Cell Biology Commons^™

Morphological Variation Of Lingual Glands In Wild American Alligator (Alligator Mississippiensis) Populations, Benjamin Angalet

Master's Theses

American alligators (Alligator mississippiensis) inhabit diverse aquatic ecosystems including freshwater wetlands, swamps, and estuarine rivers. As apex predators, their physiological resilience has implications for ecosystem stability and long-term conservation. With projected sea-level rise and increasing saltwater intrusion into coastal freshwater habitats, understanding the osmoregulatory capacity of alligators is increasingly important. Unlike marine-tolerant crocodilians such as the saltwater crocodile (Crocodylus porosus), which possess specialized salt-secreting lingual glands in addition to renal and cloacal mechanisms, the morphology and physiological significance of lingual glands in wild American alligators remain poorly understood. This study examined lingual gland morphology and plasma …

Topodino: Self-Supervised Topological Representation Learning For Neuronal Morphologies, Yasser Binbisher

Master's Theses

Neuronal cell types are categorized by transcriptomic identity, yet their morphological heterogeneity defies this classification. In response, researchers have adopted unsupervised graph representation learning as a tool to reveal morphological variation within single-class transcriptomic types. However, the complex geometry of neuronal morphology—especially long axons and dense dendrites—challenges graph neural networks, which struggle with message propagation across extended structures. To mitigate this, current approaches enforce sub-sampling on neuronal graphs and omit axons entirely, sacrificing critical biological features for computational efficiency. To overcome this trade-off, this thesis introduces TopoDINO, a self-supervised, topology-aware representation learning model designed to preserve the full hierarchical organization …

The Impact Of Growth Hormone-Releasing Hormone Antagonist On Human Adipose-Derived Stem Cells, Jeanne Michelle Dugas

Master's Theses

Obesity is a condition that affects over 40% of American adults and contributes to numerous preventable health issues. This condition is caused by increased adipose tissue, which forms when stem cells transform into adipocytes. Mesenchymal stem cells, including human adipose-derived stem cells (hASC), are multipotent with the ability to differentiate into adipocytes, osteocytes, or chondrocytes. Many factors affect this transformation, including the peptide growth hormone-releasing hormone (GHRH). The main role of GHRH is to trigger the release of growth hormone, but it has also been found to play an important role in adipocyte metabolism. We expect that if the differentiation …

Impact Of Temperature And Microbial Infection On The Honey Bee Hemocytes, Michael E. Oeth

Master's Theses

Introduction

Honey bees (Apis mellifera) rely on hemocytes for immunity, wound healing, and hemolymph homeostasis. While 32°C reflects optimal hive conditions, suboptimal temperatures (22°C) and stressors like pathogens (Varroa destructor, bacteria) or pesticides impair hemocyte function. Using clodronate liposomes (CLD) to deplete hemocytes, we assessed how immune suppression interacts with these stressors.

Methods

Newly emerged (5-day-old) and older (15-day-old) bees were assigned to: CLD, control liposomes (LP), PBS, injection wound, or no treatment. Cohorts were exposed to 32°C (optimal) or 22°C (stressful for non-immunosuppressed bees). Fifteen-day-old bees were challenged with Escherichia coli or Staphylococcus aureus. Survival, hemolymph volume, and hemocyte …

Lack Of Inflammatory Response In Mouse Embryonic Cells To Listeria Infection, Damilola Oyebode

Master's Theses

Approximately 1 in 5 pregnancies in the United States results in miscarriage, with a significant percentage of these losses attributed to failed implantation due to immunological challenges encountered by the early embryo. Recent research has shown that key cell types within mouse blastocysts, including embryonic stem cells (ESCs) and trophoblast stem cells (TSCs), exhibit remarkable resilience against the cytotoxic effects associated with viral infections and embryotoxic cytokines, such as TNFα and IFNγ, both of which are known to hinder blastocyst development. However, the immune properties of the preimplantation stage embryo, specifically the blastocyst, remain poorly understood. Using mouse cell model, …

Regulation Of Sterile Inflammatory Responses By Mitochondria-Associated Proteins, Meghana Venkatesan

Master's Theses

Inflammation is an important defense mechanism through which cells respond to pathogenic insults and damage/stress signals. Immune cells mediate extracellular inflammatory responses by synthesizing and releasing small proteins called cytokines, which play critical roles in modulating these responses. Specifically, key pro-inflammatory cytokines such as IL-1beta are released upon the assembly and activation of a multi-protein intracellular complex called the inflammasome, the most well-studied of which is the NLRP3 inflammasome. Several proteins have been identified as important regulators of cellular stress responses, including vacuole membrane protein 1 (VMP1). The present research shows that VMP1-depleted cells exhibit exacerbated cellular inflammation and are …

Deciphering The Contribution Of Microglia To Neurodegeneration In Friedreich's Ataxia, Sydney N. Gillette

Master's Theses

Friedreich's ataxia (FRDA) is the most prevalent inherited ataxia, affecting one in every 50,000 individuals in the United States. This hereditary condition is caused by an abnormal GAA trinucleotide repeat expansion within the first intron of the frataxin gene resulting in decreased levels of the frataxin protein (FXN). Insufficient cellular frataxin levels results in iron accumulation, increased reactive oxygen species production and mitochondrial dysfunction. Tissues most heavily impacted are those most dependent on oxidative phosphorylation as an energy source and include the nervous system and muscle tissue. This is evident in the clinical phenotype which includes muscle weakness, ataxia, neurodegeneration …

Regulation Of Intracellular Sorting Of The Bruno Protein In Drosophila Flight Muscles, Travis Main

Master's Theses

Understanding mechanisms of intracellular sorting is a fundamental inquiry of cell biology. We used the B-body and protein Bruno (Bru) as a model to study the formation of nuclear domains that are membraneless organelles inside the cell nucleus. Specifically, we sought to identify protein sequences that regulate Bru's affinity to B-bodies and protein aggregation. We generated various Bru mutants and subsequently tested them in vivo using fluorescence microscopy. We found that the protein solubility of Bru is determined through an interplay of RNA recognition motifs (RRMs) and intrinsically disordered regions (IDRs). Using truncation analysis, we identified a 31-amino acid region …

The Role Of B Cell Activation State And Sex In Aryl Hydrocarbon Receptor Mediated Induction Of Chemokine Receptor 9 And Alpha4beta7 Expression In Vitro, Logan Bauerle

Master's Theses

Defense of mucosal tissues from microbial infection and allergy is reliant on continual production of antibodies. The aryl hydrocarbon receptor (AhR) is known to regulate B cell development and is associated with suppression of systemic humoral immunity. Recent attention has been paid to the role of the AhR in altering expression of cell adhesion molecules (CAMs). B cells express CAMs and chemokine receptors to migrate around the body for localized secretion of antibodies. AhR agonists promote B cell migration to the small intestine through upregulation of chemokine receptor 9 (CCR9) and integrin α₄β₇. Both the AhR …

Exploring The Interactions Of Copper High Aspect Ratio Structures (Cuhars), A Novel Metal-Organic Biohybrid Nanocomposite, With Chondrocytes, Tasneem Khasru

Master's Theses

Osteoarthritis (OA) is a prevalent degenerative joint disorder characterized by cartilage lesions and subchondral bone destruction (1). Addressing OA is challenging due to cartilage's avascular and aneural nature, unique cellular arrangement, and dense extracellular matrix (ECM). Current pharmacological treatments are mainly symptomatic and are unable to halt disease progression or reverse cartilage damage . Surgical interventions also come with complications. Tissue-engineered grafts using biomaterials and molecular manipulation have emerged as potential treatments for cartilage regeneration. Copper-containing scaffolds have shown promise in bone and cartilage regeneration. Nanotechnology offers new avenues, with nanoparticles and nanofibers being used in tissue engineering research. However, …

Development Of Wiskott-Aldrich Syndrome Knock Out Protocol For Drug Substance Assay Development, Julia C. Hanna

Master's Theses

Wiskott-Aldrich Syndrome (WAS) is a rare X-linked primary immunodeficiency affecting approximately 1 in 100,000 live XY births in North America and is caused by a mutation to the WAS gene which is expressed across hematopoietic lineages. The WAS protein (WASp) plays a role in regulating actin polymerization. On a cellular level, there are a variety of effects of a lack of WASp or expression of a dysfunctional WASp protein for patients including issues with migration, adhesion, chemotactic response, phagocytosis, activation, and proliferation across different cell types in addition to reduced platelet size and output. This can lead to several systematic …

How To Build A Cortex: Coordinated Assembly Of Cortical Septins And Actomyosin In The Leader Bleb, Asia Marie Paguntalan

Master's Theses

In confined spaces, migrating cells can undergo mesenchymal-to-amoeboid transitions by altering their cortical dynamics and adhesion with the environment. Septins frequently associate with cortical actin and non-muscle myosin (NMII), but the functional nature of these interactions remains unclear. Upon non-adhesive confinement and NMII enrichment, fibroblasts can switch to a fast, leader bleb-based mode of motility, characterized by the absence of adhesions and stress fibers and formation of a single, elongated leader bleb. During this transition, cortical actin remodeling and polarized NMII contractility drive leader bleb stabilization by generating long-range cortical flows, in coordination with changes in septin localization and assembly …

The Role Of Med31 And Med12 In Directing Adipogenesis Of Human Adult-Derived Mesenchymal Stem Cells, Joseph Straub

Master's Theses

Selective gene expression is crucial in maintaining the self-renewing and multipotent properties of stem cells. Mediator is a large, evolutionarily conserved, multisubunit protein complex that modulates gene expression by relaying signals from cell type-specific transcription factors to RNA polymerase II. In humans, this complex consists of 30 subunits arranged in four modules: head, middle, tail, and kinase. In our introduction, we show the state of the field of Mediator study with a focus on the critical kinase module. In the following chapters, we used siRNA knockdowns to investigate the roles of the highly-conserved core subunit MED31 and the kinase module …

The Role Of Med12 In Adipogenesis, Caroline Helen Rinderle

Master's Theses

In order for any function to occur within a cell, transcription factors must be able to interact with genes. When this occurs, genes are expressed, and ultimately, proteins are translated and perform the specific function that needs to be done within the cell. In order for this to occur, genes must interact with transcription machinery. The Mediator complex recruits transcription factors to genes in order to promote cell-type specific gene expression. The Mediator complex is a multi-protein complex consisting of four modules: head, middle, tail, and kinase. The kinase module is known to dissociate from the rest of the complex …

Characterization Of Alcohol-Mediated Promotion Of Breast Cancer Stem Cells, Mckenna Below

Master's Theses

Breast cancer is the leading cause of cancer-related death in women globally, and one in eight women will be diagnosed with breast cancer at some point in her life. Alcohol consumption has been linked to increase breast cancer risk and increased risk of tumor recurrence. Understanding the molecular mechanisms of modifiable lifestyle factors such as alcohol consumption will help to lower these risks and design more effective therapeutic approaches. Estrogen Receptor positive (ER+) breast cancer comprises approximately 70% of all breast cancers, and these tumors are effectively targeted by endocrine therapy in the form of estrogen deprivation with aromatase inhibitors, …

Characterizing Erad And Antioxidant Response In Ixodes Scapularis Ise6 Cells During Borrelia Infection, Latoyia Downs

Master's Theses

Ticks are hematophagous ectoparasites that transmit a multitude of diseases to humans. Borrelia burgdorferi (BB) and Borrelia miyamotoi (BM) are both tick-borne pathogens that cause disease in humans and are transmitted by the black-legged tick (Ixodes scapularis). A byproduct of blood digestion generates reactive oxygen species that are toxic and cause oxidative stress which promotes cellular damage and dysfunction. The endoplasmic reticulum (ER) is especially affected by oxidative stress, resulting in a buildup of improperly folded proteins in the ER lumen called ER stress. To prevent cellular damage, the tick utilizes an antioxidant system to neutralize ROS and mechanisms …

The Democratization And Development Of Cell-Free Protein Synthesis, Max Z. Levine

Master's Theses

Cell-free protein synthesis (CFPS) using crude lysates has developed into a robust platform technology over the last 60 years to express numerous types of recombinant proteins. The open-nature, elimination of reliance on cell viability, and focus of all energy towards production of the protein of interest represent substantial advantages of CFPS over in vivo protein expression methods. CFPS has provided new opportunities across a series of research fields that include metabolic engineering, therapeutic and vaccine development, education, biosensors, and many more. In recent years, optimizations of CFPS have even allowed the platform to reach the industrial level of protein production. …

Development Of A Prolyl Endopeptidase Expression System In Lactobacillus Reuteri To Reduce The Clinical Manifestation Of Celiac Disease, Kara Lynn Jew

Master's Theses

Celiac Disease (CD) is an autoimmune disorder that emerges due to the ingestion of gluten, a protein found in a variety of common grains such as wheat, rye, and barley. Approximately 1 in 100 individuals in the US suffer from CD, making it the most commonly diagnosed gastrointestinal disorder (Ciclitira et. al., 2005). These proline-rich gluten peptides are resistant to proteolysis and accumulate in the duodenum of the small intestine. Once in the duodenum, these peptides illicit an autoimmune response resulting in villous atrophy. Current treatment for CD requires a rigorous adherence to a gluten-free diet. Nevertheless, gluten-containing grains are …

Attenuated Responses To Inflammatory Cytokines In Mouse Embryonic Stem Cells: Biological Implications And The Molecular Basis, Bohan Chen

Master's Theses

Embryonic stem cells (ESCs) have attracted intense interest due to their great potential for regenerative medicine. However, their immune property is an overlooked but a significant issue that needs to be thoroughly investigated not only to resolve the concern for therapeutic applications but also for further understanding the early stage of organismal development. Recent studies demonstrated that ESCs are deficient in innate immune responses to viral/bacterial infections and inflammatory cytokines. Inflammatory conditions generally inhibit cell proliferation, which could be detrimental to ESCs, since cell proliferation is their dedicated task during early embryogenesis. Thus, I hypothesize that the attenuated innate immunity …

Engineering Yeast To Evaluate Human Proteins Involved In Selective Rna Packaging During Hiv Particle Production, Ryan M. Bitter

Master's Theses

Despite recent advances in antiretroviral therapy, nearly 37 million people continue to live with human immunodeficiency virus (HIV). Basic and applied research on the assembly of HIV could be enhanced by using a genetically tractable organism, such as yeast, rather than mammalian cells. While previous studies showed that expression of the HIV Gag polyprotein in Saccharomyces cerevisiae spheroplasts resulted in the production of virus-like particles (VLPs), many questions regarding the utility of yeast in HIV assembly remain uninvestigated. Here, we report use of S. cerevisiae for both the production of VLPs with selectively packaged RNA and to evaluate the human …

Evaluation Of Endothelial Cell Responses To Elevated Glucose, Gabriella Sugerman

Master's Theses

Developing a tissue-engineered Blood Vessel Mimic (BVM) to represent diabetic macrovascular disease could expedite design of new vascular devices specifically tailored to diabetic patients. In contribution toward this model, this thesis assessed Human Umbilical Vein Endothelial Cell (HUVEC) responses to high glucose conditions. Interleukin 6 (IL-6) and Cluster of Differentiation 36 (CD36) were selected to signify oxidative stress activity, a hallmark of diabetic macrovascular disease. Next, activity of potential reference genes B2M, HPRT1, and ACTB was assessed. All genes were found to exceed acceptable variability, so the E-ΔC T method of data analysis was selected. Next, cellular responses to high …

Investigating Autophagy, Extracellular Vesicles, And Glycobiology, Benjamin Cook

Master's Theses

Autophagy is a cellular process of degradation which degrades cellular materials in acidic organelles called lysosomes. Impairment of lysosomal degradation can lead to lysosomal storage disorders such as Parkinson's Disease. In Parkinson's Disease neurotoxic α-synuclein can spread from cell-to-cell via extracellular vesicles. We investigated the changes in extra vesicular glycans upon perturbation of autophagy using a class of glycan binding molecules termed lectins.

We found that upon induction of autophagy causes EV glycans to increase while others remained consistent. Additionally, we found that specific glycans are increased more than others. Conversely, when lysosomal degradation was impaired, we observed a decrease …

Proteomic Analysis Of The Crustacean Molting Gland (Y-Organ) Over The Course Of The Molt Cycle, Talia B. Head

Master's Theses

Molting in crustaceans is a highly complex physiological process involving negative regulation by two paired endocrine glands, the X-organ/sinus gland complex (XO/SG) and the Y-organ (YO). The XO/SG complex is responsible for making molt-inhibiting hormone (MIH) which negatively regulates synthesis of the molting hormones, ecdysteroids, by the YO. Analysis of gene expression in the XOs and YOs has led to the development of a proposed molecular signaling pathway which regulates ecdysteroidogenesis and subsequent molting in crustaceans. In this study, changes in protein abundance in the YO were characterized over the course of a molt cycle (intermolt, early premolt, mid premolt, …

Effect Of Oxygen-Limiting Tidal Conditions On Muscle Metabolism And Structure In The Giant Acorn Barnacle, Balanus Nubilus, Katie O. Grady

Master's Theses

Crustacean muscle fibers are some of the largest cells in the animal kingdom, with fiber diameters in the giant acorn barnacle (Balanus nubilus) exceeding 3 mm. Sessile animals with extreme muscle sizes and that live in the hypoxia-inducing intertidal zone – like B. nubilus – represent ideal models for probing the effects of oxygen limitation on muscle cells. We investigated changes in metabolism and structure of B. nubilus muscle in response to: normoxic immersion, anoxic immersion, or air emersion, for acute (6h) or chronic (6h exposures twice daily for 2wks) time periods. Following exposure, we immediately measured hemolymph …

Reconstitution Of Munc18-Dependent Mast Cell Degranulation, Matthew Grant Arnold

Master's Theses

Mast cells are specialized secretory leukocytes that play diverse roles in the body, mediated by release of histamine and other pharmacologically active substances. Although offering essential protection in innate and adaptive immunity, mast cells are also essential to the progression of inflammatory diseases, including allergy and asthma, (Theoharides et al., 2012). Exocytosis of pro-inflammatory mast cell mediators in response to otherwise innocuous antigens relies on evolutionarily-conserved membrane fusion machinery. These proteins, called SNAREs are regulated by the Sec1/Munc18 (SM) protein family (Axle Lorentz, Baumann, Vitte, & Blank, 2012). Mast cells express three mammalian Munc18 isoforms (a, b, and c), which …

Deciphering The Functional Collaboration Of Mid And Bric-A-Brac 2 As Potential Regulators Of Cellular Proliferation Within Adult Drosophila Ovaries, Petra Visic

Master's Theses

Stem cell niches are highly organized and specialized microenvironments located within specific tissues of both vertebrate and invertebrate organisms [1]. In Drosophila melanogaster, three distinct stem cell niches have been identified within the ovary including the germline stem cell (GSC), follicle stem cell (FSC), and escort stem cell (ESC) niche. Recently, Fregoso-Lomas et al. [2] reported that Gurken/Epidermal Growth Factor Receptor (EGFR) signaling is modulated within posterior ovarian follicle cells by Midline (Mid). The mid gene encodes a T-box transcription factor protein that specifies cell fates in the developing heart [3][4], central nervous system [5][6], epidermis [7], and eye …

Utilizing Galectin 3 As A Marker Of Ruptured Vesicles In Vivo, Jonathan London

Master's Theses

Ruptured vesicles have been associated with pathological forms of α-synuclein during the development of PD. Galectin 3 (Gal3) is readily recruited to these ruptured vesicles, making it a potentially useful marker of vesicle rupture in PD and other diseases associated with vesicle rupture and lysosomal dysfunction. We were able to visualize and quantify the differences in Gal3 levels during infection with pathological α-synuclein in the rat brain. Having significantly high basal levels of Gal3, we found that the differentiated monocytes showed a nearly100 percent increase in intercellular levels of Gal3 after treatment with pathological α-synuclein. By expressing only the Carbohydrate …

Identification And Characterization Of Msab Gene Involved In Biofilm Formation And Virulence In Staphylococcus Aureus, Amelsaad Elbarasi

Master's Theses

Staphylococcus aureus is an important human pathogen that causes a wide variety of life-threatening infections ranging from minor skin and oral infections to severe infections, such as bacteremia, pneumonia, osteomyelitis, or endocarditis due to the presence and secretion of a large number of virulence factors that are controlled by global virulence regulators in complex networks. Furthermore, S. aureus infections have become a threat to public health because of their high potential to form biofilm, and their ability to resist a wide range of antibiotics has exacerbated further. Therefore, understanding the regulatory networks and developing a drug targeting these networks has …

Role Of Msaa Gene In Regulation Of The Msaabcr Operon And Biofilm Development In Staphylococcus Aureus, Ahmed Alzuway

Master's Theses

Staphylococcus aureus is an important human pathogen that causes wide variety of diseases ranging from chronic biofilm associated infection to acute life threatening infection such as bacteremia, pneumonia, osteomyelitis, or endocarditis, despite the progress with antibiotics used in the treatment of bacterial infections. Furthermore, increased use of prosthetic and indwelling devices in modern medical practices has led to increased infections due to S. aureus. Treating S. aureus infections have become difficult owing to its ability to resist most of the antibiotics; this problem is further exacerbated by ability of MRSA strains to form biofilms. Emergence of community-acquired methicillin resistance …

Protective Effects Of Sphingomyelin Against Uv Photodamage In Human Keratinocytes, Kathleen De Guzman

Master's Theses

Ultraviolet (UV) radiation has been demonstrated in numerous studies to be a major risk factor for non-melanoma skin cancer development. Despite the emergence of current UV-preventative strategies, such as sunscreens and skin-protective clothing, the incidence of non-melanoma skin cancer has continued to rise. This has encouraged investigations on alternative methods for UV prevention. In particular, bovine milk sphingomyelin has been studied for its potential in protecting human skin against UV photodamage. While the previous studies have suggested that sphingomyelin exhibits UV-protective properties in a human skin equivalent model, the exact mechanisms behind sphingomyelin’s photoprotective effects are yet unknown.

This thesis …