Medical Microbiology Commons^™

Optimization Of The Antifungal Properties Of The Bacterial Peptide Entv By Variant Analysis, Shantanu Guha, Shane A Cristy, Giuseppe Buda De Cesare, Melissa R Cruz, Michael C Lorenz, Danielle A Garsin

Faculty, Staff and Student Publications

Fungal resistance to commonly used medicines is a growing public health threat, and there is a dire need to develop new classes of antifungals. We previously described a peptide produced by Enterococcus faecalis, EntV, that restricts Candida albicans to a benign form rather than having direct fungicidal activity. Moreover, we showed that one 12-amino acid (aa) alpha helix of this peptide retained full activity, with partial activity down to the 10aa alpha helix. Using these peptides as a starting point, the current investigation sought to identify the critical features necessary for antifungal activity and to screen for new variants …

Progress Toward A Vaccine For Extraintestinal Pathogenic Coli (Expec) Ii: Efficacy Of A Toxin-Autotransporter Dual Antigen Approach, Yikun Xing, Justin R Clark, James D Chang, Jacob J Zulk, Dylan M Chirman, Felipe-Andres Piedra, Ellen E Vaughan, Haroldo J Hernandez Santos, Kathryn A Patras, Anthony W Maresso

Faculty, Staff and Students Publications

Extraintestinal pathogenic Escherichia coli (ExPEC) is a leading cause of worldwide morbidity and mortality, the top cause of antimicrobial-resistant (AMR) infections, and the most frequent cause of life-threatening sepsis and urinary tract infections (UTI) in adults. The development of an effective and universal vaccine is complicated by this pathogen’s pan-genome, its ability to mix and match virulence factors and AMR genes via horizontal gene transfer, an inability to decipher commensal from pathogens, and its intimate association and co-evolution with mammals. Using a pan virulome analysis of >20,000 sequenced E. coli strains, we identified the secreted cytolysin α-hemolysin (HlyA) as a …

Autologous Bone Marrow Mononuclear Cells To Treat Severe Traumatic Brain Injury In Children, Charles S Cox, David M Notrica, Jenifer Juranek, Jeffrey H Miller, Fabio Triolo, Steven Kosmach, Sean I Savitz, P David Adelson, Claudia Pedroza, Scott D Olson, Michael C Scott, Akshita Kumar, Benjamin M Aertker, Henry W Caplan, Margaret L Jackson, Brijesh S Gill, Robert A Hetz, Michael S Lavoie, Linda Ewing-Cobbs

Faculty, Staff and Student Publications

Autologous bone marrow mononuclear cells (BMMNCs) infused after severe traumatic brain injury have shown promise for treating the injury. We evaluated their impact in children, particularly their hypothesized ability to preserve the blood–brain barrier and diminish neuroinflammation, leading to structural CNS preservation with improved outcomes.

We performed a randomized, double-blind, placebo-sham-controlled Bayesian dose-escalation clinical trial at two children's hospitals in Houston, TX and Phoenix, AZ, USA (NCT01851083). Patients 5–17 years of age with severe traumatic brain injury (Glasgow Coma Scale score ≤ 8) were randomized to BMMNC or placebo (3:2). Bone marrow harvest, cell isolation and infusion were …

Sialic Acid-Siglec-E Interactions Regulate The Response Of Neonatal Macrophages To Group B Streptococcus, Sean J Lund, Pamela G B Del Rosario, Asami Honda, Kaitlin J Caoili, Marten A Hoeksema, Victor Nizet, Kathryn A Patras, Lawrence S Prince

Faculty, Staff and Students Publications

The mammalian Siglec receptor sialoadhesin (Siglec1, CD169) confers innate immunity against the encapsulated pathogen group B Streptococcus (GBS). Newborn lung macrophages have lower expression levels of sialoadhesin at birth compared with the postnatal period, increasing their susceptibility to GBS infection. In this study, we investigate the mechanisms regulating sialoadhesin expression in the newborn mouse lung. In both neonatal and adult mice, GBS lung infection reduced Siglec1 expression, potentially delaying acquisition of immunity in neonates. Suppression of Siglec1 expression required interactions between sialic acid on the GBS capsule and the inhibitory host receptor Siglec-E. The Siglec1 gene contains multiple STAT binding …

Quorum-Sensing Agr System Of Staphylococcus Aureus Primes Gene Expression For Protection From Lethal Oxidative Stress, Magdalena Podkowik, Andrew I Perault, Gregory Putzel, Andrew Pountain, Jisun Kim, Ashley L Dumont, Erin E Zwack, Robert J Ulrich, Theodora K Karagounis, Chunyi Zhou, Andreas F Haag, Julia Shenderovich, Gregory A Wasserman, Junbeom Kwon, John Chen, Anthony R Richardson, Jeffrey N Weiser, Carla R Nowosad, Desmond S Lun, Dane Parker, Alejandro Pironti, Xilin Zhao, Karl Drlica, Itai Yanai, Victor J Torres, Bo Shopsin

Faculty, Staff and Student Publications

The agr quorum-sensing system links Staphylococcus aureus metabolism to virulence, in part by increasing bacterial survival during exposure to lethal concentrations of H2O2, a crucial host defense against S. aureus. We now report that protection by agr surprisingly extends beyond post-exponential growth to the exit from stationary phase when the agr system is no longer turned on. Thus, agr can be considered a constitutive protective factor. Deletion of agr resulted in decreased ATP levels and growth, despite increased rates of respiration or fermentation at appropriate oxygen tensions, suggesting that Δagr cells undergo a shift towards a hyperactive metabolic …

Histone Proteoform Analysis Reveals Epigenetic Changes In Adult Mouse Brown Adipose Tissue In Response To Cold Stress, Bethany C Taylor, Loic H Steinthal, Michelle Dias, Hari Krishna Yalamanchili, Scott A Ochsner, Gladys E Zapata, Nitesh R Mehta, Neil J Mckenna, Nicolas L Young, Alli M Nuotio-Antar

Faculty, Staff and Students Publications

BACKGROUND: Regulation of the thermogenic response by brown adipose tissue (BAT) is an important component of energy homeostasis with implications for the treatment of obesity and diabetes. Our preliminary analyses of RNA-Seq data uncovered many nodes representing epigenetic modifiers that are altered in BAT in response to chronic thermogenic activation. Thus, we hypothesized that chronic thermogenic activation broadly alters epigenetic modifications of DNA and histones in BAT.

RESULTS: Motivated to understand how BAT function is regulated epigenetically, we developed a novel method for the first-ever unbiased top-down proteomic quantitation of histone modifications in BAT and validated our results with a …

Targeted Deletion Of Nr2f2 And Vcam1 In Theca Cells Impacts Ovarian Follicular Development: Insights Into Polycystic Ovary Syndrome?†, Nicholes R Candelaria, Joanne S Richards

Faculty, Staff and Students Publications

Defining features of polycystic ovary syndrome (PCOS) include elevated expression of steroidogenic genes, theca cell androgen biosynthesis, and peripheral levels of androgens. In previous studies, we identified vascular cell adhesion molecule 1 (VCAM1) as a selective androgen target gene in specific NR2F2/SF1 (+/+) theca cells. By deleting NR2F2 and VCAM1 selectively in CYP17A1 theca cells in mice, we documented that NR2F2 and VCAM1 impact distinct and sometimes opposing theca cell functions that alter ovarian follicular development in vivo: including major changes in ovarian morphology, steroidogenesis, gene expression profiles, immunolocalization images (NR5A1, CYP11A1, NOTCH1, CYP17A1, INSL3, VCAM1, NR2F2) as well as …

Establishment Of Murine Pregnancy Requires The Promyelocytic Leukemia Zinc Finger Transcription Factor, Lan Hai, Vineet K Maurya, Francesco J Demayo, John P Lydon

Faculty, Staff and Students Publications

Using an established human primary cell culture model, we previously demonstrated that the promyelocytic leukemia zinc finger (PLZF) transcription factor is a direct target of the progesterone receptor (PGR) and is essential for progestin-dependent decidualization of human endometrial stromal cells (HESCs). These in vitro findings were supported by immunohistochemical analysis of human endometrial tissue biopsies, which showed that the strongest immunoreactivity for endometrial PLZF is detected during the progesterone (P4)-dominant secretory phase of the menstrual cycle. While these human studies provided critical clinical support for the important role of PLZF in P4-dependent HESC decidualization, functional validation in vivo was not …

Hippo Cooperates With P53 To Maintain Foregut Homeostasis And Suppress The Malignant Transformation Of Foregut Basal Progenitor Cells, Yu Jiang, Haidi Huang, Jiangying Liu, Dan Luo, Rongzi Mu, Jianghong Yuan, Jihong Lin, Qiyue Chen, Wufan Tao, Ling Yang, Man Zhang, Pingping Zhang, Fengqin Fang, Jianming Xu, Qingqiu Gong, Zhiping Xie, Yongchun Zhang

Faculty, Staff and Students Publications

Basal progenitor cells serve as a stem cell pool to maintain the homeostasis of the epithelium of the foregut, including the esophagus and the forestomach. Aberrant genetic regulation in these cells can lead to carcinogenesis, such as squamous cell carcinoma (SCC). However, the underlying molecular mechanisms regulating the function of basal progenitor cells remain largely unknown. Here, we use mouse models to reveal that Hippo signaling is required for maintaining the homeostasis of the foregut epithelium and cooperates with p53 to repress the initiation of foregut SCC. Deletion of

Adipose Triglyceride Lipase Is A Therapeutic Target In Advanced Prostate Cancer That Promotes Metabolic Plasticity, Dominik Awad, Pham Hong Anh Cao, Thomas L Pulliam, Meredith Spradlin, Elavarasan Subramani, Tristen V Tellman, Caroline F Ribeiro, Riccardo Muzzioli, Brittany E Jewell, Hubert Pakula, Jeffrey J Ackroyd, Mollianne M Murray, Jenny J Han, Mei Leng, Antrix Jain, Badrajee Piyarathna, Jingjing Liu, Xingzhi Song, Jianhua Zhang, Albert R Klekers, Justin M Drake, Michael M Ittmann, Cristian Coarfa, David Piwnica-Worms, Mary C Farach-Carson, Massimo Loda, Livia S Eberlin, Daniel E Frigo

Faculty, Staff and Students Publications

UNLABELLED: Lipid metabolism plays a central role in prostate cancer. To date, the major focus has centered on de novo lipogenesis and lipid uptake in prostate cancer, but inhibitors of these processes have not benefited patients. A better understanding of how cancer cells access lipids once they are created or taken up and stored could uncover more effective strategies to perturb lipid metabolism and treat patients. Here, we identified that expression of adipose triglyceride lipase (ATGL), an enzyme that controls lipid droplet homeostasis and a previously suspected tumor suppressor, correlates with worse overall survival in men with advanced, castration-resistant prostate …

Autophagy Differentially Regulates Tissue Tolerance Of Distinct Target Organs In Graft-Versus-Host Disease Models, Katherine Oravecz-Wilson, Emma Lauder, Austin Taylor, Laure Maneix, Jeanine L Van Nostrand, Yaping Sun, Lu Li, Dongchang Zhao, Chen Liu, Pavan Reddy

Faculty, Staff and Students Publications

Tissue-intrinsic mechanisms that regulate severity of systemic pathogenic immune-mediated diseases, such as acute graft-versus-host disease (GVHD), remain poorly understood. Following allogeneic hematopoietic stem cell transplantation, autophagy, a cellular stress protective response, is induced in host nonhematopoietic cells. To systematically address the role of autophagy in various host nonhematopoietic tissues, both specific classical target organs of acute GVHD (intestines, liver, and skin) and organs conventionally not known to be targets of GVHD (kidneys and heart), we generated mice with organ-specific knockout of autophagy related 5 (ATG5) to specifically and exclusively inhibit autophagy in the specific organs. When compared with wild-type recipients, …

Granulocytic Myeloid-Derived Suppressor Cell Activity During Biofilm Infection Is Regulated By A Glycolysis/Hif1a Axis, Christopher M. Horn, Prabhakar Arumugam, Zachary Van Roy, Cortney E. Heim, Rachel W. Fallet, Blake P. Bertrand, Dhananjay Shinde, Vinai Chittezham Thomas, Svetlana Romanova, Tatiana K. Bronich, Curtis Hartman, Kevin Garvin, Tammy Kielian

Journal Articles: Pathology and Microbiology

Staphylococcus aureus is a leading cause of biofilm-associated prosthetic joint infection (PJI). A primary contributor to infection chronicity is an expansion of granulocytic myeloid-derived suppressor cells (G-MDSCs), which are critical for orchestrating the antiinflammatory biofilm milieu. Single-cell sequencing and bioinformatic metabolic algorithms were used to explore the link between G-MDSC metabolism and S. aureus PJI outcome. Glycolysis and the hypoxia response through HIF1a were significantly enriched in G-MDSCs. Interfering with both pathways in vivo, using a 2-deoxyglucose nanopreparation and granulocyte-targeted Hif1a conditional KO mice, respectively, attenuated G-MDSC-mediated immunosuppression and reduced bacterial burden in a mouse model of S. aureus PJI. …

Mutant P53 Protects Triple-Negative Breast Adenocarcinomas From Ferroptosis In Vivo, Denada Dibra, Shunbin Xiong, Sydney M Moyer, Adel K El-Naggar, Yuan Qi, Xiaoping Su, Elisabeth K Kong, Anil Korkut, Guillermina Lozano

Faculty, Staff and Student Publications

The TP53 tumor suppressor gene is mutated early in most of the patients with triple-negative breast cancer (TNBC). The most frequent TP53 alterations are missense mutations that contribute to tumor aggressiveness. Here, we used an autochthonous somatic TNBC mouse model, in which mutant p53 can be toggled on and off genetically while leaving the tumor microenvironment intact and wild-type for p53 to identify physiological dependencies on mutant p53. In TNBCs that develop in this model, deletion of two different hotspot p53R172H and p53R245W mutants triggers ferroptosis in vivo, a cell death mechanism involving iron-dependent lipid peroxidation. Mutant p53 protects cells …

Genome-Wide P63-Target Gene Analyses Reveal Tap63/Nrf2-Dependent Oxidative Stress Responses, Marco Napoli, Avani A Deshpande, Deepavali Chakravarti, Kimal Rajapakshe, Preethi H Gunaratne, Cristian Coarfa, Elsa R Flores

Faculty, Staff and Students Publications

The p53 family member TP63 encodes two sets of N-terminal isoforms, TAp63 and ΔNp63 isoforms. They each regulate diverse biological functions in epidermal morphogenesis and in cancer. In the skin, where their activities have been extensively characterized, TAp63 prevents premature aging by regulating the quiescence and genomic stability of stem cells required for wound healing and hair regeneration, while ΔNp63 controls maintenance and terminal differentiation of epidermal basal cells. This functional diversity is surprising given that these isoforms share a high degree of similarity, including an identical sequence for a DNA-binding domain. To understand the mechanisms of the transcriptional programs …

Gut Epithelial Interleukin-17 Receptor A Signaling Can Modulate Distant Tumors Growth Through Microbial Regulation, Vidhi Chandra, Le Li, Olivereen Le Roux, Yu Zhang, Rian M Howell, Dhwani N Rupani, Seyda Baydogan, Haiyan D Miller, Erick Riquelme, Joseph Petrosino, Michael P Kim, Krishna P L Bhat, James R White, Jay K Kolls, Yuliya Pylayeva-Gupta, Florencia Mcallister

Faculty, Staff and Student Publications

Microbes influence cancer initiation, progression and therapy responsiveness. IL-17 signaling contributes to gut barrier immunity by regulating microbes but also drives tumor growth. A knowledge gap remains regarding the influence of enteric IL-17-IL-17RA signaling and their microbial regulation on the behavior of distant tumors. We demonstrate that gut dysbiosis induced by systemic or gut epithelial deletion of IL-17RA induces growth of pancreatic and brain tumors due to excessive development of Th17, primary source of IL-17 in human and mouse pancreatic ductal adenocarcinoma, as well as B cells that circulate to distant tumors. Microbial dependent IL-17 signaling increases DUOX2 signaling in …

C1q Is Elevated During Chronic Staphylococcus Epidermidis Central Nervous System Catheter Infection, Matthew K. Beaver, Lara Bergdolt, Anna Dunaevsky, Tammy Kielian, Gwenn Skar

Journal Articles: Pathology and Microbiology

INTRODUCTION: Significant neurologic morbidity is caused by pediatric cerebrospinal fluid (CSF) shunt infections. The underlying mechanisms leading to impaired school performance and increased risk of seizures are unknown, however, a better understanding of these mechanisms may allow us to temper their consequences. Recent evidence has demonstrated important roles for complement proteins in neurodevelopment and neuroinflammation.

METHODS: We examined complement activation throughout

RESULTS: We found that MASP2 predominated early in catheter infection, but that Factor B was elevated at intermediate time points. Unexpectedly C1q was elevated at late timepoints when bacterial burdens were low or undetectable. Based on these findings and …

Aconitate Decarboxylase 1 Mediates The Acute Airway Inflammatory Response To Environmental Exposures, Aaron Schwab, Amy J. Nelson, Angela Gleason, Oliver Schanze, Todd A. Wyatt, Dhananjay Shinde, Peng Xiao, Vinai Chittezham Thomas, Chittibabu Guda, Kristina L. Bailey, Tammy Kielian, Geoffrey M. Thiele, Jill A. Poole

Journal Articles: Pathology and Microbiology

Background: Environmental lipopolysaccharide (LPS) and microbial component-enriched organic dusts cause significant lung disease. These environmental exposures induce the recruitment and activation of distinct lung monocyte/macrophage subpopulations involved in disease pathogenesis. Aconitate decarboxylase 1 (Acod1) was one of the most upregulated genes following LPS (vs. saline)exposure of murine whole lungs with transcriptomic profiling of sorted lung monocyte/macrophage subpopulations also highlighting its significance. Given monocyte/macrophage activation can be tightly linked to metabolism, the objective of these studies was to determine the role of the immunometabolic regulator ACOD1 inenvironmentalexposure-induced lung inflammation.

Methods: Wild-type (WT) mice were intratracheally (i.t.) instilled with 10 …

Folate Regulation Of Planar Cell Polarity Pathway And F-Actin Through Folate Receptor Alpha, Xiao Han, Xuanye Cao, Robert M Cabrera, Paula Andrea Pimienta Ramirez, Ying Linda Lin, Bogdan J Wlodarczyk, Cuilian Zhang, Richard H Finnell, Yunping Lei

Faculty, Staff and Students Publications

Folate deficiency contribute to neural tube defects (NTDs) which could be rescued by folate supplementation. However, the underlying mechanisms are still not fully understood. Besides, there is considerable controversy concerning the forms of folate used for supplementation. To address this controversy, we prepared culture medium with different forms of folate, Folic acid (FA) and 5-methyltetrahydrofolate(5mTHF), at concentration of 5uM, 500nM, 50nM and folate free, respectively. Mouse embryonic fibroblasts (MEFs) were treated with different folates continuously for three passages and cell proliferation and F-actin was monitored. We determined that compared to 5mTHF, FA showed stronger effects on promoting cell proliferation and …

Age-Associated Temporal Decline In Butyrate-Producing Bacteria Plays A Key Pathogenic Role In The Onset And Progression Of Neuropathology And Memory Deficits In 3×Tg-Ad Mice, Paula M Chilton, Smita S Ghare, Benjamin T Charpentier, Scott A Myers, Aakarsha V Rao, Joseph F Petrosino, Kristi L Hoffman, John C Greenwell, Neetu Tyagi, Jyotirmaya Behera, Yali Wang, Lucy J Sloan, Jingwen Zhang, Christopher B Shields, Gregory E Cooper, Leila Gobejishvili, Scott R Whittemore, Craig J Mcclain, Shirish S Barve

Faculty, Staff and Students Publications

Alterations in the gut-microbiome-brain axis are increasingly being recognized to be involved in Alzheimer's disease (AD) pathogenesis. However, the functional consequences of enteric dysbiosis linking gut microbiota and brain pathology in AD progression remain largely undetermined. The present work investigated the causal role of age-associated temporal decline in butyrate-producing bacteria and butyrate in the etiopathogenesis of AD. Longitudinal metagenomics, neuropathological, and memory analyses were performed in the 3×Tg-AD mouse model. Metataxonomic analyses showed a significant temporal decline in the alpha diversity marked by a decrease in butyrate-producing bacterial communities and a concurrent reduction in cecal butyrate production. Inferred metagenomics analysis …

Select Gut Microbiota Impede Rotavirus Vaccine Efficacy, Vu L Ngo, Yanling Wang, Yadong Wang, Zhenda Shi, Robert Britton, Jun Zou, Sasirekha Ramani, Baoming Jiang, Andrew T Gewirtz

Faculty, Staff and Students Publications

BACKGROUND & AIMS: The protection provided by rotavirus (RV) vaccines is highly heterogeneous among individuals. We hypothesized that microbiota composition might influence RV vaccine efficacy.

METHODS: First, we examined the potential of segmented filamentous bacteria (SFB) colonization to influence RV vaccine efficacy in mice. Next, we probed the influence of human microbiomes on RV vaccination via administering mice fecal microbial transplants (FMTs) from children with robust or minimal RV vaccine responsiveness. Post-FMT, mice were subjected to RV vaccination followed by RV challenge.

RESULTS: SFB colonization induced a phenotype that was reminiscent of RV vaccine failure (ie, failure to generate RV …

Triobp Modulates Β-Catenin Signaling By Regulation Of Mir-29b In Idiopathic Pulmonary Fibrosis, Lan Wang, Wenyu Zhao, Cong Xia, Shuaichen Ma, Zhongzheng Li, Ningdan Wang, Linke Ding, Yaxuan Wang, Lianhui Cheng, Huibing Liu, Juntang Yang, Yajun Li, Ivan Rosas, Guoying Yu

Faculty, Staff and Students Publications

Idiopathic pulmonary fibrosis (IPF) is a fatal and devastating lung disease of unknown etiology, described as the result of multiple cycles of epithelial cell injury and fibroblast activation. Despite this impressive increase in understanding, a therapy that reverses this form of fibrosis remains elusive. In our previous study, we found that miR-29b has a therapeutic effect on pulmonary fibrosis. However, its anti-fibrotic mechanism is not yet clear. Recently, our study identified that F-Actin Binding Protein (TRIOBP) is one of the target genes of miR-29b and found that deficiency of TRIOBP increases resistance to lung fibrosis in vivo. TRIOBP knockdown inhibited …

Cbx4 Promotes Antitumor Immunity By Suppressing Pdcd1 Expression In T Cells, Liwei Ren, Ziyin Li, Yu Zhou, Jun Zhang, Ziheng Zhao, Zhaofei Wu, Ye Zhao, Yurong Ju, Xuewen Pang, Xiuyuan Sun, Wei Wang, Yu Zhang

Faculty, Staff and Student Publications

E3 SUMO-protein ligase CBX4 (CBX4), a key component of polycomb-repressive complexes 1 (PRC1), has been reported to regulate a variety of genes implicated in tumor growth, metastasis, and angiogenesis. However, its role in T-cell-mediated antitumor immunity remains elusive. To shed light on this issue, we generated mice with T-cell-specific deletion of Cbx4. Tumor growth was increased in the knockout mice. Additionally, their tumor-infiltrating lymphocytes exhibited impaired tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) production, with an elevated programmed cell death protein 1 (PD-1) level. In fact, dysregulated Pdcd1 expression was observed in all major subsets of peripheral T cells from …

Microbial Stimulation Of Oxytocin Release From The Intestinal Epithelium Via Secretin Signaling, Heather A Danhof, Jihwan Lee, Aanchal Thapa, Robert A Britton, Sara C Di Rienzi

Faculty, Staff and Students Publications

Intestinal microbes impact the health of the intestine and organs distal to the gut. Limosilactobacillus reuteri is a human intestinal microbe that promotes normal gut transit, the anti-inflammatory immune system, wound healing, normal social behavior in mice, and prevents bone reabsorption. Oxytocin impacts these functions and oxytocin signaling is required for L. reuteri-mediated wound healing and social behavior; however, the events in the gut leading to oxytocin stimulation and beneficial effects are unknown. Here we report evolutionarily conserved oxytocin production in the intestinal epithelium through analysis of single-cell RNA-Seq datasets and imaging of human and mouse intestinal tissues. Moreover, …

The Brd4-Nut Fusion Alone Drives Malignant Transformation Of Nut Carcinoma, R Taylor Durall, Julianna Huang, Luke Wojenski, Yeying Huang, Prafulla C Gokhale, Brittaney A Leeper, Joshua O Nash, Pedro L Ballester, Scott Davidson, Adam Shlien, Emmanuel Sotirakis, Fabien Bertaux, Vincent Dubus, Jia Luo, Catherine J Wu, Derin B Keskin, Kyle P Eagen, Geoffrey I Shapiro, Christopher A French

Faculty, Staff and Students Publications

NUT carcinoma (NC) is an aggressive squamous carcinoma defined by the BRD4-NUT fusion oncoprotein. Routinely effective systemic treatments are unavailable for most NC patients. The lack of an adequate animal model precludes identifying and leveraging cell-extrinsic factors therapeutically in NC. Here, we created a genetically engineered mouse model (GEMM) of NC that forms a Brd4::NUTM1 fusion gene upon tamoxifen induction of Sox2-driven Cre. The model displayed complete disease penetrance, with tumors arising from the squamous epithelium weeks after induction and all mice succumbing to the disease shortly thereafter. Closely resembling human NC (hNC), GEMM tumors (mNC) were poorly differentiated squamous …

Vaginal Microbial Dynamics And Pathogen Colonization In A Humanized Microbiota Mouse Model, Marlyd E Mejia, Vicki Mercado-Evans, Jacob J Zulk, Samantha Ottinger, Korinna Ruiz, Mallory B Ballard, Stephanie W Fowler, Robert A Britton, Kathryn A Patras

Faculty, Staff and Students Publications

Vaginal microbial composition is associated with differential risk of urogenital infection. Although Lactobacillus spp. are thought to confer protection against infection, the lack of in vivo models resembling the human vaginal microbiota remains a prominent barrier to mechanistic discovery. Using 16S rRNA amplicon sequencing of C57BL/6J female mice, we found that vaginal microbial composition varies within and between colonies across three vivaria. Noting vaginal microbial plasticity in conventional mice, we assessed the vaginal microbiome of humanized microbiota mice (

Nad+ Rescues Aging-Induced Blood-Brain Barrier Damage Via The Cx43-Parp1 Axis, Rui Zhan, Xia Meng, Dongping Tian, Jie Xu, Hongtu Cui, Jialei Yang, Yangkai Xu, Mingming Shi, Jing Xue, Weiwei Yu, Gaofei Hu, Ke Li, Xiaoxiao Ge, Qi Zhang, Mingming Zhao, Jianyong Du, Xin Guo, Wenli Xu, Yang Gao, Changyu Yao, Fan Chen, Yue Chen, Wenxin Shan, Yujie Zhu, Liang Ji, Bing Pan, Yan Yu, Wenguang Li, Xuyang Zhao, Qihua He, Xiaohui Liu, Yue Huang, Shengyou Liao, Bin Zhou, Dehua Chui, Y Eugene Chen, Zheng Sun, Erdan Dong, Yongjun Wang, Lemin Zheng

Faculty, Staff and Students Publications

Blood-brain barrier (BBB) function deteriorates during aging, contributing to cognitive impairment and neurodegeneration. It is unclear what drives BBB leakage in aging and how it can be prevented. Using single-nucleus transcriptomics, we identified decreased connexin 43 (CX43) expression in cadherin-5

Srcap Mutations Drive Clonal Hematopoiesis Through Epigenetic And Dna Repair Dysregulation, Chun-Wei Chen, Linda Zhang, Ravi Dutta, Abhishek Niroula, Peter G Miller, Christopher J Gibson, Alexander G Bick, Jaime M Reyes, Yi-Tang Lee, Ayala Tovy, Tianpeng Gu, Sarah Waldvogel, Yi-Hung Chen, Bryan J Venters, Pierre-Olivier Estève, Sriharsa Pradhan, Michael-Christopher Keogh, Pradeep Natarajan, Koichi Takahashi, Adam S Sperling, Margaret A Goodell

Faculty, Staff and Students Publications

Somatic mutations accumulate in all cells with age and can confer a selective advantage, leading to clonal expansion over time. In hematopoietic cells, mutations in a subset of genes regulating DNA repair or epigenetics frequently lead to clonal hematopoiesis (CH). Here, we describe the context and mechanisms that lead to enrichment of hematopoietic stem cells (HSCs) with mutations in SRCAP, which encodes a chromatin remodeler that also influences DNA repair. We show that SRCAP mutations confer a selective advantage in human cells and in mice upon treatment with the anthracycline-class chemotherapeutic doxorubicin and bone marrow transplantation. Furthermore, Srcap mutations lead …

Targeted Inhibition Of Lncrna Malat1 Alters The Tumor Immune Microenvironment In Preclinical Syngeneic Mouse Models Of Triple-Negative Breast Cancer, Oluwatoyosi Adewunmi, Yichao Shen, Xiang H-F Zhang, Jeffrey M Rosen

Faculty, Staff and Students Publications

Long noncoding RNAs (lncRNA) play an important role in gene regulation in both normal tissues and cancer. Targeting lncRNAs is a promising therapeutic approach that has become feasible through the development of gapmer antisense oligonucleotides (ASO). Metastasis-associated lung adenocarcinoma transcript (Malat1) is an abundant lncRNA whose expression is upregulated in several cancers. Although Malat1 increases the migratory and invasive properties of tumor cells, its role in the tumor microenvironment (TME) is still not well defined. We explored the connection between Malat1 and the tumor immune microenvironment (TIME) using several immune-competent preclinical syngeneic Tp53-null triple-negative breast cancer (TNBC) mouse models that …

P2y2 Purinergic Receptor Gene Deletion Protects Mice From Bacterial Endotoxin And Sepsis-Associated Liver Injury And Mortality, Athis R Arunachalam, Sanju S Samuel, Arunmani Mani, Janielle P Maynard, Kelsey M Stayer, Eric Dybbro, Subapradha Narayanan, Aalekhya Biswas, Saliha Pathan, Krishnakant Soni, Abu Hena Mostafa Kamal, Chandra Shekar R Ambati, Nagireddy Putluri, Moreshwar S Desai, Sundararajah Thevananther

Faculty, Staff and Students Publications

Prostate cancer (PCa) remains a leading cause of mortality among American men, with metastatic and recurrent disease posing significant therapeutic challenges due to a limited comprehension of the underlying biological processes governing disease initiation, dormancy, and progression. The conventional use of PCa cell lines has proven inadequate in elucidating the intricate molecular mechanisms driving PCa carcinogenesis, hindering the development of effective treatments. To address this gap, patient-derived primary cell cultures have been developed and play a pivotal role in unraveling the pathophysiological intricacies unique to PCa in each individual, offering valuable insights for translational research. This review explores the applications …

Camkk2 As An Emerging Treatment Target For Bipolar Disorder, Jacqueline Kaiser, Kevin Nay, Christopher R Horne, Luke M Mcaloon, Oliver K Fuller, Abbey G Muller, Douglas G Whyte, Anthony R Means, Ken Walder, Michael Berk, Anthony J Hannan, James M Murphy, Mark A Febbraio, Andrew L Gundlach, John W Scott

Faculty, Staff and Students Publications

Current pharmacological treatments for bipolar disorder are inadequate and based on serendipitously discovered drugs often with limited efficacy, burdensome side-effects, and unclear mechanisms of action. Advances in drug development for the treatment of bipolar disorder remain incremental and have come largely from repurposing drugs used for other psychiatric conditions, a strategy that has failed to find truly revolutionary therapies, as it does not target the mood instability that characterises the condition. The lack of therapeutic innovation in the bipolar disorder field is largely due to a poor understanding of the underlying disease mechanisms and the consequent absence of validated drug …