Biological Phenomena, Cell Phenomena, and Immunity Commons^™

Ezh2 And Endometrial Cancer Development: Insights From A Mouse Model, Xin Fang, Nan Ni, Xiaofang Wang, Yanan Tian, Ivan Ivanov, Monique Rijnkels, Kayla J Bayless, John P Lydon, Qinglei Li

Faculty, Staff and Students Publications

Enhancer of zeste homolog 2 (EZH2), a core component of polycomb repressive complex 2, plays an important role in cancer development. As both oncogenic and tumor suppressive functions of EZH2 have been documented in the literature, the objective of this study is to determine the impact of Ezh2 deletion on the development and progression of endometrial cancer induced by inactivation of phosphatase and tensin homolog (PTEN), a tumor suppressor gene frequently dysregulated in endometrial cancer patients. To this end, we created mice harboring uterine deletion of both Ezh2 and Pten using Cre recombinase driven by the progesterone receptor …

Increased Dna Methylation, Cellular Senescence And Premature Epigenetic Aging In Guinea Pigs And Humans With Tuberculosis, Carly A Bobak, Abhimanyu, Harini Natarajan, Tanmay Gandhi, Sandra L Grimm, Tomoki Nishiguchi, Kent Koster, Santiago Carrero Longlax, Qiniso Dlamini, Jacquiline Kahari, Godwin Mtetwa, Jeffrey D Cirillo, James O'Malley, Jane E Hill, Cristian Coarfa, Andrew R Dinardo

Faculty, Staff and Students Publications

Background: Tuberculosis (TB) is the archetypical chronic infection, with patients having months of symptoms before diagnosis. In the two years after successful therapy, survivors of TB have a three-fold increased risk of death.

Methods: Guinea pigs were infected with Mycobacterium tuberculosis (Mtb) for 45 days, followed by RRBS DNA methylation analysis. In humans, network analysis of differentially expressed genes across three TB cohorts were visualized at the pathway-level. Serum levels of inflammation were measured by ELISA. Horvath (DNA methylation) and RNA-seq biological clocks were used to investigate shifts in chronological age among humans with TB.

Results: Guinea pigs …

Blood–Brain Barrier Disruption Mediated By Ffa1 Receptor—Evidence Using Miniscope, Kristen L Lindenau, Jeffrey L Barr, Christopher R Higgins, Kevin T Sporici, Eugen Brailoiu, Gabriela C Brailoiu

Faculty, Staff and Student Publications

Omega-3 polyunsaturated fatty acids (n-3 PUFAs), obtained from diet and dietary supplements, have been tested in clinical trials for the prevention or treatment of several diseases. n-3 PUFAs exert their effects by activation of free fatty acid (FFA) receptors. FFA1 receptor, expressed in the pancreas and brain, is activated by medium- to long-chain fatty acids. Despite some beneficial effects on cognition, the effects of n-3 PUFAs on the blood-brain barrier (BBB) are not clearly understood. We examined the effects of FFA1 activation on BBB permeability in vitro, using rat brain microvascular endothelial cells (RBMVEC), and in vivo, by assessing Evans …

A Human Breast Cancer-Derived Xenograft And Organoid Platform For Drug Discovery And Precision Oncology, Katrin P Guillen, Maihi Fujita, Andrew J Butterfield, Sandra D Scherer, Matthew H Bailey, Zhengtao Chu, Yoko S Derose, Ling Zhao, Emilio Cortes-Sanchez, Chieh-Hsiang Yang, Jennifer Toner, Guoying Wang, Yi Qiao, Xiaomeng Huang, Jeffery A Greenland, Jeffery M Vahrenkamp, David H Lum, Rachel E Factor, Edward W Nelson, Cindy B Matsen, Jane M Poretta, Regina Rosenthal, Anna C Beck, Saundra S Buys, Christos Vaklavas, John H Ward, Randy L Jensen, Kevin B Jones, Zheqi Li, Steffi Oesterreich, Lacey E Dobrolecki, Satya S Pathi, Xing Yi Woo, Kristofer C Berrett, Mark E Wadsworth, Jeffrey H Chuang, Michael T Lewis, Gabor T Marth, Jason Gertz, Katherine E Varley, Bryan E Welm, Alana L Welm

Faculty, Staff and Students Publications

Microscaled proteogenomics was deployed to probe the molecular basis for differential response to neoadjuvant carboplatin and docetaxel combination chemotherapy for triple-negative breast cancer (TNBC). Proteomic analyses of pretreatment patient biopsies uniquely revealed metabolic pathways, including oxidative phosphorylation, adipogenesis, and fatty acid metabolism, that were associated with resistance. Both proteomics and transcriptomics revealed that sensitivity was marked by elevation of DNA repair, E2F targets, G₂–M checkpoint, interferon-gamma signaling, and immune-checkpoint components. Proteogenomic analyses of somatic copy-number aberrations identified a resistance-associated 19q13.31–33 deletion where LIG1, POLD1, and XRCC1 are located. In orthogonal datasets, LIG1 (DNA ligase I) gene …

Quality Control For Single Cell Imaging Analytics Using Endocrine Disruptor-Induced Changes In Estrogen Receptor Expression, Fabio Stossi, Pankaj K Singh, Ragini M Mistry, Hannah L Johnson, Radhika D Dandekar, Maureen G Mancini, Adam T Szafran, Arvind U Rao, Michael A Mancini

Faculty, Staff and Students Publications

BACKGROUND: Diverse toxicants and mixtures that affect hormone responsive cells [endocrine disrupting chemicals (EDCs)] are highly pervasive in the environment and are directly linked to human disease. They often target the nuclear receptor family of transcription factors modulating their levels and activity. Many high-throughput assays have been developed to query such toxicants; however, single-cell analysis of EDC effects on endogenous receptors has been missing, in part due to the lack of quality control metrics to reproducibly measure cell-to-cell variability in responses.

OBJECTIVE: We began by developing single-cell imaging and informatic workflows to query whether the single cell distribution of the …

K-Ras And P53 Mouse Model With Molecular Characteristics Of Human Rhabdomyosarcoma And Translational Applications, Kengo Nakahata, Brian W Simons, Enrico Pozzo, Ryan Shuck, Lyazat Kurenbekova, Zachary Prudowsky, Kshiti Dholakia, Cristian Coarfa, Tajhal D Patel, Lawrence A Donehower, Jason T Yustein

Faculty, Staff and Students Publications

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children, with overall long-term survival rates of ∼65-70%. Thus, additional molecular insights and representative models are critical for identifying and evaluating new treatment modalities. Using MyoD-Cre-mediated introduction of mutant K-RasG12D and perturbations in p53, we developed a novel genetically engineered mouse model (GEMM) for RMS. The anatomic sites of primary RMS development recapitulated human disease, including tumors in the head, neck, extremities and abdomen. We confirmed RMS histology and diagnosis through Hematoxylin and Eosin staining, and positive immunohistochemical staining for desmin, myogenin, and phosphotungstic acid-Hematoxylin. Cell lines from GEMM tumors …

Isa101 And Nivolumab For Hpv-16+ Cancer: Updated Clinical Efficacy And Immune Correlates Of Response, Luana Guimaraes De Sousa, Kimal Rajapakshe, Jaime Rodriguez Canales, Renee L Chin, Lei Feng, Qi Wang, Tomas Z Barrese, Erminia Massarelli, William William, Faye M Johnson, Renata Ferrarotto, Ignacio Wistuba, Cristian Coarfa, Jack Lee, Jing Wang, Cornelis J M Melief, Michael A Curran, Bonnie S Glisson

Faculty, Staff and Students Publications

BACKGROUND: The combination of ISA101, a human papilloma virus (HPV) 16 peptide vaccine, and nivolumab showed a promising response rate of 33% in patients with incurable HPV-16+ cancer. Here we report long-term clinical outcomes and immune correlates of response.

METHODS: Patients with advanced HPV-16+ cancer and less than two prior regimens for recurrence were enrolled to receive ISA101 (100 µg/peptide) on days 1, 22, and 50 and nivolumab 3 mg/kg every 2 weeks beginning day 8 for up to 1 year. Baseline tumor samples were stained with multiplex immunofluorescence for programmed death-ligand 1 (PD-L1), programmed cell death protein-1 (PD-1), CD3, …

Δnp63 Regulates A Common Landscape Of Enhancer Associated Genes In Non-Small Cell Lung Cancer, Marco Napoli, Sarah J Wu, Bethanie L Gore, Hussein A Abbas, Kyubum Lee, Rahul Checker, Shilpa Dhar, Kimal Rajapakshe, Aik Choon Tan, Min Gyu Lee, Cristian Coarfa, Elsa R Flores

Faculty, Staff and Students Publications

Distinct lung stem cells give rise to lung adenocarcinoma (LUAD) and squamous cell carcinoma (LUSC). ΔNp63, the p53 family member and p63 isoform, guides the maturation of these stem cells through the regulation of their self-renewal and terminal differentiation; however, the underlying mechanistic role regulated by ∆Np63 in lung cancer development has remained elusive. By utilizing a ΔNp63-specific conditional knockout mouse model and xenograft models of LUAD and LUSC, we found that ∆Np63 promotes non-small cell lung cancer by maintaining the lung stem cells necessary for lung cancer cell initiation and progression in quiescence. ChIP-seq analysis of lung basal cells, …

Characterization Of The Copd Alveolar Niche Using Single-Cell Rna Sequencing, Maor Sauler, John E Mcdonough, Taylor S Adams, Neeharika Kothapalli, Thomas Barnthaler, Rhiannon B Werder, Jonas C Schupp, Jessica Nouws, Matthew J Robertson, Cristian Coarfa, Tao Yang, Maurizio Chioccioli, Norihito Omote, Carlos Cosme, Sergio Poli, Ehab A Ayaub, Sarah G Chu, Klaus H Jensen, Jose L Gomez, Clemente J Britto, Micha Sam B Raredon, Laura E Niklason, Andrew A Wilson, Pascal N Timshel, Naftali Kaminski, Ivan O Rosas

Faculty, Staff and Students Publications

Chronic obstructive pulmonary disease (COPD) is a leading cause of death worldwide, however our understanding of cell specific mechanisms underlying COPD pathobiology remains incomplete. Here, we analyze single-cell RNA sequencing profiles of explanted lung tissue from subjects with advanced COPD or control lungs, and we validate findings using single-cell RNA sequencing of lungs from mice exposed to 10 months of cigarette smoke, RNA sequencing of isolated human alveolar epithelial cells, functional in vitro models, and in situ hybridization and immunostaining of human lung tissue samples. We identify a subpopulation of alveolar epithelial type II cells with transcriptional evidence for aberrant …

Rspo2 And Rankl Signal Through Lgr4 To Regulate Osteoclastic Premetastatic Niche Formation And Bone Metastasis, Zhiying Yue, Xin Niu, Zengjin Yuan, Qin Qin, Wenhao Jiang, Liang He, Jingduo Gao, Yi Ding, Yanxi Liu, Ziwei Xu, Zhenxi Li, Zhengfeng Yang, Rong Li, Xiwen Xue, Yankun Gao, Fei Yue, Xiang H-F Zhang, Guohong Hu, Yi Wang, Yi Li, Geng Chen, Stefan Siwko, Alison Gartland, Ning Wang, Jianru Xiao, Mingyao Liu, Jian Luo

Faculty, Staff and Students Publications

Therapeutics targeting osteoclasts are commonly used treatments for bone metastasis; however, whether and how osteoclasts regulate premetastatic niche and bone tropism are largely unknown. In this study, we report that osteoclast precursors (OPs) can function as a premetastatic niche component that facilitates breast cancer (BCa) bone metastasis at early stages. At the molecular level, unbiased GPCR ligand/agonist screening in BCa cells suggested that R-spondin 2 (RSPO2) and RANKL, through interaction with their receptor LGR4, promoted osteoclastic premetastatic niche formation and enhanced BCa bone metastasis. This was achieved by RSPO2/RANKL-LGR4 signal modulating the WNT inhibitor DKK1 through Gαq and β-catenin signaling. …

Embryonic Hypotaurine Levels Contribute To Strain-Dependent Susceptibility In Mouse Models Of Valproate-Induced Neural Tube Defects, John W Steele, Ying Linda Lin, Nellie Chen, Bogdan J Wlodarczyk, Qiuying Chen, Nabeel Attarwala, Madhu Venkatesalu, Robert M Cabrera, Steven S Gross, Richard H Finnell

Faculty, Staff and Students Publications

Valproic acid (VPA, valproate, Depakote) is a commonly used anti-seizure medication (ASM) in the treatment of epilepsy and a variety of other neurological disorders. While VPA and other ASMs are efficacious for management of seizures, they also increase the risk for adverse pregnancy outcomes, including neural tube defects (NTDs). Thus, the utility of these drugs during pregnancy and in women of childbearing potential presents a continuing public health challenge. Elucidating the underlying genetic or metabolic risk factors for VPA-affected pregnancies may lead to development of non-teratogenic ASMs, novel prevention strategies, or more targeted methods for managing epileptic pregnancies. To address …

Endometriosis-Associated Angiogenesis And Anti-Angiogenic Therapy For Endometriosis, Monica S Chung, Sang Jun Han

Faculty, Staff and Students Publications

Endometriosis is a known estrogen-dependent inflammatory disease affecting reproductive-aged women. Common symptoms include pelvic pain, dysmenorrhea, dyspareunia, heavy menstrual bleeding, and infertility. The exact etiology of endometriosis is largely unknown, and, thus, the diagnosis and treatment of endometriosis are challenging. A complex interplay of many molecular mechanisms is thought to aid in the progression of endometriosis, most notably angiogenesis. This mini-review examines our current knowledge of the molecular etiology of endometriosis-associated angiogenesis and discusses anti-angiogenic therapy, in the blockade of endometriosis-associated angiogenesis, as potential non-hormonal therapy for the treatment of endometriosis.

Common Genomic Aberrations In Mouse And Human Breast Cancers With Concurrent P53 Deficiency And Activated Pten-Pi3k-Akt Pathway, Jarrod D Martinez, Qianxing Mo, Yixiang Xu, Li Qin, Yi Li, Jianming Xu

Faculty, Staff and Students Publications

Simultaneous P53 loss and activation of the PTEN-restricted PI3K-AKT pathway frequently occur in aggressive breast cancers. P53 loss causes genome instability, while PTEN loss and/or activating mutations of PIK3CA and AKT promote cancer cell proliferation that also increases incidences of genomic aberrations. However, the genomic alterations associated with P53 loss and activated PTEN-PI3K-AKT signaling in breast cancer have not been defined. Spatiotemporally controlled breast cancer models with inactivation of both P53 and Pten in adult mice have not been established for studying genomic alterations. Herein, we deleted both floxed Pten and Tp53 genes in the mammary gland epithelial cells in …

Targeting The Pro-Survival Protein Bcl-2 To Prevent Breast Cancer, Adelaide Young, Wen Bu, Weiyu Jiang, Amy Ku, Jyoti Kapali, Sagar Dhamne, Lan Qin, Susan G Hilsenbeck, Yi-Chieh Nancy Du, Yi Li

Faculty, Staff and Students Publications

Current chemopreventive strategies require 3-5 years of continuous treatment and have the concerns of significant side effects; therefore, new chemopreventive agents that require shorter and safer treatments are urgently needed. In this study, we developed a new murine model of breast cancer that mimics human breast cancer initiation and is ideal for testing the efficacy of chemopreventive therapeutics. In this model, introduction of lentivirus carrying a PIK3CA gene mutant commonly found in breast cancers infects a small number of the mammary cells, leading to atypia first and then to ductal carcinomas that are positive for both estrogen receptor and progesterone …

Decidualization Of Human Endometrial Stromal Cells Requires Steroid Receptor Coactivator-3, Vineet K Maurya, Maria M Szwarc, David M Lonard, William E Gibbons, San-Pin Wu, Bert W O'Malley, Francesco J Demayo, John P Lydon

Faculty, Staff and Students Publications

Steroid receptor coactivator-3 (SRC-3; also known as NCOA3 or AIB1) is a member of the multifunctional p160/SRC family of coactivators, which also includes SRC-1 and SRC-2. Clinical and cell-based studies as well as investigations on mice have demonstrated pivotal roles for each SRC in numerous physiological and pathophysiological contexts, underscoring their functional pleiotropy. We previously demonstrated the critical involvement of SRC-2 in murine embryo implantation as well as in human endometrial stromal cell (HESC) decidualization, a cellular transformation process required for trophoblast invasion and ultimately placentation. We show here that, like SRC-2, SRC-3 is expressed in the epithelial and stromal …

Nuclear Progesterone Receptor Expressed By The Cortical Thymic Epithelial Cells Dictates Thymus Involution In Murine Pregnancy, Soo Hyun Ahn, Sean L Nguyen, Tae Hoon Kim, Jae-Wook Jeong, Ripla Arora, John P Lydon, Margaret G Petroff

Faculty, Staff and Students Publications

Progesterone is a gonadal pro-gestational hormone that is absolutely necessary for the success of pregnancy. Most notable actions of progesterone are observed in the female reproductive organs, the uterus and the ovary. Acting through the nuclear progesterone receptor (PGR), progesterone prepares the endometrium for implantation of the embryo. Interestingly, the maternal thymus also is a known expressor of Pgr; its absence is associated with murine pregnancy complications. However, the localization of its expression and its functional importance were not known. Here, we used a transgenic dual fluorescent reporter mouse model and genetic deletion of Pgr in Foxn1+ thymic epithelial …

Gut Microbiota From Sjögren Syndrome Patients Causes Decreased T Regulatory Cells In The Lymphoid Organs And Desiccation-Induced Corneal Barrier Disruption In Mice, Laura Schaefer, Claudia M Trujillo-Vargas, Firas S Midani, Stephen C Pflugfelder, Robert A Britton, Cintia S De Paiva

Faculty, Staff and Students Publications

Sjögren syndrome (SS) is an autoimmune inflammatory disorder characterized by secretory dysfunction in the eye and mouth; in the eye, this results in tear film instability, reduced tear production, and corneal barrier disruption. A growing number of studies show that homeostasis of the ocular surface is impacted by the intestinal microbiome, and several 16S sequencing studies have demonstrated dysbiosis of the intestinal microbiota in SS patients. In this study, we utilized metagenomic sequencing to perform a deeper analysis of the intestinal microbiome using stools collected from sex- and age-matched healthy (n = 20), dry eye (n = 4) …

Clonal Hematopoiesis Analyses In Clinical, Epidemiologic, And Genetic Aging Studies To Unravel Underlying Mechanisms Of Age-Related Dysfunction In Humans, Kenneth Walsh, Nalini Raghavachari, Candace Kerr, Alexander G Bick, Steven R Cummings, Todd Druley, Cynthia E Dunbar, Giulio Genovese, Margaret A Goodell, Siddhartha Jaiswal, Jaroslaw Maciejewski, Pradeep Natarajan, Anastasia V Shindyapina, Alan R Shuldiner, Erik B Van Den Akker, Jan Vijg

Faculty, Staff and Students Publications

Aging is characterized by increased mortality, functional decline, and exponential increases in the incidence of diseases such as cancer, stroke, cardiovascular disease, neurological disease, respiratory disease, etc. Though the role of aging in these diseases is widely accepted and considered to be a common denominator, the underlying mechanisms are largely unknown. A significant age-related feature observed in many population cohorts is somatic mosaicism, the detectable accumulation of somatic mutations in multiple cell types and tissues, particularly those with high rates of cell turnover (e.g., skin, liver, and hematopoietic cells). Somatic mosaicism can lead to the development of cellular clones that …

Identification Of Serum Mirna Signature And Establishment Of A Nomogram For Risk Stratification In Patients With Pancreatic Ductal Adenocarcinoma, Raju Kandimalla, Tadanobu Shimura, Saurav Mallik, Fuminori Sonohara, Susan Tsai, Douglas B Evans, Song Cheol Kim, Hideo Baba, Yasuhiro Kodera, Daniel Von Hoff, Xi Chen, Ajay Goel

Faculty, Staff and Students Publications

OBJECTIVE: The aim of the study was to perform mRNA-miRNA regulatory network analyses to identify a miRNA panel for molecular subtype identification and stratification of high-risk patients with pancreatic ductal adenocarcinoma (PDAC).

BACKGROUND: Recent transcriptional profiling effort in PDAC has led to the identification of molecular subtypes that associate with poor survival; however, their clinical significance for risk stratification in patients with PDAC has been challenging.

METHODS: By performing a systematic analysis in The Cancer Genome Atlas and International Cancer Genome Consortium cohorts, we discovered a panel of miRNAs that associated with squamous and other poor molecular subtypes in PDAC. …

Modified Vaccinia Ankara Expressing Eehv1a Glycoprotein B Elicits Humoral And Cell-Mediated Immune Responses In Mice, Taylor Pursell, Jennifer L Spencer Clinton, Jie Tan, Rongsheng Peng, Paul D Ling

Faculty, Staff and Students Publications

Elephant endotheliotropic herpesvirus (EEHV) can cause lethal hemorrhagic disease (EEHV-HD) in Asian elephants and is the largest cause of death in captive juvenile Asian elephants in North America and Europe. EEHV-HD also has been documented in captive and wild elephants in their natural range countries. A safe and effective vaccine to prevent lethal EEHV infection would significantly improve conservation efforts for this endangered species. Recent studies from our laboratory suggest that EEHV morbidity and mortality are often associated with primary infection. Therefore, we aim to generate a vaccine, particularly for EEHV1 naïve animals, with the goal of preventing lethal EEHV-HD. …

Hypermethylation Of Pi3k-Akt Signalling Pathway Genes Is Associated With Human Neural Tube Defects, Tian Tian, Xinyuan Lai, Kuanhui Xiang, Xiao Han, Shengju Yin, Robert M Cabrera, John W Steele, Yunping Lei, Xuanye Cao, Richard H Finnell, Linlin Wang, Aiguo Ren

Faculty, Staff and Students Publications

Neural tube defects (NTDs) are a group of common and severe congenital malformations. The PI3K-AKT signalling pathway plays a crucial role in the neural tube development. There is limited evidence concerning any possible association between aberrant methylation in PI3K-AKT signalling pathway genes and NTDs. Therefore, we aimed to investigate potential associations between aberrant methylation of PI3K-AKT pathway genes and NTDs. Methylation studies of PI3K-AKT pathway genes utilizing microarray genome-methylation data derived from neural tissues of ten NTD cases and eight non-malformed controls were performed. Targeted DNA methylation analysis was subsequently performed in an independent cohort of 73 NTD cases and …

Advancing Rna Virus Discovery And Biology With Whole Genome Sequencing, Mariah Katherine Taylor

Theses and Dissertations (ETD)

Two RNA virus families that pose a threat to human and animal health are Hantaviridae and Coronaviridae. These RNA viruses which originate in wildlife continue and will continue to cause disease, and hence, it is critical that scientific research define the mechanisms as to how these viruses spillover and adapt to new hosts to become endemic. One gap in our ability to define these mechanisms is the lack of whole genome sequences for many of these viruses. To address this specific gap, I developed a versatile amplicon-based whole-genome sequencing (WGS) approach to identify viral genomes of hantaviruses and severe acute …

Habitual Sleep Duration And The Colonic Mucosa-Associated Gut Microbiota In Humans-A Pilot Study, Ritwick Agrawal, Nadim J Ajami, Sonal Malhotra, Liang Chen, Donna L White, Amir Sharafkhaneh, Kristi L Hoffman, David Y Graham, Hashem B El-Serag, Joseph F Petrosino, Li Jiao

Faculty, Staff and Students Publications

We examined the association between the colonic adherent microbiota and nocturnal sleep duration in humans. In a cross-sectional study, 63 polyp-free adults underwent a colonoscopy and donated 206 mucosal biopsies. The gut microbiota was profiled using the 16S rRNA gene sequencing targeting the V4 region. The sequence reads were processed using UPARSE and DADA2, respectively. Lifestyle factors, including sleep habits, were obtained using an interviewer-administered questionnaire. We categorized the participants into short sleepers (<6 h per night; n = 16) and normal sleepers (6–8 h per night; n = 47) based on self-reported data. Differences in bacterial biodiversity and the taxonomic relative abundance …

Identification Of Effectors Of Synergistic Lethality In Candida Albicans-Staphylococcus Aureus Polymicrobial Intra-Abdominal Infection, Olivia Adele Todd

Theses and Dissertations (ETD)

Candida albicans, an opportunistic fungal pathogen, and Staphylococcus aureus, a ubiquitous pathogenic bacterium, are among the most prevalent causes of nosocomial infections and cause severe morbidity and mortality. Moreover, they are frequently coisolated from central venous catheters and deep-seated infections, including intra-abdominal sepsis. Relatively little is known about the complex interactions and signaling events that occur between microbes and even less so how microbial “cross-talk” shapes human health and disease.

Using a murine model of polymicrobial intra-abdominal infection (IAI), we have previously shown that coinfection with C. albicans and S. aureus leads to synergistic lethality whereas monomicrobial infection is nonlethal. …

Developing A Microdialysis Sampling-Based Biofilm/Macrophage Co-Culture Model, Alda Diaz Perez

Graduate Theses and Dissertations

The host immune system and bacterial cells are known to interact during the human lifetime. Bacteria secrete a wide variety of signaling molecules, known as quorum sensing (QSC) molecules, that modulate the host immune system. While immune-biofilm interactions involve this chemical signaling network, the mechanisms through which this occurs are not well understood. This work aimed to develop a new method that can be used not only in vitro settings but also in vivo. The microdialysis sampling technique has widely been used in in vitro and in vivo settings in humans, mice, and rats for the collection of neuropeptides, cytokines, …

Delineating The Upc2a Regulon In Candida Glabrata, Yu Li

Theses and Dissertations (ETD)

Candida glabrata is the second most common cause of invasive candidiasis. Intrinsic resistance has greatly limited the utility of the triazole antifungal, fluconazole, in the treatment of invasive fungal infection. The transcription factor Upc2 regulates the expression of sterol biosynthesis genes in yeast. Disrupting UPC2A in C. glabrata greatly increases its susceptibility to fluconazole (FLU) in both FLU-susceptible and -resistant clinical isolates. Therefore, the Upc2A and its target genes represent a potential pathway for overcoming FLU resistance in C. glabrata. We aimed to delineate the Upc2A regulon to determine its target genes involved in FLU resistance. Transcriptome sequencing (RNA-seq) analysis …

Trypanosoma Cruzi Modulates Piwi-Interacting Rna Expression In Primary Human Cardiac Myocytes During The Early Phase Of Infection, Kayla J. Rayford, Ayorinde Cooley, Ashutosh Arun, Girish Rachakonda, Yulia Kleschenko, Fernando Villalta, Siddharth Pratap, Maria F. Lima, Pius N. Nde

Publications and Research

Trypanosoma cruzi dysregulates the gene expression profile of primary human cardiomyocytes (PHCM) during the early phase of infection through a mechanism which remains to be elucidated. The role that small non-coding RNAs (sncRNA) including PIWI-interacting RNA (piRNA) play in regulating gene expression during the early phase of infection is unknown. To understand how T. cruzi dysregulate gene expression in the heart, we challenged PHCM with T. cruzi trypomastigotes and analyzed sncRNA, especially piRNA, by RNA-sequencing. The parasite induced significant differential expression of host piRNAs, which can target and regulate the genes which are important during the early infection phase. An …

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 …

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 …

Thrombospondin-1 Plays An Essential Role In Yes-Associated Protein Nuclear Translocation During The Early Phase Of Trypanosoma Cruzi Infection In Heart Endothelial Cells, Ashutosh Arun, Kayla J. Rayford, Ayorinde Cooley, Girish Rachakonda, Fernando Villalta, Siddharth Pratap, Maria F. Lima, Nader Sheibani, Pius N. Nde

Publications and Research

The protozoan parasite Trypanosoma cruzi is the causative agent of Chagas disease. This neglected tropical disease causes severe morbidity and mortality in endemic regions. About 30% of T. cruzi infected individuals will present with cardiac complications. Invasive trypomastigotes released from infected cells can be carried in the vascular endothelial system to infect neighboring and distant cells. During the process of cellular infection, the parasite induces host cells, to increase the levels of host thrombospondin-1 (TSP-1), to facilitate the process of infection. TSP-1 plays important roles in the functioning of vascular cells, including vascular endothelial cells with important implications in cardiovascular …