Microbiology Commons^™

Multifactoral Immune Modulation Potentiates Durable Remission In Multiple Models Of Aggressive Malignancy, Matthew M Halpert, Briana A Burns, Spencer R Rosario, Henry G Withers, Akshar J Trivedi, Colby J Hofferek, Benjamin D Gephart, Haotong Wang, Jonathan Vazquez-Perez, Sharon B Amanya, Sean T Hyslop, Jianhua Yang, Jan O Kemnade, Vlad C Sandulache, Vanaja Konduri, William K Decker

Faculty, Staff and Students Publications

Tumors typically lack canonical danger signals required to activate adaptive immunity and also frequently employ substantial immunomodulatory mechanisms that downregulate adaptive responses and contribute to escape from immune surveillance. Given the variety of mechanisms involved in shielding tumors from immune recognition, it is not surprising that single-agent immunomodulatory approaches have been largely unsuccessful in generating durable antitumor responses. Here we report a unique combination of immunomodulatory and cytostatic agents that recondition the tumor microenvironment and eliminate complex and/or poor-prognosis tumor types including the non-immunogenic 4T-1 model of TNBC, the aggressive MOC-2 model of HNSCC, and the high-risk MYCN-amplified model of …

Generation Of Oviductal Glycoprotein 1 Cre Mouse Model For The Study Of Secretory Epithelial Cells Of The Oviduct, Emily A Mcglade, Jiude Mao, Kalli K Stephens, Andrew M Kelleher, Lisette A Maddison, Miranda L Bernhardt, Francesco J Demayo, John P Lydon, Wipawee Winuthayanon

Faculty, Staff and Students Publications

The epithelial cell lining of the oviduct plays an important role in oocyte pickup, sperm migration, preimplantation embryo development, and embryo transport. The oviduct epithelial cell layer comprises ciliated and nonciliated secretory cells. The ciliary function has been shown to support gamete and embryo movement in the oviduct, yet secretory cell function has not been well characterized. Therefore, our goal was to generate a secretory cell-specific Cre recombinase mouse model to study the role of the oviductal secretory cells. A knock-in mouse model, Ovgp1Cre:eGFP, was created by expressing Cre from the endogenous Ovgp1 (oviductal glycoprotein 1) locus, with enhanced green …

Optical Coherence Tomography-Guided Brillouin Microscopy Highlights Regional Tissue Stiffness Differences During Anterior Neural Tube Closure In The Mthfd1l Murine Mutant, Yogeshwari S Ambekar, Carlo Donato Caiaffa, Bogdan J Wlodarczyk, Manmohan Singh, Alexander W Schill, John W Steele, Jitao Zhang, Salavat R Aglyamov, Giuliano Scarcelli, Richard H Finnell, Kirill V Larin

Faculty, Staff and Students Publications

Neurulation is a highly synchronized biomechanical process leading to the formation of the brain and spinal cord, and its failure leads to neural tube defects (NTDs). Although we are rapidly learning the genetic mechanisms underlying NTDs, the biomechanical aspects are largely unknown. To understand the correlation between NTDs and tissue stiffness during neural tube closure (NTC), we imaged an NTD murine model using optical coherence tomography (OCT), Brillouin microscopy and confocal fluorescence microscopy. Here, we associate structural information from OCT with local stiffness from the Brillouin signal of embryos undergoing neurulation. The stiffness of neuroepithelial tissues in Mthfd1l null embryos …

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 …

Metaplastic Regeneration In The Mouse Stomach Requires A Reactive Oxygen Species Pathway, Zhi-Feng Miao, Jing-Xu Sun, Xuan-Zhang Huang, Shi Bai, Min-Jiao Pang, Jia-Yi Li, Han-Yu Chen, Qi-Yue Tong, Shi-Yu Ye, Xin-Yu Wang, Xiao-Hai Hu, Jing-Ying Li, Jin-Wei Zou, Wen Xu, Jun-Hao Yang, Xi Lu, Jason C Mills, Zhen-Ning Wang

Faculty, Staff and Students Publications

In pyloric metaplasia, mature gastric chief cells reprogram via an evolutionarily conserved process termed paligenosis to re-enter the cell cycle and become spasmolytic polypeptide-expressing metaplasia (SPEM) cells. Here, we use single-cell RNA sequencing (scRNA-seq) following injury to the murine stomach to analyze mechanisms governing paligenosis at high resolution. Injury causes induced reactive oxygen species (ROS) with coordinated changes in mitochondrial activity and cellular metabolism, requiring the transcriptional mitochondrial regulator Ppargc1a (Pgc1α) and ROS regulator Nf2el2 (Nrf2). Loss of the ROS and mitochondrial control in Ppargc1a-/- mice causes the death of paligenotic cells through ferroptosis. Blocking the cystine transporter SLC7A11(xCT), which …

Mechanisms Driving Fasting-Induced Protection From Genotoxic Injury In The Small Intestine, Kali Deans-Fielder, Timothy Wu, Thanh Nguyen, Sarah To, Yang-Zhe Huang, Steven J Bark, Jason C Mills, Noah F Shroyer

Faculty, Staff and Students Publications

Genotoxic agents such as doxorubicin (DXR) can cause damage to the intestines that can be ameliorated by fasting. How fasting is protective and the optimal timing of fasting and refeeding remain unclear. Here, our analysis of fasting/refeeding-induced global intestinal transcriptional changes revealed metabolic shifts and implicated the cellular energetic hub mechanistic target of rapamycin complex 1 (mTORC1) in protecting from DXR-induced DNA damage. Our analysis of specific transcripts and proteins in intestinal tissue and tissue extracts showed that fasting followed by refeeding at the time of DXR administration reduced damage and caused a spike in mTORC1 activity. However, continued fasting …

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 …

Monophosphoryl Lipid A-Based Adjuvant To Promote The Immunogenicity Of Multivalent Meningococcal Polysaccharide Conjugate Vaccines, Kishore Alugupalli

Department of Microbiology and Immunology Faculty Papers

Activation of the adaptive immune system requires the engagement of costimulatory pathways in addition to B and T cell Ag receptor signaling, and adjuvants play a central role in this process. Many Gram-negative bacterial polysaccharide vaccines, including the tetravalent meningococcal conjugate vaccines (MCV4) and typhoid Vi polysaccharide vaccines, do not incorporate adjuvants. The immunogenicity of typhoid vaccines is due to the presence of associated TLR4 ligands in these vaccines. Because the immunogenicity of MCV4 is poor and requires boosters, I hypothesized that TLR4 ligands are absent in MCV4 and that incorporation of a TLR4 ligand-based adjuvant would improve their immunogenicity. …

A Mutation In Tbxt Causes Congenital Vertebral Malformations In Humans And Mice, Shuxia Chen, Yunping Lei, Yajun Yang, Chennan Liu, Lele Kuang, Li Jin, Richard H Finnell, Xueyan Yang, Hongyan Wang

Faculty, Staff and Students Publications

T-box transcription factor T (TBXT; T) is required for mesodermal formation and axial skeletal development. Although it has been extensively studied in various model organisms, human congenital vertebral malformations (CVMs) involving T are not well established. Here, we report a family with 15 CVM patients distributed across 4 generations. All affected individuals carry a heterozygous mutation, T c.596A>G (p.Q199R), which is not found in unaffected family members, indicating co-segregation of the genotype and phenotype. In vitro assays show that T p.Q199R increases the nucleocytoplasmic ratio and enhances its DNA-binding affinity, but reduces its transcriptional activity compared to the wild-type. …

An Oocyte-Specific Cas9-Expressing Mouse For Germline Crispr/Cas9-Mediated Genome Editing, Denise G Lanza, Jianqiang Mao, Isabel Lorenzo, Lan Liao, John R Seavitt, M Cecilia Ljungberg, Elizabeth M Simpson, Francesco J Demayo, Jason D Heaney

Faculty, Staff and Students Publications

Cas9 transgenes can be employed for genome editing in mouse zygotes. However, using transgenic instead of exogenous Cas9 to produce gene-edited animals creates unique issues including ill-defined transgene integration sites, the potential for prolonged Cas9 expression in transgenic embryos, and increased genotyping burden. To overcome these issues, we generated mice harboring an oocyte-specific, Gdf9 promoter driven, Cas9 transgene (Gdf9-Cas9) targeted as a single copy into the Hprt1 locus. The X-linked Hprt1 locus was selected because it is a defined integration site that does not influence transgene expression, and breeding of transgenic males generates obligate transgenic females to serve as embryo …

Dolutegravir-Induced Neural Tube Defects In Mice Are Folate Responsive, Gabriel L Tukeman, Hui Wei, Ying L Lin, Bogdan J Wlodarczyk, Richard H Finnell, Robert M Cabrera

Faculty, Staff and Students Publications

Objectives: In 2018, the Botswana Tsepamo Study reported a nine-fold increased risk of neural tube defects in infants whose mothers were treated with dolutegravir (DTG) from the time of conception. As maternal folate supplementation and status is a well known modifier of neural tube defect (NTD) risk, we sought to evaluate birth outcomes in mice fed normal and low folic acid diets treated with DTG during pregnancy.

Design: DTG was evaluated for developmental toxicity using pregnant mice fed normal or low folic acid diet.

Methods: CD-1 mice were provided diet with normal (3 mg/kg) or low (0.3 mg/kg) folic acid. …

Highlights Of How Single-Cell Analyses Are Illuminating Differentiation And Disease In The Gastric Corpus, Mahliyah Adkins-Threats, Yang-Zhe Huang, Jason C Mills

Faculty, Staff and Students Publications

Single-cell RNA-sequencing (scRNA-seq) has emerged as a powerful technique to identify novel cell markers, developmental trajectories, and transcriptional changes during cell differentiation and disease onset and progression. In this review, we highlight recent scRNA-seq studies of the gastric corpus in both human and murine systems that have provided insight into gastric organogenesis, identified novel markers for the various gastric lineages during development and in adults, and revealed transcriptional changes during regeneration and tumorigenesis. Overall, by elucidating transcriptional states and fluctuations at the cellular level in healthy and disease contexts, scRNA-seq may lead to better, more personalized clinical treatments for disease …

The Human Vaginal Microbiota: From Clinical Medicine To Models To Mechanisms, Samantha Ottinger, Clare M Robertson, Holly Branthoover, Kathryn A Patras

Faculty, Staff and Students Publications

The composition of the vaginal microbiota is linked to numerous reproductive health problems, including increased susceptibility to infection, pregnancy complications, and impaired vaginal tissue repair; however, the mechanisms contributing to these adverse outcomes are not yet fully defined. In this review, we highlight recent clinical advancements associating vaginal microbiome composition and function with health outcomes. Subsequently, we provide a summary of emerging models employed to identify microbe-microbe interactions contributing to vaginal health, including metagenomic sequencing, multi-omics approaches, and advances in vaginal microbiota cultivation. Last, we review new in vitro, ex vivo, and in vivo models, such as organoids and humanized …

Secreted Igm Modulates Il-10 Expression In B Cells, Shannon Mcgettigan, Lazaro Aira, Gaurav Kumar, Romain Ballet, Eugene Butcher, Nicole Baumgarth, Gudrun Debes

Department of Microbiology and Immunology Faculty Papers

IL-10⁺ B cells are critical for immune homeostasis and restraining immune responses in infection, cancer, and inflammation; however, the signals that govern IL-10⁺ B cell differentiation are ill-defined. Here we find that IL-10⁺ B cells expand in mice lacking secreted IgM ((s)IgM^–/–) up to 10-fold relative to wildtype (WT) among all major B cell and regulatory B cell subsets. The IL-10⁺ B cell increase is polyclonal and presents within 24 hours of birth. In WT mice, sIgM is produced prenatally and limits the expansion of IL-10⁺ B cells. Lack of the high affinity …

Listeria Adhesion Protein Orchestrates Caveolae-Mediated Apical Junctional Remodeling Of Epithelial Barrier For Listeria Monocytogenes Translocation, Rishi Drolia, Donald B. Bryant, Shivendra Tenguria, Zuri A. Jules-Culver, Jessie Thind, Breanna Amelunke, Donqi Liu, Nicholas L. F. Gallina, Krishna K. Mishra, Manalee Samaddar, Manoj R. Sawale, Dharmendra K. Mishra, Abigail D. Cox, Arun K. Bhunia

Biological Sciences Faculty Publications

The cellular junctional architecture remodeling by Listeria adhesion protein-heat shock protein 60 (LAP-Hsp60) interaction for Listeria monocytogenes (Lm) passage through the epithelial barrier is incompletely understood. Here, using the gerbil model, permissive to internalin (Inl) A/B-mediated pathways like in humans, we demonstrate that Lm crosses the intestinal villi at 48 h post-infection. In contrast, the single isogenic (lap− or ΔinlA) or double (lap−ΔinlA) mutant strains show significant defects. LAP promotes Lm translocation via endocytosis of cell-cell junctional complex in enterocytes that do not display luminal E-cadherin. In comparison, InlA facilitates …

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 …

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 …

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, …

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 (

Dietary L-Tryptophan Consumption Determines The Number Of Colonic Regulatory T Cells And Susceptibility To Colitis Via Gpr15, Nguyen Van, Karen Zhang, Rachel Wigmore, Anne Kennedy, Carolina Dasilva, Jialing Huang, Manju Ambelil, Jose Villagomez, Gerald O'Connor, Randy Longman, Miao Cao, Adam Snook, Michael Platten, Gerard Kasenty, Luis Sigal, George C Prendergast, Sangwon Kim

Department of Microbiology and Immunology Faculty Papers

Environmental factors are the major contributor to the onset of immunological disorders such as ulcerative colitis. However, their identities remain unclear. Here, we discover that the amount of consumed L-Tryptophan (L-Trp), a ubiquitous dietary component, determines the transcription level of the colonic T cell homing receptor, GPR15, hence affecting the number of colonic FOXP3⁺ regulatory T (Treg) cells and local immune homeostasis. Ingested L-Trp is converted by host IDO1/2 enzymes, but not by gut microbiota, to compounds that induce GPR15 transcription preferentially in Treg cells via the aryl hydrocarbon receptor. Consequently, two weeks of dietary L-Trp supplementation nearly double …

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

The liver plays a significant role in regulating a wide range of metabolic, homeostatic, and host-defense functions. However, the impact of liver injury on the host's ability to control bacteremia and morbidity in sepsis is not well understood. Leukocyte recruitment and activation lead to cytokine and chemokine release, which, in turn, trigger hepatocellular injury and elevate nucleotide levels in the extracellular milieu. P2Y2 purinergic receptors, G protein-coupled and activated by extracellular ATP/UTP, are expressed at the cell surface of hepatocytes and nonparenchymal cells. We sought to determine whether P2Y2 purinergic receptor function is necessary for the maladaptive host response to …

Flavonoids Quercetin And Kaempferol Are Nr4a1 Antagonists And Suppress Endometriosis In Female Mice, Lei Zhang, Kumaravel Mohankumar, Gregory Martin, Fuada Mariyam, Yuri Park, Sang Jun Han, Stephen Safe

Faculty, Staff and Students Publications

Nuclear receptor 4A1 (NR4A1) plays an important role in endometriosis progression; levels of NR4A1 in endometriotic lesions are higher than in normal endometrium, and substituted bis-indole analogs (NR4A1) antagonists suppress endometriosis progression in mice with endometriosis. In addition, the flavonoids kaempferol and quercetin are natural products that directly bind NR4A1 and significantly repress the intrinsic NR4A1-dependent transcriptional activity in human endometriotic epithelial and stromal cells and Ishikawa endometrial cancer cells. NR4A1 knockdown and inhibition of NR4A1 by kaempferol and quercetin suppressed proliferation of human endometriotic epithelial cells and Ishikawa cells by inhibiting epidermal growth factor receptor/c-Myc/survivin-mediated growth-promoting and survival pathways, …

Identifying Proteins That Interact With Human Pas Kinase, Tacie Hall, Dr. Julianne Grose

Journal of Undergraduate Research

When PAS kinase is knocked out in mice placed on high-fat diets, these mice show such symptoms as decreased weight gain, hypermetabolic phenotype, decreased liver triglyceride accumulation, and retained insulin sensitivity when compared with their wild type littermates.¹ These symptoms are highly associated with chronic diseases commonly seen in humans today, such as diabetes, obesity, and heart disease. PAS kinase is a highly conserved protein from yeast to man which allows for the use of yeast as model organism to help discover the molecular mechanisms behind PAS kinase function. Since little is known about how PAS kinase functions, it …

Gpr43 Stimulation On Tcrαβ+ Intraepithelial Colonic Lymphocytes Inhibits The Recruitment Of Encephalitogenic T-Cells Into The Central Nervous System And Attenuates The Development Of Autoimmunity, Carolina Prado, Alexandra Espinoza, J Eduardo Martínez-Hernández, Joseph Petrosino, Erick Riquelme, Alberto J M Martin, Rodrigo Pacheco

Faculty, Staff and Students Publications

INTRODUCTION: Gut microbiota plays a critical role in the regulation of immune homeostasis. Accordingly, several autoimmune disorders have been associated with dysbiosis in the gut microbiota. Notably, the dysbiosis associated with central nervous system (CNS) autoimmunity involves a substantial reduction of bacteria belonging to Clostridia clusters IV and XIVa, which constitute major producers of short-chain fatty acids (SCFAs). Here we addressed the role of the surface receptor-mediated effects of SCFAs on mucosal T-cells in the development of CNS autoimmunity.

METHODS: To induce CNS autoimmunity, we used the mouse model of experimental autoimmune encephalomyelitis (EAE) induced by immunization with the myelin …

Co-Clinical Imaging Metadata Information (Cimi) For Cancer Research To Promote Open Science, Standardization, And Reproducibility In Preclinical Imaging, Stephen M Moore, James D Quirk, Andrew W Lassiter, Richard Laforest, Gregory D Ayers, Cristian T Badea, Andriy Y Fedorov, Paul E Kinahan, Matthew Holbrook, Peder E Z Larson, Renuka Sriram, Thomas L Chenevert, Dariya Malyarenko, John Kurhanewicz, A Mcgarry Houghton, Brian D Ross, Stephen Pickup, James C Gee, Rong Zhou, Seth T Gammon, Henry Charles Manning, Raheleh Roudi, Heike E Daldrup-Link, Michael T Lewis, Daniel L Rubin, Thomas E Yankeelov, Kooresh I Shoghi

Faculty, Staff and Students Publications

Preclinical imaging is a critical component in translational research with significant complexities in workflow and site differences in deployment. Importantly, the National Cancer Institute's (NCI) precision medicine initiative emphasizes the use of translational co-clinical oncology models to address the biological and molecular bases of cancer prevention and treatment. The use of oncology models, such as patient-derived tumor xenografts (PDX) and genetically engineered mouse models (GEMMs), has ushered in an era of co-clinical trials by which preclinical studies can inform clinical trials and protocols, thus bridging the translational divide in cancer research. Similarly, preclinical imaging fills a translational gap as an …

Exercise Reprograms The Inflammatory Landscape Of Multiple Stem Cell Compartments During Mammalian Aging, Ling Liu, Soochi Kim, Matthew T Buckley, Jaime M Reyes, Jengmin Kang, Lei Tian, Mingqiang Wang, Alexander Lieu, Michelle Mao, Cristina Rodriguez-Mateo, Heather D Ishak, Mira Jeong, Joseph C Wu, Margaret A Goodell, Anne Brunet, Thomas A Rando

Faculty, Staff and Students Publications

Exercise has the ability to rejuvenate stem cells and improve tissue regeneration in aging animals. However, the cellular and molecular changes elicited by exercise have not been systematically studied across a broad range of cell types in stem cell compartments. We subjected young and old mice to aerobic exercise and generated a single-cell transcriptomic atlas of muscle, neural, and hematopoietic stem cells with their niche cells and progeny, complemented by whole transcriptome analysis of single myofibers. We found that exercise ameliorated the upregulation of a number of inflammatory pathways associated with old age and restored aspects of intercellular communication mediated …

Pattern Dynamics And Stochasticity Of The Brain Rhythms, Clarissa Hoffman, Jingheng Cheng, Daoyun Ji, Yuri Dabaghian

Faculty, Staff and Students Publications

Our current understanding of brain rhythms is based on quantifying their instantaneous or time-averaged characteristics. What remains unexplored is the actual structure of the waves—their shapes and patterns over finite timescales. Here, we study brain wave patterning in different physiological contexts using two independent approaches: The first is based on quantifying stochasticity relative to the underlying mean behavior, and the second assesses “orderliness” of the waves’ features. The corresponding measures capture the waves’ characteristics and abnormal behaviors, such as atypical periodicity or excessive clustering, and demonstrate coupling between the patterns’ dynamics and the animal’s location, speed, and acceleration. Specifically, we …

Neuronal Sirt3 Deletion Predisposes To Female-Specific Alterations In Cellular Metabolism, Memory, And Network Excitability, Jennifer N Pearson-Smith, Ruth Fulton, Christopher Q Huynh, Anna G Figueroa, Gia B Huynh, Li-Ping Liang, Lindsey B Gano, Cole R Michel, Nichole Reisdorph, Richard Reisdorph, Kristofer S Fritz, Eric Verdin, Manisha Patel

Faculty, Staff and Students Publications

Mitochondrial dysfunction is an early event in the pathogenesis of neurologic disorders and aging. Sirtuin 3 (SIRT3) regulates mitochondrial function in response to the cellular environment through the reversible deacetylation of proteins involved in metabolism and reactive oxygen species detoxification. As the primary mitochondrial deacetylase, germline, or peripheral tissue-specific deletion of SIRT3 produces mitochondrial hyperacetylation and the accelerated development of age-related diseases. Given the unique metabolic demands of neurons, the role of SIRT3 in the brain is only beginning to emerge. Using mass spectrometry-based acetylomics, high-resolution respirometry, video-EEG, and cognition testing, we report targeted deletion of SIRT3 from select neurons …

Acute High-Fat Diet Impairs Macrophage-Supported Intestinal Damage Resolution, Andrea A Hill, Myunghoo Kim, Daniel F Zegarra-Ruiz, Lin-Chun Chang, Kendra Norwood, Adrien Assié, Wan-Jung H Wu, Michael C Renfroe, Hyo Wong Song, Angela M Major, Buck S Samuel, Joseph M Hyser, Randy S Longman, Gretchen E Diehl

Faculty, Staff and Students Publications

Chronic exposure to high-fat diets (HFD) worsens intestinal disease pathology, but acute effects of HFD in tissue damage remain unclear. Here, we used short-term HFD feeding in a model of intestinal injury and found sustained damage with increased cecal dead neutrophil accumulation, along with dietary lipid accumulation. Neutrophil depletion rescued enhanced pathology. Macrophages from HFD-treated mice showed reduced capacity to engulf dead neutrophils. Macrophage clearance of dead neutrophils activates critical barrier repair and antiinflammatory pathways, including IL-10, which was lost after acute HFD feeding and intestinal injury. IL-10 overexpression restored intestinal repair after HFD feeding and intestinal injury. Macrophage exposure …

Sumoylation Regulates Functional Properties Of The Oocyte Transcription Factors Sohlh1 And Nobox, Bethany K Patton, Surabhi Madadi, Shawn M Briley, Avery A Ahmed, Stephanie A Pangas

Faculty, Staff and Students Publications

SOHLH1 and NOBOX are oocyte-expressed transcription factors with critical roles in ovary development and fertility. In mice, Sohlh1 and Nobox are essential for fertility through their regulation of the oocyte transcriptional network and cross-talk to somatic cells. Sumoylation is a posttranslational modification that regulates transcription factor function, and we previously showed that mouse oocytes deficient for sumoylation had an altered transcriptional landscape that included significant changes in NOBOX target genes. Here, we show that mouse SOHLH1 is modified by SUMO2/3 at lysine 345 and mutation of this residue alters SOHLH1 nuclear to cytoplasmic localization. In NOBOX, we identify a non-consensus …