Medical Cell Biology Commons^™

It's A Hard Nacht Life: Understanding How Nlrp12 Ticks, Abbigale Julia Brown

Graduate Theses/Dissertations

The protein NOD- like receptor pyrin domain containing 12 (NLRP12) comes from a family of protein receptors with a wide range of functions including fertility as well as anti-inflammatory properties. The biological role of NLRP12 is poorly understood: research on the mechanisms behind its function and/or activation remains contradictory between different cell models. Current research suggests its involvement in a multi-protein complex named the inflammasome. The alternative hypothesis that has also been proposed is that NLRP12 is not a part of the inflammasome, rather it negatively regulates a transcription factor known as NF-��B down stream of Toll-like receptors. NLRP12 is …

Identification And Molecular Analysis Of Dna In Exosomes, Jena Tavormina

Dissertations and Theses (Open Access)

Exosomes are heterogeneous nanoparticles 50-150nm in diameter. Exosomes contain many functional cargo components, such as protein, DNA, and RNA. While protein and RNA exosome content has been extensively studied, very little work has been done to characterize exosomal DNA. Here, we demonstrate that exosomal DNA is heterogeneous and its packaging into exosomes is dependent on the cell of origin. Furthermore, through a rigorous assessment of various isolation methods, we identify Size Exclusion Chromatography (SEC) as the best method for the isolation of exosomal DNA for downstream applications. Additionally, we evaluate the methylation status of exosomal DNA and demonstrate that exosomal …

Natural Autoantibodies: Origin, Function And Utility For Diagnosis Of Disease, Abhirup Sarkar

Graduate School of Biomedical Sciences Theses and Dissertations

Autoantibodies (aAbs) by the simplest definitions have been described as antibodies against self-antigens and were exclusively associated with autoimmune diseases. Eventually, studies demonstrated that they are abundant in the blood of all human sera, regardless of age, gender, or the presence or absence of disease, and were thus named as ‘natural autoantibodies’. The underlying reason for their ubiquity has remained elusive, but we have hypothesized that they are responsible for clearing blood-borne cell and tissue debris generated under conditions of health and disease. To test this, we chose to use two widely different disease model systems, namely neurodegenerative diseases and …

Regulation Of Na-K-Atpase By Arachidonic Acid Metabolites In Intestinal Epithelial Cells, Niraj Nepa

Theses, Dissertations and Capstones

The integral membrane protein sodium potassium adenosine triphosphate (Na-K-ATPase), has been extensively studied in various animal cell models. Na-K-ATPase is a multifunctional enzyme which plays a significant role in cellular physiology by regulating electrochemical potential, cell volume, pH, cytosolic calcium, and many nutrient and electrolyte transport processes. As such, it has been implicated in the pathogenesis of inflammatory bowel diseases (IBD) and has been shown to play a vital role in the malabsorption of nutrients and electrolytes. In this context, a significant amount of research has been done over the last two decades to understand the mechanisms of alteration of …

Endogenous Antioxidant Overexpression As An Adjuvant To Diet Or Exercise Intervention As Therapy To Counteract Obesity And Beneficially Shift The Gut Microbiome, Deborah Lynn Amos

Theses, Dissertations and Capstones

Oxidative stress plays a key role in metabolic syndrome which includes obesity and cardiometabolic diseases. It is implicated that oxygen-derived free radicals generated during the mitochondrial electron transport chain alter the function of specific biological components, thus activating obesogenic pathways such as glucose and lipid signaling. Research on this topic is of vital importance as obesity is a high-risk factor in the development and progression of severe, debilitating, life-threatening maladies such as cardiometabolic diseases, chronic inflammatory pathologies, and cancer. Furthermore, there is no universal effective therapy to combat the rising rates of obesity with over 1.9 billion (39%) adults classified …

Understanding Pseudomonas Aeruginosa Alginate Regulation And Its Link To Chronic Lung Infections In Cystic Fibrosis Patients, Roy Al Ahmar

Theses, Dissertations and Capstones

Cystic Fibrosis (CF) is a genetic disorder caused by mutations in the gene encoding Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). This disorder results in thick lung secretions which compromise the patient’s immune system. Chronic lung infections with Pseudomonas aeruginosa biofilms is a major factor that contributes to poor outcome for clinical treatment. The overall hypothesis of this dissertation is that small colony variant and pyrimidine biosynthesis are linked with biofilm formation, alginate production is dependent on MucA proteolysis, rifaximin can be repurposed to treat biofilm infection and multiplex PCR can be used to rapidly measure the bacterial cell density in …

An Ensemble Of Flexible Conformations Underlies Mechanotransduction By The Cadherin–Catenin Adhesion Complex, Martin Bush, Bashir M. Alhanshali, Shuo Qian, Christopher B. Stanley, William T. Heller, Tsutomu Matsui, Thomas M. Weiss, Iain D. Nicholl, Thomas Walz, David J. E. Callaway, Zimei Bu

Publications and Research

The cadherin–catenin adhesion complex is the central component of the cell–cell adhesion adherens junctions that transmit mechanical stress from cell to cell. We have determined the nanoscale structure of the adherens junction complex formed by the α-catenin•β-catenin•epithelial cadherin cytoplasmic domain (ABE) using negative stain electron microscopy, small-angle X-ray scattering, and selective deuteration/small-angle neutron scattering. The ABE complex is highly pliable and displays a wide spectrum of flexible structures that are facilitated by protein-domain motions in α- and β-catenin. Moreover, the 107-residue intrinsically disordered N-terminal segment of β-catenin forms a flexible “tongue” that is inserted into α-catenin and participates in the …

Mesenchymal Stromal Cell Therapeutic Delivery: Translational Challenges To Clinical Application, Henry Caplan, Scott D Olson, Akshita Kumar, Mitchell George, Karthik S Prabhakara, Pamela Wenzel, Supinder Bedi, Naama E Toledano-Furman, Fabio Triolo, Julian Kamhieh-Milz, Guido Moll, Charles S Cox

Faculty, Staff and Student Publications

For several decades, multipotent mesenchymal stromal cells (MSCs) have been extensively studied for their therapeutic potential across a wide range of diseases. In the preclinical setting, MSCs demonstrate consistent ability to promote tissue healing, down-regulate excessive inflammation and improve outcomes in animal models. Several proposed mechanisms of action have been posited and demonstrated across an array of in vitro models. However, translation into clinical practice has proven considerably more difficult. A number of prominent well-funded late-phase clinical trials have failed, thus calling out for new efforts to optimize product delivery in the clinical setting. In this review, we discuss novel …

Roles Of Cytosolic Nucleic Acid Sensors In Cancer And Infection, Qifan Zhu

Theses and Dissertations (ETD)

Pattern recognition receptors are innate immune sensors that recognize pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs) with crucial roles in host defense against microbial infection, autoimmune diseases and cancer. Cytosolic nucleic acids including DNA and RNA originate from pathogens or self-cells, which form major groups of PAMPs and DAMPs. A range of nucleic acid sensors have evolved to sense various types of nucleic acids. How different DNA-sensing pathways regulate microbial infection and cancer is the focus of this dissertation.

Stimulator of IFN genes (STING) is a cytosolic innate immune sensor for cyclic dinucleotides that also serves a dual …

Escherichia Coli Itat Is A Type Ii Toxin That Inhibits Translation By Acetylating Isoleucyl-Trnaile, Brendan Wilcox, Ilya Osterman, Marina Serebryakova, Dmitry Lukyanov, Ekaterina Komarova, Bridget Gollan, Natalia Morozova, Yuri I Wolf, Kira S Makarova, Sophie Helaine, Petr Sergiev, Svetlana Dubiley, Sergei Borukhov, Konstantin Severinov

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Prokaryotic toxin-antitoxin (TA) modules are highly abundant and are involved in stress response and drug tolerance. The most common type II TA modules consist of two interacting proteins. The type II toxins are diverse enzymes targeting various essential intracellular targets. The antitoxin binds to cognate toxin and inhibits its function. Recently, TA modules whose toxins are GNAT-family acetyltransferases were described. For two such systems, the target of acetylation was shown to be aminoacyl-tRNA: the TacT toxin targets aminoacylated elongator tRNAs, while AtaT targets the amino acid moiety of initiating tRNAMet. We show that the itaRT gene pair from Escherichia coli …

Uplc-Ms/Ms Analysis Of Dextromethorphan-O-Demethylation Kinetics In Rat Brain Microsomes, Barent N. Dubois, Reza Mehvar

Pharmacy Faculty Articles and Research

Formation of dextrorphan (DXT) from dextromethorphan (DXM) has been widely used to assess cytochrome P450 2D (CYP2D) activity. Additionally, the kinetics of CYP2D activity have been well characterized in the liver microsomes. However, studies in brain microsomes are limited due to the lower microsomal content and abundance of CYP2D in the brain relative to the liver. In the present study, we developed a micro-scale enzymatic incubation method, coupled with a sensitive UPLC-MS/MS assay for the quantitation of the rate of DXT formation from DXM in brain microsomes. Rat brain microsomes were incubated with different concentrations of DXM for various times. …

Inhibition Of Ribosome Biogenesis Through Genetic And Chemical Approaches, Leonid Anikin

Graduate School of Biomedical Sciences Theses and Dissertations

In order to maintain the ability to generate proteins, proliferating cells must continuously generate ribosomes, designating up to 80% of their energy to ribosome biogenesis (RBG). RBG involves transcription of rDNA by RNA polymerases I (Pol I) and III (Pol III), expression of approximately 80 ribosomal proteins, and assembly of these components in a process referred to as ribosome maturation. During maturation, the Pol I transcribed 47S pre-rRNA undergoes a number of processing events, while simultaneously interacting with processing factors and ribosomal proteins that drive pre-ribosome assembly. Inhibition of RBG has become one of the pursued targets for cancer therapy …

The Zinc Transporter Zipt-7.1 Regulates Sperm Activation In Nematodes, Yanmei Zhao, Chieh-Hsiang Tan, Amber Krauchunas, Andrea Scharf, Nicholas Dietrich, Kurt Warnhoff, Zhiheng Yuan, Marina Druzhinina, Sam Guoping Gu, Long Miao, Andrew Singson, Ronald E Ellis, Kerry Kornfeld

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Sperm activation is a fascinating example of cell differentiation, in which immotile spermatids undergo a rapid and dramatic transition to become mature, motile sperm. Because the sperm nucleus is transcriptionally silent, this transition does not involve transcriptional changes. Although Caenorhabditis elegans is a leading model for studies of sperm activation, the mechanisms by which signaling pathways induce this transformation remain poorly characterized. Here we show that a conserved transmembrane zinc transporter, ZIPT-7.1, regulates the induction of sperm activation in Caenorhabditis nematodes. The zipt-7.1 mutant hermaphrodites cannot self-fertilize, and males reproduce poorly, because mutant spermatids are defective in responding to activating …

Defining The Radioresponse Of Mossy Cells, Devon Ivy

Electronic Theses, Projects, and Dissertations

Clinical radiotherapy is used to treat a variety of brain tumors within the central nervous system. While effective, it can result in progressive and debilitating cognitive impairment that can diminish quality of life. These impairments have been linked to hippocampal dysfunction and corresponding deficits in spatial learning and memory. Mossy cells are a major population of excitatory neurons located within the dentate hilus and highly involved in hippocampal circuitry. They play critical roles in spatial navigation, neurogenesis, memory, and are particularly vulnerable to a variety of neurotoxic insults. However, their sensitivity to ionizing radiation has yet to be investigated in …

Till Death Do Us Part: The Marriage Of Autophagy And Apoptosis., Katrina F Cooper

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Autophagy is a widely conserved catabolic process that is necessary for maintaining cellular homeostasis under normal physiological conditions and driving the cell to switch back to this status quo under times of starvation, hypoxia, and oxidative stress. The potential similarities and differences between basal autophagy and stimulus-induced autophagy are still largely unknown. Both act by clearing aberrant or unnecessary cytoplasmic material, such as misfolded proteins, supernumerary and defective organelles. The relationship between reactive oxygen species (ROS) and autophagy is complex. Cellular ROS is predominantly derived from mitochondria. Autophagy is triggered by this event, and by clearing the defective organelles effectively, …

Muc4 Based Immunotherapy For Pancreatic Cancer, Kasturi Banerjee

Theses & Dissertations

Pancreatic Cancer (PC) is a lethal disease claiming approximately 45000 lives in the US in 2018, and it establishes an elaborate immunosuppressive tumor microenvironment that aids in disease pathogenesis. Immunotherapy has emerged as a strategy to target tumor cells by reprogramming patient’s immune system. Challenges present in PC immunotherapy are: i) identifying a tumor-associated antigen that could be targeted, ii) identifying adjuvants that could efficiently deliver antigens, iii) eliciting robust anti-tumor responses and iv) overcoming peripheral tolerance and immunosuppression elicited by the tumor.

Firstly, we detected circulating autoantibodies to MUC4 present in PC patients and observed that IgM autoantibodies to …

Role Of Smarce1 And Bhlhe40 In Breast Cancer Metastasis, Aarti Sethuraman

Theses and Dissertations (ETD)

No abstract provided.

Protein Trafficking Of Bk Channel Β1 Subunits In Cerebral Artery Myocytes, Xue Zhai

Theses and Dissertations (ETD)

Rationale: Large-conductance calcium (Ca²⁺)-activated potassium channels (BK) are expressed in arterial myocytes to control arterial contractility. It is composed of pore- forming BKα and auxiliary β1 subunits. Auxiliary β1 subunits associate with BKα which modulate Ca²⁺ sensitivity of BK channel. Previous data showed that BKα locates at cell membrane, whereas β1 subunits are primarily intracellular which regulated by Rab11A- positive recycling endosomes. Endothelin-1 (ET-1), a vasoconstrictor, induces contraction of myocytes. ET-1 inhibits BK channel but mechanisms are not fully understood. It is unclear that vasoconstrictors regulate the cellular distribution of BK channels. Furthermore, BK channels are involved …

Factors Involved In Suppression Of Human Vγ9vδ2 T-Lymphocytes And Impact Of Checkpoint Blockades On The Effector Functions Of Vγ9vδ2 T-Lymphocytes, Minji Choi, Andrew Wiemer, Andrea Hubbard, Brian Aneskievich

University Scholar Projects

Chronic antigenic stimulation leads to T cell exhaustion, which drastically dampens T cell effector functions. Upon exhaustion, T cells progressively lose their proliferative capacity, cytokine production, and cytotoxic effector functions against tumors. T cell exhaustion involves programmed cell death-1 (PD-1), which is an inhibitory co-stimulation receptor. Limited scope of studies has been done regarding impact of PD-1 expression on the effector functions of γδ T cells. In this study, we investigated expression of PD-1 and its impact on effector functions of human γδ T cells. When γδ T cells were stimulated with phosphoantigens (HMBPP and POM₂-C-HMBP) and analyzed …

Role Of Oxidized Extracellular Vesicles As Early Biomarkers And Inflammatory Mediators In Chemotherapy-Induced Normal Tissue Injury, Chontida Yarana

Theses and Dissertations--Toxicology and Cancer Biology

Significant advances in the efficacy of cancer therapy have been accompanied by an escalation of side effects that result from therapy-induced injury to normal tissues. Patients with high grade cancer or metastasis are often treated with chemotherapy, 50% of which are associated with reactive oxygen species generation and cellular oxidative stress. Heart is the normal tissue most susceptible to chemotherapy-induced oxidative stress and heart disease is the most common leading cause of death in cancer survivors. However, early and sensitive biomarkers to identify heart disease are still lacking. Extracellular vesicles (EVs) are released from cells during oxidative stress and send …

Arl2bp, A Novel Ciliopathy Protein, Is Required For Cilia Microtubule Formation, Abigail Ruth Moye

Graduate Theses, Dissertations, and Problem Reports (ETD)

Cilia are specialized organelles essential for cellular function. Not surprisingly, mutations in cilia- related genes are linked to multi-syndromic diseases termed ciliopathies. These include blinding diseases such as retinitis pigmentosa (RP). One such novel gene is ARL2BP (ARL2-binding protein) and is linked to RP and situs inversus (organ reversal) in humans, a phenotype produced by defects in the nodal cilia of developing embryos. Defects in photoreceptor cilia, as well as situs inversus in human patients, suggest that ARL2BP plays an invaluable role in the structure and function of cilia. However little is known about the role for this protein in …

A Simple And Accurate Rule-Based Modeling Framework For Simulation Of Autocrine/Paracrine Stimulation Of Glioblastoma Cell Motility And Proliferation By L1cam In 2-D Culture., Justin Caccavale, David Fiumara, Michael Stapf, Liedeke Sweitzer, Hannah J. Anderson, Jonathan Gorky, Prasad Dhurjati, Deni S. Galileo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Glioblastoma multiforme (GBM) is a devastating brain cancer for which there is no known cure. Its malignancy is due to rapid cell division along with high motility and invasiveness of cells into the brain tissue. Simple 2-dimensional laboratory assays (e.g., a scratch assay) commonly are used to measure the effects of various experimental perturbations, such as treatment with chemical inhibitors. Several mathematical models have been developed to aid the understanding of the motile behavior and proliferation of GBM cells. However, many are mathematically complicated, look at multiple interdependent phenomena, and/or use modeling software not freely available to the research …

Evaluating The Therapeutic Effect Of Purslane Extract On The Submandibular Salivary Glands Of Cyclosporine-A Treated Rats, Heba Mahmoud, Rabab T. Mubarak, Iman M. Aboushady

Dentistry

Salivary glands are affected by immunosuppressive drugs, like Cyclosporine-A (CsA) which plays a major role in transplant medicine. Thus, this work aimed to study the possible therapeutic effect of purslane on CsA induced salivary gland alterations.

Materials & Methods: 30 adult male albino rats were equally divided into 3 groups: control group ] received a vehicle, CsA group received 20 mg/kg/day of CsA, and combination group received CsA and 400mg/kg/day of purslane. Three weeks later rats were sacrified then the submandibular salivary glands were prepared for histological andKi67 immunohistochemical analysis, then the studied groups were statistically evaluated.

Results: Histological examination …

Effect Of Extracellular Survivin And Lymphoma Exosomes On Natural Killer Cells, Heather R. Ferguson Bennit

Loma Linda University Electronic Theses, Dissertations & Projects

Tumors alter their microenvironment to promote survival using methods such as angiogenesis promotion, growth signals, and immune suppression. The immune system becomes unresponsive to transformed neoplastic cells through a variety of methods including T cell suppression, increased myeloid-derived suppressor cells (MDSCs), and reduced natural killer (NK) cell activity. NK cells have inherent killing capabilities and thus are among the first responders in recognizing and destroying abnormal cells. However, many types of cancers inhibit the surveillance and cytotoxic abilities of NK cells by releasing exosomes, vesicles that can modulate the tumor microenvironment (TME) and intercellular communication for the purpose of enhancing …

Inhibition Of Post-Transcriptional Steps In Ribosome Biogenesis Confers Cytoprotection Against Chemotherapeutic Agents In A P53-Dependent Manner, Russell T Sapio, Anastasiya N Nezdyur, Matthew Krevetski, Leonid Anikin, Vincent J Manna, Natalie Minkovsky, Dimitri G Pestov

Rowan-Virtua School of Osteopathic Medicine Departmental Research

The p53-mediated nucleolar stress response associated with inhibition of ribosomal RNA transcription was previously shown to potentiate killing of tumor cells. Here, we asked whether targeting of ribosome biogenesis can be used as the basis for selective p53-dependent cytoprotection of nonmalignant cells. Temporary functional inactivation of the 60S ribosome assembly factor Bop1 in a 3T3 cell model markedly increased cell recovery after exposure to camptothecin or methotrexate. This was due, at least in part, to reversible pausing of the cell cycle preventing S phase associated DNA damage. Similar cytoprotective effects were observed after transient shRNA-mediated silencing of Rps19, but not …

Ubqln1 : A Multi-Domain Protein With Multiple Functions., Zimple Kurlawala

Electronic Theses and Dissertations

There are 5 Ubiquilin proteins (UBQLN1-4, UBQLN-L), which are evolutionarily conserved and structurally similar. UBQLN proteins have 3 functional domains: N-terminal ubiquitin-like domain (UBL), C-terminal ubiquitin-associated domain (UBA) and STI chaperone-like regions in the middle. Alterations in UBQLN1 gene have been detected in a variety of disorders including Alzheimer’s disease, Amyotropic Lateral Sclerosis and lung cancer. UBQLN1 has been largely studied in neurodegenerative disorders in the context of protein quality control. Several studies have hypothesized that the UBA domain of UBQLN1 binds to poly-ubiquitin chains of substrate and shuttles it to the proteasome via its UBL domain for degradation. UBQLN1 …

Mdm2 Is Required For Survival And Growth Of P53-Deficient Cancer Cells., Kyle P Feeley, Clare M. Adams, Ramkrishna Mitra, Christine M. Eischen

Department of Cancer Biology Faculty Papers

p53 deletion prevents the embryonic lethality of normal tissues lacking Mdm2, suggesting that cells can survive without Mdm2 if p53 is also absent. Here we report evidence challenging this view, with implications for therapeutically targeting Mdm2. Deletion of Mdm2 in T-cell lymphomas or sarcomas lacking p53 induced apoptosis and G₂ cell-cycle arrest, prolonging survival of mice with these tumors. p53^-/- fibroblasts showed similar results, indicating that the effects of Mdm2 loss extend to pre-malignant cells. Mdm2 deletion in p53^-/- cells upregulated p53 transcriptional target genes that induce apoptosis and cell-cycle arrest. Mdm2 deletion also increased levels of …

The Role Of Tgf-Β In Ctb-Insulin Regulated Human Dendritic Cell Tolerance, Grace Edosewe Esebanmen

Loma Linda University Electronic Theses, Dissertations & Projects

Cholera toxin B subunit fusion to autoantigen vaccines such as proinsulin (CTB-INS) down regulates dendritic cell (DC) activation and induces the synthesis of DC immunosuppressive cytokines. Recent studies of CTB-INS induction of immune tolerance in human DCs indicate that increased IDO1 biosynthesis may play an important role in CTB-INS vaccine inhibition of DC activation. Previous studies suggest transforming growth factor beta (TGF-β) may play a role in the stimulation of IDO1 biosynthesis for induction of immunological tolerance in murine DCs. To elucidate the mechanisms by which CTB-INS may stimulate IDO1 biosynthesis and mediate tolerance in human DCs, we investigated the …

Determination Of The Effects That A Previously Uncharacterized Secreted Product From Klebsiella Pneumoniae Has On Citrobacter Freundii And Enterobacter Cloacae Biofilms, Cody M. Hastings

Undergraduate Honors Theses

More so than ever, Multiple Drug Resistant (MDR) bacteria are on the rise due to overuse of antibiotics along with natural selection for adaptations that enhance drug-resistant properties. One particular bacterial family, Enterobacteriaceae, has been problematic, exhibiting several bacterial members that have developed a precipitous resistance to modern antibiotics and are also primary causative agents of nosocomial, or hospital acquired, infections. Citrobacter freundii (CF) and Enterobacter cloacae (ECL) are two species of the Enterobacteriaceae family causing significant medical concern due to their role in producing numerous opportunistic infections such as bacteremia, lower respiratory tract infections, urinary tract infections, and endocarditis. …

Role Of Dendritic Cells In Pathology Of Respiratory Syncytial Virus Infection In Neonates, Bishwas Shrestha

Theses and Dissertations (ETD)

Respiratory syncytial virus (RSV) is one of the leading causes of bronchiolitis in children. We have shown that neonatal mice respond to primary RSV infection with T helper type 2 (Th2) biased immune responses, which are enhanced following reinfection. Dendritic cells (DCs) including myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) play important roles in driving host responses to RSV infection. mDCs present antigens to help Th cells differentiate, and pDCs protect against viral infection through type I interferons (IFNs). Despite data demonstrating importance of mDCs and pDCs in protection against RSV, it has not been studied in an age appropriate …