cecal-ligation and puncture (CLP) mouse model of polymicrobial sepsis that progresses from an early/acute proinflammatory phase to a late/chronic immunosuppressive phase. Previous studies in our laboratory showed that microRNA (miR)-21 and miR-181b elevate levels of the transcription factor nuclear factor 1 (NFI-A) that promotes MDSC expansion. We report here that miR-21 …
Tumor-Derived Exosomes Drive Immunosuppressive Macrophages In A Pre-Metastatic Niche Through Nf-Kβ Dependent Glycolytic Metabolic Reprogramming., Samantha M. Morrissey
Tumor-Derived Exosomes Drive Immunosuppressive Macrophages In A Pre-Metastatic Niche Through Nf-Kβ Dependent Glycolytic Metabolic Reprogramming., Samantha M. Morrissey
Electronic Theses and Dissertations
The formation of a pre-metastatic niche is a fundamental requirement for primary tumor metastasis. One of the defining characteristics of a pre-metastatic niche is infiltration of immunosuppressive macrophages. However, how these macrophages acquire their immunosuppressive phenotype remains largely unexplored. Here, we demonstrate that tumor-derived exosomes (TDE) polarize macrophages towards an immunosuppressive phenotype characterized by increased PD-L1 expression through NF-kB-dependent metabolic reprogramming in mice and humans. While NF-κB has previously been shown to act as a direct transcription factor for PD-L1, we report a novel mechanism where TDE-induced NF-κB activation drives PD-L1 expression by augmenting the glycolytic capacity of macrophages through …
Plasmodium Impairs Antibacterial Innate Immunity To Systemic Infections In Part Through Hemozoin-Bound Bioactive Molecules., Christopher Lynn Harding
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 …
Transient Display Of Chimeric Proteins On Biological Surfaces As An Effective Strategy For Modulations Of Innate And Adaptive Immune Responses., Pradeep Shrestha
Transient Display Of Chimeric Proteins On Biological Surfaces As An Effective Strategy For Modulations Of Innate And Adaptive Immune Responses., Pradeep Shrestha
Electronic Theses and Dissertations
The major premise of this dissertation was to transiently display novel immunological ligands on biological membranes as a localized means of modulating innate and adaptive immune responses with applications to bone marrow and pancreatic islet transplantation. In Chapter two, we engineered donor allogeneic bone marrow cells to transiently display a novel form of FasL, SA-FasL, to efficiently purge out alloreactive donor T cells to prevent acute GVHD. In Chapter three, we engineered pancreatic islets with a novel form of CD47, SA-CD47, to modulate instant blood mediated inflammatory reaction (IBMIR) to prevent immediate islet graft loss following intraportal transplantation. GVHD is …
A Distinct Pattern Of Sterile Inflammation Induced By Zinc Oxide Nanowires., Ruqaih Salem Alghsham
A Distinct Pattern Of Sterile Inflammation Induced By Zinc Oxide Nanowires., Ruqaih Salem Alghsham
Electronic Theses and Dissertations
In recent years, there has been an increasing interest in nanotechnology. Engineered nanomaterials (ENMs) become an increasingly important area in nanotechnology. Recent developments in ENMs have drawn commercial and research attention in many areas such as agriculture, medicine, and Industry. High-aspect ratio zinc oxide nanowires (ZnONWs) have become one of the most significant ENMs due to their remarkable physical properties which makes them useful in a wide-range of applications. However, questions have been raised about ZnONW safety uses and biological consequences. In this dissertation, we investigated the inflammatory potential of ZnONWs in mouse models. C57BL/6 mice were exposed to ZnONW …
Combination Oral Immunotherapy With Il-10 And Il-12 Effectively Treats Colon Tumors Via Synergistic Effects On Il-17 Producing T Cells And Colon Epithelial Barrier Integrity., Neal Bhutiani
Electronic Theses and Dissertations
In this dissertation, the relationship between colon cancer and inflammation, the utility of novel imaging modalities for diagnosis of colitis and cancer, and the therapeutic efficacy of orally delivered, particle-based immunotherapy for the treatment of colon cancer are evaluated. In Chapters One and Two, multispectral optoacoustic tomography (MSOT) is demonstrated to effectively detect colon inflammation without the use of exogenous contrast prior to detection using conventional colonoscopy. Oral particle uptake is demonstrated in the distal small intestine and proximal colon, confirming site-specific delivery. In Chapter Three, administration of IL-10 and IL-12 containing particles is shown to act synergistically to significantly …
Characterizing The Role Of Fungal Shape In A Zebrafish Model Of Invasive Candidiasis, Brittany Seman
Characterizing The Role Of Fungal Shape In A Zebrafish Model Of Invasive Candidiasis, Brittany Seman
Electronic Theses and Dissertations
Candida albicans is a common hospital-acquired fungal infection, and disseminated disease claims up to one-half of those afflicted. C. albicans has a unique ability to differentiate its shape during infection, and this differentiation is thought to be a major virulence factor during invasive infections. Each shape is proposed to have a specialized role: filaments drive tissue invasion and yeast mediate dissemination to the bloodstream. However, it has been difficult to test these hypotheses for two reasons. First, rigorous testing of shape-specific roles requires diverse strategies of shape modulation that restrict the possibility of manipulation-specific artifacts. Second, although connecting shape to …
Inflammasome Independent Leukotriene-B4 Production Drives Crystalline Silica Induced Sterile Inflammation., Bindu Hegde
Inflammasome Independent Leukotriene-B4 Production Drives Crystalline Silica Induced Sterile Inflammation., Bindu Hegde
Electronic Theses and Dissertations
Silicosis is an irreversible lung inflammatory disease caused by chronic exposure to crystalline silica (CS) and is one of the most prevalent occupational diseases worldwide. Lipid chemoattractant Leukotriene B4 (LTB4) plays an important role in neutrophilic inflammation that drives silicosis and promotes lung cancer. Previous studies in our laboratory have demonstrated that CS-induced neutrophilic inflammation and lung tumor burden in K-rasLA1 mice is abrogated in the LTB4-receptor deficient mice. Another pathway whose importance is well studied in the progression of silicosis is the Nalp3 inflammasome pathway. Studies have shown inflammasome- dependent IL-1b to be …
Revisiting Neutrophil Responses To Toll-Like Receptor 4 : Influence Of Ligand Structures And Cellular Environments., Shuvasree Sengupta
Revisiting Neutrophil Responses To Toll-Like Receptor 4 : Influence Of Ligand Structures And Cellular Environments., Shuvasree Sengupta
Electronic Theses and Dissertations
Neutrophils respond to bacterial LPS through Toll-like receptor 4 (TLR4), which activates or potentiates immune defensive functions and prolongs cell survival. Activation of TLR4 signaling in neutrophils is beneficial for effective clearance of LPS-bearing Gram-negative bacteria, but may also drive aberrant inflammation if not stringently regulated. The regulatory processes by which neutrophil functions are calibrated to respond appropriately to different LPS-bearing bacteria are incompletely understood. Described here are investigations that reveal an unexpected sensitivity of TLR4 in neutrophils to small changes in LPS structure typical of various Gram-negative bacteria, including those that are dangerously virulent (Escherichia coli and Salmonella …
Targeting The Glucose Metabolism Of Myeloid-Derived Suppressor Cells (Mdscs) To Stimulate Cancer Immunity., Jaspreet Grewal
Targeting The Glucose Metabolism Of Myeloid-Derived Suppressor Cells (Mdscs) To Stimulate Cancer Immunity., Jaspreet Grewal
Electronic Theses and Dissertations
Myeloid derived suppressor cells (MDSCs) are a heterogeneous group of immature myeloid cells that are significantly increased in cancer patients and correlate with higher stage and poor prognosis. MDSCs negatively modulate anti-tumor immunity, suppress T cell activity, promote angiogenesis and increase the risk of metastasis. In this study, we report that monocytic-MDSCs (M-MDSCs) but polymorphonuclear-MDSCs (PMN-MDSCs) over-express 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatases 3 (PFKFB3), an important regulator of glycolysis. Furthermore in the melanoma model, M-MDSCs but not PMN-MDSCs suppressed T cell function which correlated with PFKFB3 over-expression and increased rate of glycolysis. PFKFB3 inhibition with the first-in-class small molecule inhibitor, PFK-158 reversed M-MDSC …
Immune Monitoring In Recipients Of Combined Living Donor Kidney And Hematopoietic Stem/Facilitating Cell Transplants., Mark Dewayne Badder
Immune Monitoring In Recipients Of Combined Living Donor Kidney And Hematopoietic Stem/Facilitating Cell Transplants., Mark Dewayne Badder
Electronic Theses and Dissertations
Solid organ transplantation coupled with a hematopoietic stem cell transplant from the organ donor allows for the recipient to cease immunosuppressive therapy after transplant via a chimeric immune system. This beneficial effect of stem cell transplants is negatively affected by graft versus host disease (GVHD). Better understanding of the donor and recipient’s immune system is vital to mitigating graft versus host disease and induction of donor chimerism without GVHD. In this study, flow cytometry was used to characterize immune cells of the recipients’ before and up to eighteen months post transplantation. The recipients were categorized into their respective chimeric groups. …
Toll-Like Receptor 4 Mutation Suppresses Hyperhomocysteinemia-Mediated Hypertension., Anastasia Familtseva
Toll-Like Receptor 4 Mutation Suppresses Hyperhomocysteinemia-Mediated Hypertension., Anastasia Familtseva
Electronic Theses and Dissertations
Background: Hyperhomocysteinemia (HHcy) has been observed to promote hypertension, but the mechanisms are unclear. Toll-like receptor 4 (TLR-4) is a cellular membrane protein that is ubiquitously expressed in all cell types of the vasculature. TLR-4 activation has been shown to promote inflammation that has been associated with pathogenesis of hypertension. In this study, we hypothesize that HHcy induces hypertension by TLR-4 activation that promotes inflammatory cytokine up-regulation (IL-1β, IL-6, TNF-α) and initiation of mitochondrial dysfunction leading to cell death and chronic vascular inflammation. Methods: To test this hypothesis, we used C57BL/6J mice (WT); Cystathionine-β-synthase deficient mice (CBS+/-) with genetic mild …
In Vivo Monitoring Of Therapeutic Efficacy And Virulence Profile By Bioluminescent Klebsiella Pneumoniae., Ramy Ameen Fodah
In Vivo Monitoring Of Therapeutic Efficacy And Virulence Profile By Bioluminescent Klebsiella Pneumoniae., Ramy Ameen Fodah
Electronic Theses and Dissertations
Klebsiella pneumoniae causes an acute respiratory infection in human with severe outcomes and high mortality rates even with antibiotic treatment. Even with its critical clinical importance, few virulence systems have been identified for K. pneumoniae limiting the development of new therapeutic strategies. Accordingly, we performed Next Generation sequencing for the strain ATCC 43816, a virulent strain in mouse respiratory disease models, and compared its genomic data with two previously sequenced strains NTUH-K2044 and MGH 78578 for the purpose of identifying genes required for colonizing host lungs. Furthermore, the virulence potential of the three K. pneumoniae strains were tested in a …
Impact Of Epigallocatechin-3-Gallate (Egcg), A Broad-Spectrum Anti-Inflammatory, In Controlling Intestinal Factors Contributing To Inflammatory Bowel Disease., Gerald Wayne Dryden, Jr.
Impact Of Epigallocatechin-3-Gallate (Egcg), A Broad-Spectrum Anti-Inflammatory, In Controlling Intestinal Factors Contributing To Inflammatory Bowel Disease., Gerald Wayne Dryden, Jr.
Electronic Theses and Dissertations
This dissertation explores the role of epigallocatechin-3-gallate (EGCG), as a potential treatment for patients with inflammatory bowel disease (IBD). IBD is a common disorder that causes a great deal of suffering. Our understanding of the etiologies, pathogenic mechanisms, and treatment targets continues to evolve. Many new therapeutic targets are making their way through the pharmaceutical pipelines. However, not all patients benefit from these therapies. EGCG has long been studied as an anti-cancer agent. Most of our understanding of this compound comes from the oncologic literature. As the pathways of oncology and inflammation converge, new lessons can be taken from the …
Porphyromonas Gingivalis Gingipains Induce A Pro-Inflammatory Extracellular Microenvironment : The Role Of Par-2 And Fibronectin., Jeffrey S. Marschall
Porphyromonas Gingivalis Gingipains Induce A Pro-Inflammatory Extracellular Microenvironment : The Role Of Par-2 And Fibronectin., Jeffrey S. Marschall
Electronic Theses and Dissertations
Periodontitis is a chronic inflammatory disease that is characterized by severe tissue destruction of the gingiva and other tooth supporting structures; if left untreated, tooth loss and disintegration of the alveolar bone occurs. This chronic inflammatory state has been linked to other systemic diseases such as cardiovascular disease, diabetes, rheumatoid arthritis, and Alzheimer’s disease. Porphyromonas gingivalis is the major pathogenic microbe in periodontitis. The main virulence factors of P. gingivalis are the Arg-aa and Lys-aa gingipains, which are proteolytic enzymes implicated in a plethora of activities that allow P. gingivalis to subvert the human immune system in the oral cavity …
Immunomodulation Of Myeloid-Derived Suppressor Cells By Particulate B-Glucan In Cancer., Sabrin Husein Albeituni
Immunomodulation Of Myeloid-Derived Suppressor Cells By Particulate B-Glucan In Cancer., Sabrin Husein Albeituni
Electronic Theses and Dissertations
Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immature myeloid cells that promote tumor progression. In this study, we investigated the effect of dectin-1 stimulation by yeast-derived particulate β-glucan in MDSC function and differentiation in cancer. In vivo treatment of mice bearing lewis lung carcinoma and mammary cell carcinoma with particulate β-glucan decreased tumor weight and splenomegaly, and reduced the accumulation of polymorphonuclear-MDSC (PMN-MDSC) but not monocytic-MDSC (M-MDSC) in the spleen and tumor. In addition, particulate β-glucan differentially modulated the function of different MDSC subsets; it enhanced PMN-MDSC respiratory burst and apoptosis, and induced the differentiation of M-MDSC into …
Novel Therapeutic Approaches For Ischemic Heart And Brain Injury: Modulation Of Toll-Like Receptor-Mediated Signaling Pathways And Pi3k/Akt Signaling, Chen Lu
Electronic Theses and Dissertations
Innate immune and inflammatory responses contribute to myocardial and cerebral ischemia/reperfusion (I/R) injury. Toll-like receptors (TLRs) play a critical role in the induction of innate immune and inflammatory responses via activation of nuclear factor kappa B (NF-κB). We have shown that activation of NF-κB contributes to myocardial and cerebral I/R injury. Indeed, inhibition of TLR4-mediated NF-κB activation significantly decreased myocardial and cerebral I/R injury via activation of PI3K/Akt signaling. PI3K/Akt signaling is an important pathway in regulating cellular survival and inflammatory responses. Therefore, an important question is how to differentially modulate PI3K/Akt signaling and TLR/NF-κB-mediated signaling pathway during I/R injury? …
The Involvement Of Beta-Catenin In The Inflammatory Response Leading To Autoimmune Diabetes Development., Arin Lee Zirnheld
The Involvement Of Beta-Catenin In The Inflammatory Response Leading To Autoimmune Diabetes Development., Arin Lee Zirnheld
Electronic Theses and Dissertations
We identified and characterized a novel defect in β-catenin expression in bone marrow derived dendritic cells (BMDC) from NOD mice, a model for human Type I diabetes. This protein is expressed at high levels throughout the lifespan of the mouse and correlates with increased pro-inflammatory cytokine production by the BMDC and IFNγ induction by T cells cocultured with the BMDC. These defects, including a similar pattern of pro-inflammatory cytokine production, are also observed in human monocytederived DC from diabetic patients. After exploring several potential mechanisms involved in the accumulation of β-catenin in NOD BMDC, we found that β-catenin is phosphorylated …
Dectin-1 Expression Is Altered By Fungal Infection, Polymicrobial Sepsis, And Glucan Administration., Tammy Regena Ozment-Skelton
Dectin-1 Expression Is Altered By Fungal Infection, Polymicrobial Sepsis, And Glucan Administration., Tammy Regena Ozment-Skelton
Electronic Theses and Dissertations
Glucans are fungal cell wall PAMPs that promote survival in polymicrobial and candidal sepsis. Dectin-1 is the primary PRR for glucans. The goals of the present study were to characterize 1) the effects of fungal infection on Dectin-1; 2) the effects of polymicrobial sepsis in the presence and absence of glucan on Dectin-1; 3) the effects of systemic administration of glucans on Dectin-1; and 4) the intracellular trafficking of glucans. Mice were either systemically infected with Candida albicans, or made septic by CLP with and without glucan phosphate (GP) injection, or injected with GP. Flow cytometry was performed to …
Characterization Of Seca-Sod Operon In Borrellia Burgdorferi., Tonya Lynn Nichols
Characterization Of Seca-Sod Operon In Borrellia Burgdorferi., Tonya Lynn Nichols
Electronic Theses and Dissertations
Borrelia burgdorferi, the causative agent of Lyme disease, has been characterized as a microaerophilic spirochete. O2 consumption and utilization potentially yield reactive oxygen intermediates, such as superoxide, hydroxyl radicals, and hydrogen peroxide. This study investigated the expression of the sod gene, which encodes the only, identified oxidative defense mechanism in B. burgdorferi. Using primer extension analysis and RT-PCR, it was found that sod and secA are organized as a single transcriptional unit under the control of σ70-like promoter upstream of the secA open reading frame. Generally, gene expression decreases with increased distance from the promoter; however, secA expression was observed …