Microbiology Commons^™

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 …

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 …

Tumor Necrosis Factor Alpha-Induced Recruitment Of Inflammatory Mononuclear Cells Leads To Inflammation And Altered Brain Development In Murine Cytomegalovirus-Infected Newborn Mice, Maria C. Seleme, Kate Kosmac, Stipan Jonjic, William J. Britt

Physical Therapy Faculty Publications

Congenital human cytomegalovirus (HCMV) infection is a significant cause of abnormal neurodevelopment and long-term neurological sequelae in infants and children. Resident cell populations of the developing brain have been suggested to be more susceptible to virus-induced cytopathology, a pathway thought to contribute to the clinical outcomes following intrauterine HCMV infection. However, recent findings in a newborn mouse model of the infection in the developing brain have indicated that elevated levels of proinflammatory mediators leading to mononuclear cell activation and recruitment could underlie the abnormal neurodevelopment. In this study, we demonstrate that treatment with tumor necrosis factor alpha (TNF-α)-neutralizing …

A Review Of The Role Of Interleukin-6 On Disease Progression In Epithelial Ovarian Cancer, Urmimala Chaudhuri

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Ovarian cancer is one of the most harmful gynecological cancers and has one of the highest mortality rates. As ovarian cancer progresses, the patient has changes to the immune system and energy metabolism with symptoms being weight loss, nausea, and fatigue. Changes to the immune system include overexpression of proinflammatory cytokines. One such cytokine is Interleukin-6 (IL-6), which is a useful prognostic marker to measure disease progression. IL-6 is thought to promote cancer cell proliferation by upregulating apoptosis inhibitory proteins. IL-6 also plays a role in ascites formation. While tumors may initially respond to chemotherapy treatment, most patients will have …

Pulmonary Surfactant Fortified With Cath-2 As A Novel Therapy For Bacterial Pneumonia, Brandon J. Baer

Western Research Forum

Background: Bacterial pneumonia is a leading cause of death worldwide, with high mortality rates persisting even after antibiotic treatment. Current treatments for pneumonia involve administration of antibiotics, however after the bacteria are killed they release toxic substances that induce inflammation and lung dysfunction. Host defense peptides represent a potential solution to this problem through their ability to down regulate inflammation. However, effective delivery to the lung is difficult because of the complex branching structure of the airways. My study addresses this delivery problem by using exogenous surfactant, a pulmonary delivery vehicle capable of improving spreading of these peptides throughout the …

A Blueprint To Evaluate One Health, Simon R. Rüegg, Barry J. Mcmahon, Barbara Häsler, Roberto Esposito, Helen O'Shea, Et Al

Department of Biological Sciences Publications

One Health (OH) positions health professionals as agents for change and provides a platform to manage determinants of health that are often not comprehensively captured in medicine or public health alone. However, due to the organization of societies and disciplines, and the sectoral allocation of resources, the development of transdisciplinary approaches requires effort and perseverance. Therefore, there is a need to provide evidence on the added value of OH for governments, researchers, funding bodies, and stakeholders. This paper outlines a conceptual framework of what OH approaches can encompass and the added values they can provide. The framework was developed during …

The Effect Of Gram-Positive Staphylococcus Aureus Cell Wall Components Lipoteichoic Acid And Peptidoglycan On Cytokine Production, Cytoskeletal Arrangement, And Cell Viability On Raw 264.7 Murine Macrophages, Gabrielle String

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In this study, gram positive Staphylococcus aureus cell wall components such as lipoteichoic acid (LTA) and peptidoglycan (PGN) were used to study the potential inflammatory and anti-inflammatory cytokine response, cytoskeletal arrangement and cell viability on RAW264.7 murine macrophages over 24 hours. The effect of S.aureus LTA and PGN (5 µg/mL) on RAW 264.7 macrophages was evaluated every six hours for twenty-four hours. Inflammatory cytokine (TNF-a) production peaked at 6 hours before decreasing over time. Anti-inflammatory cytokine (IL-10) production peaked between 12 and 18 hours. During the first twenty-four hours, cytotoxicity of treated macrophages, as defined as the release of lactate …

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

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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 …

Cytokine Expression, Cytoskeleton Organization, And Viability Of Sim-A9 Microglia Exposed To Staphylococcus Aureus-Derived Lipoteichoic Acid And Peptidoglycan, Erin Roberts

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In these experiments, SIM-A9 microglia were exposed to Staphylococcus aureus cell wall components lipoteichoic acid (LTA) and peptidoglycan (PGN) at a concentration of 5 ug/mL for six, twelve, eighteen, and twenty-four hours and the cytokine expression, cytoskeleton organization, and cell viability of the cells were observed. Following LTA and PGN exposure, TNF-a; secretion increased at each time interval and was highest observed at 24 hours. No significant IL-10 secretion was detected. Over the 24 hour period, cell viability and cytotoxicity of LTA and PGN treatment groups were not significantly different from the control, indicating the observed inflammatory cytokine response was …

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

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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

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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 …

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

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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'R 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 …

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 …

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 …

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. …

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 …

Characterization Of A Putative Hemolysin Expressed By Sneathia Amnii, A Preterm Birth-Associated Pathogen, Lizette Carrasco, Kimberly Jefferson

Undergraduate Research Posters

The gram-negative bacteria Sneathia amnii is a poorly-characterized commensal of the female urogenital tract frequently associated with adverse clinical outcomes such as bacterial vaginosis (BV), amnionitis, and preterm labor. To investigate its potential role in virulence, we sought to identify and characterize virulence determinants produced by S. amnii in an effort to better understand the pathogenesis of infectious preterm birth. Through sequencing of the Sn35 genome (type strain of S. amnii), we identified two genes with amino acid sequence similarity and structural similarity to the filamentous hemagglutinin (FHA) protein of Bordetella pertussis and its Type Vb transporter. Because S. amnii …

Effects Of Myrrh On Hsv-1 Using Plaque Assay, Badrieah Mohammad Alamri

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Herpes simplex virus type 1 (HSV-1) is a highly infective human pathogen which infects a wide range of population in North America and worldwide. HSV-1 infection has two phases, lytic and latent. Recurrence of HSV-1 is a major challenge to clinicians to control the infection especially in immune depleted individuals. Acyclovir (ACV) is an antiviral drug used to treat HSV-1 infection. Low solubility of ACV in water, mutation of viral thymidine kinase, and mutation of viral DNA polymerase are major problems that cause usage limitations of ACV. Myrrh has been used as an analgesic and anti-inflammatory natural product in middle …

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 …

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 …

Dnp63a Suppresses Cell Invasion By Targeting Rac1 Through Mir-320a, Amjad Ahmed Aljagthmi

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DNp63a, a member of the p53 family of transcription factors, is overexpressed in a number of cancers and known to play a role in proliferation, differentiation, migration and invasion. DNp63a has been shown to regulate several microRNAs that play a role in both development and cancer, but to date there has not been a global analysis of p63- regulated miRNA. Using next-generation sequencing of small RNA from wild type and sip63 transfected HaCaT cells, our laboratory recently identified a number of DNp63a- regulated miRNAs by RNA-Seq studies which may serve as biomarkers of cancer progression. We identified a novel miRNA, …

Biomarkers Of Sepsis: A Retrospective Approach, Jose M. Roberts

Williams Honors College, Honors Research Projects

Background: Biomarkers are taking the spotlight in becoming the norm for early diagnoses. Sepsis is an inflammatory disease that increases metabolic rate in children. The first biomarker is hyponatremia. Hyponatremia is a frequent electrolyte imbalance in clinical practice, often observed in children with inflammatory disease and infection. Presence of hyponatremia is associated with electrical signaling imbalances, inflammation and renal dysfunction. The clinical value of hyponatremia in pediatric patients is unknown. The C-reactive protein is a second biomarker. Its presence signifies that necrotic cells and inflammation are present.

Objectives: To evaluate the use of biomarkers in children seen in the Emergency …

Molecular Biology Of A Surface-Exposed Protein Family Of Bartonella Bacilliformis, Hannah Fay

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Bartonella bacilliformis is a gram negative alpha-proteobacterium native to the Andes of South America. Bartonella causes Carrion’s disease, a potentially life threatening disease transmitted by the sand fly. It has a mortality rate of 88% when untreated and 10% when treated. Diagnostics and control measures for the disease are underdeveloped and no vaccine is available. Recent outbreaks indicate that the range of the pathogen is increasing with nearly 1.7 million people in western South America at risk. Little is known about the epidemiology and pathogenesis of B. bacilliformis. Recent research done by UC San Diego found a paralogous gene …

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-ß (Aß42) 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 Aß42. This culture system, when seeded with Aß42, serves as an in vitro model for Alzheimer’s disease (AD). In a neuronal-microglia co-culture, Aß42 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 …

The Effect Of Gram-Positive Staphylococcus Aureus Cell Wall Components Lipoteichoic Acid And Peptidoglycan On Cytokine Production, Cytoskeletal Arrangement, And Cell Viability On Raw 264.7 Murine Macrophages, Gabrielle String

Browse all Theses and Dissertations

In this study, gram positive Staphylococcus aureus cell wall components such as lipoteichoic acid (LTA) and peptidoglycan (PGN) were used to study the potential inflammatory and anti-inflammatory cytokine response, cytoskeletal arrangement and cell viability on RAW264.7 murine macrophages over 24 hours. The effect of S.aureus LTA and PGN (5 [mu]g/mL) on RAW 264.7 macrophages was evaluated every six hours for twenty-four hours. Inflammatory cytokine (TNF-a) production peaked at 6 hours before decreasing over time. Anti-inflammatory cytokine (IL-10) production peaked between 12 and 18 hours. During the first twenty-four hours, cytotoxicity of treated macrophages, as defined as the release of lactate …

The Impact Of Socs1 And Socs3 Peptide Mimetics On Rho And Cdc42 Proteins Expression, F-Actin Cytoskeleton Rearrangements, And Cytokines Production Of Uninfected And Hsv-1 Infected M1 And M2 Raw 264.7 Murine Macrophages, Maha A. Elwardany

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The immune system plays an essential role in the pathogenesis of HSV-1 during the lytic phase of the disease, orchestrating the inflammatory response, retaining the virus in its latent phase and preventing the recurrence of HSV-1 infection. Macrophages display a vital role in the innate and adaptive immune responses during multiple phases of HSV-1 infection. Polarized macrophages are categorized into two distinct classes with diverse functions. The classically activated M1 can engulf and destroy the microbial agents, produce proinflammatory cytokines, and participate in the pathogenesis of many inflammatory diseases. The alternatively activated M2 induces anti-inflammatory mediators and stimulates tissue remodeling …

Effect Of Exposure Of Raw264.7 Macrophages To Salmonella Typhimurium Components On Cell Viability, Cytoskeleton Re-Arrangement And Cytokine Secretion, Khalid Abdullah Alyahya

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Innate immune system plays an important role in individual's protection against pathogens and in activation of adaptive immune system. Utilizing RAW 264.7 murine macrophages as an innate immune response representative in this study, we analyzed the effect of invasive pathogen's components (e.g. flagellin) on the arrangement of macrophage's cytoskeleton, on viability of immune cells and on secretion of pro-inflammatory and anti-inflammatory cytokines and on fluorescence intensity of cytoskeleton after rearrangement. Additionally, we studied the similarity and differences between bacterial (Salmonella typhimurium) and synthetic TLR4 agonist (synthetic lipid-A) on viability, fluorescence intensity, cytokine secretion, and cytoskeleton rearrangements. Similarly, we studied the …

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

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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 …

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, …

Association Of Gut Luminal Metabolites And Allergic Responses, Ghaith Mohammed Fallata

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Allergy is a global health problem, affecting more than 40% of the world population. Allergy is often associated with a dysregulation of the immune system that becomes overactive against allergens. Several genes are known to be important for the proper homeostasis of the immune system in the epithelial tissues, and the loss of function of genes such as IKKß or SOX9 impacts the interaction between external stimuli and the host. Many of the allergic responses are triggered through the regulatory cascade governed by transcriptional factor NF-κB. Regulation of NF-κB activity is complex, involves several alternative routes, and is also influenced …