Medical Specialties Commons^™

Functional Determination Of Calcium-Binding Sites Required For The Activation Of Inositol 1,4,5-Trisphosphate Receptors, Vikas Arige, Lara E Terry, Larry E Wagner, Sundeep Malik, Mariah R Baker, Guizhen Fan, Suresh K Joseph, Irina I Serysheva, David I Yule

Journal Articles

Inositol 1,4,5-trisphosphate receptors (IP3Rs) initiate a diverse array of physiological responses by carefully orchestrating intracellular calcium (Ca2+) signals in response to various external cues. Notably, IP3R channel activity is determined by several obligatory factors, including IP3, Ca2+, and ATP. The critical basic amino acid residues in the N-terminal IP3-binding core (IBC) region that facilitate IP3 binding are well characterized. In contrast, the residues conferring regulation by Ca2+ have yet to be ascertained. Using comparative structural analysis of Ca2+-binding sites identified in two main families of intracellular Ca2+-release channels, ryanodine receptors (RyRs) and IP3Rs, we identified putative acidic residues coordinating Ca2+ …

Defining The Cooperation Between Mhc-I And Mhc-Ii Neoantigen-Driven T Cell Responses To Develop Effective Personalized Immunotherapies, Charmelle Williams

Dissertations & Theses (Open Access)

Immune checkpoint therapy (ICT) (e.g. anti-CTLA-4 (α-CTLA-4), anti-PD-1 (α-PD-1)) enables durable T cell-dependent anti-tumor immunity in certain cancer patients. Since a subset of patients respond to ICT, this work aims at developing a more in-depth understanding of T-cell responses to MHC class I (MHC-I) and MHC class II (MHC-II) tumor antigens that are derived from aberrant expression of non-mutant antigens or driver and passenger somatic alterations that can function as tumor neoantigens. We used a poorly immunogenic Braf^v600e Pten^-/- Cdkn2a^-/- YUMM1.7 (Y1.7) murine melanoma line with a paucity of endogenous neoantigens that is unresponsive to ICT, and …

The Role Of The Hypoxia-Inducible Factor 2 In Pancreatic Cancer: Mechanisms Of Tumor Immunosuppression And Intestinal Radioprotection, Carolina Garcia Garcia

Dissertations & Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with dismal prognosis. The only curative option for patients is surgery, but over 80% of patients are not surgical candidates. Unfortunately, PDAC is resistant to the three remaining options. PDAC is characterized by a profoundly hypoxic and immunosuppressive stroma, which contributes to its therapeutic recalcitrance. Alpha-smooth muscle actin+ (αSMA+) cancer-associated fibroblasts (CAFs) are the most abundant stromal component, as well as mediators of stromal deposition. The hypoxia-inducible factors (HIF1 and HIF2) coordinate responses to hypoxia, yet, despite their known association to poor patient outcomes, their functions within the PDAC tumor microenvironment (TME) …

Preventing Cholesterol-Induced Perk (Protein Kinase Rna-Like Endoplasmic Reticulum Kinase) Signaling In Smooth Muscle Cells Blocks Atherosclerotic Plaque Formation, Abhijnan Chattopadhyay, Pujun Guan, Suravi Majumder, Kaveeta Kaw, Zhen Zhou, Chen Zhang, Siddharth K Prakash, Anita Kaw, L Maximillian Buja, Callie S Kwartler, Dianna M Milewicz

Journal Articles

BACKGROUND: Vascular smooth muscle cells (SMCs) undergo complex phenotypic modulation with atherosclerotic plaque formation in hyperlipidemic mice, which is characterized by de-differentiation and heterogeneous increases in the expression of macrophage, fibroblast, osteogenic, and stem cell markers. An increase of cellular cholesterol in SMCs triggers similar phenotypic changes in vitro with exposure to free cholesterol due to cholesterol entering the endoplasmic reticulum, triggering endoplasmic reticulum stress and activating Perk (protein kinase RNA-like endoplasmic reticulum kinase) signaling.

METHODS: We generated an SMC-specific

RESULTS: SMC-specific deletion of Perk reduces atherosclerotic plaque formation in male hyperlipidemic mice by 80%. Single-cell transcriptomic data identify 2 …

Biochemical, Biophysical, And Immunological Characterization Of Respiratory Secretions In Severe Sars-Cov-2 Infections, Michael J Kratochvil, Gernot Kaber, Sally Demirdjian, Pamela C Cai, Elizabeth B Burgener, Nadine Nagy, Graham L Barlow, Medeea Popescu, Mark R Nicolls, Michael G Ozawa, Donald P Regula, Ana E Pacheco-Navarro, Samuel Yang, Vinicio A De Jesus Perez, Harry Karmouty-Quintana, Andrew M Peters, Bihong Zhao, Maximilian L Buja, Pamela Y Johnson, Robert B Vernon, Thomas N Wight, Carlos E Milla, Angela J Rogers, Andrew J Spakowitz, Sarah C Heilshorn, Paul L Bollyky

Journal Articles

Thick, viscous respiratory secretions are a major pathogenic feature of COVID-19, but the composition and physical properties of these secretions are poorly understood. We characterized the composition and rheological properties (i.e., resistance to flow) of respiratory secretions collected from intubated COVID-19 patients. We found the percentages of solids and protein content were greatly elevated in COVID-19 compared with heathy control samples and closely resembled levels seen in cystic fibrosis, a genetic disease known for thick, tenacious respiratory secretions. DNA and hyaluronan (HA) were major components of respiratory secretions in COVID-19 and were likewise abundant in cadaveric lung tissues from these …

Leveraging Single Cell Technologies For The Characterization And Treatment Of Refractory Pancreatic Cancer, Maria Monberg

Dissertations & Theses (Open Access)

Heterogeneity is a hallmark of cancer, and the advent of multimodal single-cell technologies has helped uncover heterogeneity in a high-throughput manner in different cancers across varied contexts at an unprecedented resolution. In an effort to improve precision medicine approaches in pancreatic ductal adenocarcinoma (PDAC), a highly lethal malignancy with a mere 11% 5-year survival rate, this dissertation focuses on first questioning the assumptions of the most basic models used to study PDAC via multimodal single-cell characterization methods at multiple levels of biological organization (scCNVseq and snATACseq for DNA assays, scRNAseq for transcriptomics, and paired protein assays such as multiplexed immunofluorescence …

Modeling Of Cns Cancer With A Focus On The Immune Component, Daniel Zamler

Dissertations & Theses (Open Access)

The knowledge surrounding cancers of the central nervous system remains poorly developed, in particular with regard to the immune component. The works contained in this thesis look at craniopharyngioma, glioblastoma, and several forms of brain metastasis. While some attention is given to the tumor cells themselves, as well as the patient setting which these studies model, the immune component of disease progression and treatment plays a strong role in each and is the primary focus of the works contained.

Craniopharyngioma is a relatively rare tumor in adults. Although histologically benign, it can be locally aggressive and may require additional therapeutic …

Alternative Adenosine Receptor Activation: The Netrin-Adora2b Link., Xiaoyi Yuan, Tingting Mills, Marie-Francoise Doursout, Scott E Evans, Marcos F Vidal Melo, Holger K Eltzschig

Journal Articles

During hypoxia or inflammation, extracellular adenosine levels are elevated. Studies using pharmacologic approaches or genetic animal models pertinent to extracellular adenosine signaling implicate this pathway in attenuating hypoxia-associated inflammation. There are four distinct adenosine receptors. Of these, it is not surprising that the Adora2b adenosine receptor functions as an endogenous feedback loop to control hypoxia-associated inflammation. First, Adora2b activation requires higher adenosine concentrations compared to other adenosine receptors, similar to those achieved during hypoxic inflammation. Second, Adora2b is transcriptionally induced during hypoxia or inflammation by hypoxia-inducible transcription factor HIF1A. Studies seeking an alternative adenosine receptor activation mechanism have linked netrin-1 …

Methodologies To Unlock The Molecular Expression And Cellular Structure Of Ocular Lens Epithelial Cells, Justin Parreno, Grace Emin, Michael P Vu, Jackson T Clark, Sandeep Aryal, Shaili D Patel, Catherine Cheng

Journal Articles

The transparent ocular lens in the anterior chamber of the eye is responsible for fine focusing of light onto the retina. The lens is entirely cellular with bulk of the tissue composed of fiber cells, and the anterior hemisphere of the lens is covered by a monolayer of epithelial cells. Lens epithelial cells are important for maintaining fiber cell homeostasis and for continual growth of the lens tissue throughout life. Cataracts, defined as any opacity in the lens, remain the leading cause of blindness in the world. Following cataract surgery, lens epithelial cells can undergo a process of epithelial-to-mesenchymal transition …

Myeloid Hypoxia-Inducible Factor Hif1a Provides Cardio-Protection During Ischemia And Reperfusion, Ka Lin Heck-Swain, Jiwen Li, Wei Ruan, Xiaoyi Yuan, Yanyu Wang, Michael Koeppen, Holger K Eltzschig

Journal Articles

The transcription factor hypoxia-inducible factor HIF1A induces cardioprotection from ischemia and reperfusion injury. Here, we investigate tissue-specific pathways that are critical for HIF1A-elicited tissue protection. Initial studies showed that mice with induced global Hif1a deletion (Hif1aloxP/loxP UbiquitinCre+) have exaggerated myocardial injury during in situ ischemia and reperfusion. Surprisingly, this phenotype was mirrored only in mice with myeloid-specific Hif1a deletion (Hif1aloxP/loxP LysM Cre+). In contrast, mice with myocardial specific (Hif1aloxP/loxP Myosin Cre+), or vascular Hif1a deletion (Hif1aloxP/loxP VEcadherin Cre+) experienced similar levels of injury as controls. Subsequent studies using adoptive transfer of Hif1a-deficient polymorphonuclear neutrophils (PMNs) …