Medical Microbiology Commons^™

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 …

Post-Transcriptional Regulation In Cranial Neural Crest Cells Expands Developmental Potential, Rachel A Keuls, Young Sun Oh, Ivanshi Patel, Ronald J Parchem

Faculty, Staff and Students Publications

Developmental potential is progressively restricted after germ layer specification during gastrulation. However, cranial neural crest cells challenge this paradigm, as they develop from anterior ectoderm, yet give rise to both ectodermal derivatives of the peripheral nervous system and ectomesenchymal bone and cartilage. How cranial neural crest cells differentiate into multiple lineages is poorly understood. Here, we demonstrate that cranial neural crest cells possess a transient state of increased chromatin accessibility. We profile the spatiotemporal emergence of premigratory neural crest and find evidence of lineage bias toward either a neuronal or ectomesenchymal fate, with each expressing distinct factors from earlier stages …

Bone Metastasis Initiation Is Coupled With Bone Remodeling Through Osteogenic Differentiation Of Ng2+ Cells, Weijie Zhang, Zhan Xu, Xiaoxin Hao, Tiancheng He, Jiasong Li, Yichao Shen, Kai Liu, Yang Gao, Jun Liu, David G Edwards, Aaron M Muscarella, Ling Wu, Liqun Yu, Longyong Xu, Xi Chen, Yi-Hsuan Wu, Igor L Bado, Yunfeng Ding, Sergio Aguirre, Hai Wang, Zbigniew Gugala, Robert L Satcher, Stephen T C Wong, Xiang H-F Zhang

Faculty, Staff and Students Publications

The bone microenvironment is dynamic and undergoes remodeling in normal and pathologic conditions. Whether such remodeling affects disseminated tumor cells (DTC) and bone metastasis remains poorly understood. Here, we demonstrated that pathologic fractures increase metastatic colonization around the injury. NG2+ cells are a common participant in bone metastasis initiation and bone remodeling in both homeostatic and fractured conditions. NG2+ bone mesenchymal stem/stromal cells (BMSC) often colocalize with DTCs in the perivascular niche. Both DTCs and NG2+ BMSCs are recruited to remodeling sites. Ablation of NG2+ lineage impaired bone remodeling and concurrently diminished metastatic colonization. In cocultures, NG2+ BMSCs, especially when …

Short-Term Pi3k Inhibition Prevents Breast Cancer In Preclinical Models, Amy T Ku, Adelaide I J Young, Ahmed Atef Ibrahim, Wen Bu, Weiyu Jiang, Meng Lin, Laterrica C Williams, Bryant Lee Mccue, George Miles, Chandandeep Nagi, Fariba Behbod, Yi Li

Faculty, Staff and Students Publications

Antiestrogen medication is the only chemoprevention currently available for women at a high risk of developing breast cancer; however, antiestrogen therapy requires years to achieve efficacy and has adverse side effects. Therefore, it is important to develop an efficacious chemoprevention strategy that requires only a short course of treatment. PIK3CA is commonly activated in breast atypical hyperplasia, the known precancerous precursor of breast cancer. Targeting PI3K signaling in these precancerous lesions may offer a new strategy for chemoprevention. Here, we first established a mouse model that mimics the progression from precancerous lesions to breast cancer. Next, we demonstrated that a …

Lef1 Drives A Central Memory Program And Supports Antitumor Activity Of Natural Killer T Cells, Ho Ngai, Gabriel A Barragan, Gengwen Tian, Julien C Balzeau, Chunchao Zhang, Amy N Courtney, Linjie Guo, Xin Xu, Michael S Wood, Janice M Drabek, Thorsten Demberg, Caroline M Sands, Cynthia N Chauvin-Fleurence, Erica J Di Pierro, Jeffrey M Rosen, Leonid S Metelitsa

Faculty, Staff and Students Publications

Vα24-invariant natural killer T cells (NKT) possess innate antitumor properties that can be exploited for cancer immunotherapy. We have shown previously that the CD62L+ central memory-like subset of these cells drives the in vivo antitumor activity of NKTs, but molecular mediators of NKT central memory differentiation remain unknown. Here, we demonstrate that relative to CD62L- cells, CD62L+ NKTs express a higher level of the gene encoding the Wnt/β-catenin transcription factor lymphoid enhancer binding factor 1 (LEF1) and maintain active Wnt/β-catenin signaling. CRISPR/Cas9-mediated LEF1 knockout reduced CD62L+ frequency after antigenic stimulation, whereas Wnt/β-catenin activator Wnt3a ligand increased CD62L+ frequency. LEF1 overexpression …

Ifn-Γ Production By Brain-Resident Cells Activates Cerebral Mrna Expression Of A Wide Spectrum Of Molecules Critical For Both Innate And T Cell-Mediated Protective Immunity To Control Reactivation Of Chronic Infection With Toxoplasma Gondii, Yasuhiro Suzuki, Jenny Lutshumba, Kuey Chu Chen, Mohamed H. Abdelaziz, Qila Sa, Eri Ochiai

Markey Cancer Center Faculty Publications

We previously demonstrated that brain-resident cells produce IFN-g in response to reactivation of cerebral infection with Toxoplasma gondii. To obtain an overall landscape view of the effects of IFN-g from brain-resident cells on the cerebral protective immunity, in the present study we employed NanoString nCounter assay and quantified mRNA levels for 734 genes in myeloid immunity in the brains of T and B cell-deficient, bone marrow chimeric mice with and without IFN-g production by brain-resident cells in response to reactivation of cerebral T. gondii infection. Our study revealed that IFN-g produced by brain-resident cells amplified mRNA expression for the molecules …

Clinical Characteristics, Microbiology And Outcomes Of A Cohort Of Patients Treated With Ceftolozane/Tazobactam In Acute Care Inpatient Facilities, Houston, Texas, Usa, Truc T Tran, Nicolo L Cabrera, Anne J Gonzales-Luna, Travis J Carlson, Faris Alnezary, William R Miller, Aki Sakurai, An Q Dinh, Kirsten Rydell, Rafael Rios, Lorena Diaz, Blake M Hanson, Jose M Munita, Claudia Pedroza, Samuel A Shelburne, Samuel L Aitken, Kevin W Garey, Ryan Dillon, Laura Puzniak, Cesar A Arias

Faculty, Staff and Student Publications

BACKGROUND: Ceftolozane/tazobactam is a β-lactam/β-lactamase inhibitor combination with activity against a variety of Gram-negative bacteria, including MDR

METHODS: We conducted a multicentre retrospective study of patients receiving at least 48 h of ceftolozane/tazobactam therapy from January 2016 through to September 2019 at two hospital systems in Houston. Demographic, clinical and microbiological data were collected, including the infecting bacterial isolate, when available. The primary outcome was composite clinical success at hospital discharge. Secondary outcomes included in-hospital mortality and clinical disposition at 14 and 30 days post ceftolozane/tazobactam initiation. Multivariable logistic regression analysis was used to identify predictors of the primary outcome …

The Alzheimer’S Disease Risk Factor Inpp5d Restricts Neuroprotective Microglial Responses In Amyloid Beta-Mediated Pathology, Mary Claire Tuohy, Elizabeth M C Hillman, Randolph Marshall, Dritan Agalliu

Faculty, Staff and Student Publications

Stroke is a devastating cause of global morbidity and mortality. Ischemic brain injury triggers a profound local and systemic immune response that participates in stroke pathophysiology. In turn, this immune response has emerged as a potential therapeutic target. In order to maximize its therapeutic potential, it is critical to understand how the immune response to ischemic brain injury is affected by age - the strongest non-modifiable risk factor for stroke. The development of multi-omics and single-cell technologies has provided a more comprehensive characterization of transcriptional and cellular changes that occur during aging. In this review, we summarize recent advances in …

Safety And Tolerability Of Ser-109 As An Investigational Microbiome Therapeutic In Adults With Recurrent Clostridioides Difficile Infection: A Phase 3, Open-Label, Single-Arm Trial, Matthew D Sims, Sahil Khanna, Paul Feuerstadt, Thomas J Louie, Colleen R Kelly, Edward S Huang, Elizabeth L Hohmann, Elaine E L Wang, Caterina Oneto, Stuart H Cohen, Charles S Berenson, Louis Korman, Christine Lee, Bret Lashner, Colleen S Kraft, Mayur Ramesh, Michael Silverman, Darrell S Pardi, Ananya De, Asli Memisoglu, David A Lombardi, Brooke R Hasson, Barbara H Mcgovern, Lisa Von Moltke

Faculty, Staff and Student Publications

IMPORTANCE: A safe and effective treatment for recurrent Clostridioides difficile infection (CDI) is urgently needed. Antibiotics kill toxin-producing bacteria but do not repair the disrupted microbiome, which promotes spore germination and infection recurrence.

OBJECTIVES: To evaluate the safety and rate of CDI recurrence after administration of investigational microbiome therapeutic SER-109 through 24 weeks.

DESIGN, SETTING, AND PARTICIPANTS: This phase 3, single-arm, open-label trial (ECOSPOR IV) was conducted at 72 US and Canadian outpatient sites from October 2017 to April 2022. Adults aged 18 years or older with recurrent CDI were enrolled in 2 cohorts: (1) rollover patients from the ECOSPOR …

Hyaluronan In The Pathogenesis Of Acute And Post-Acute Covid-19 Infection, Henry W Barnes, Sally Demirdjian, Naomi L Haddock, Gernot Kaber, Hunter A Martinez, Nadine Nagy, Harry Karmouty-Quintana, Paul L Bollyky

Faculty, Staff and Student Publications

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recently emerged as the cause of a global pandemic. Infection with SARS-CoV-2 can result in COVID-19 with both acute and chronic disease manifestations that continue to impact many patients long after the resolution of viral replication. There is therefore great interest in understanding the host factors that contribute to COVID-19 pathogenesis. In this review, we address the role of hyaluronan (HA), an extracellular matrix polymer with roles in inflammation and cellular metabolism, in COVID-19 and critically evaluate the hypothesis that HA promotes COVID-19 pathogenesis. We first provide a brief overview of COVID-19 infection. …

State-Of-The-Art In Carbides/Carbon Composites For Electromagnetic Wave Absorption, Jingjing Huang, Hydia Puente, Nancy E Wareing, Minghua Wu, Maureen D Mayes, Harry Karmouty-Quintana, Shervin Assassi, Tingting W Mills

Faculty, Staff and Student Publications

Fibrosis of the skin and internal organs is a hallmark of systemic sclerosis (SSc). Although the pathogenesis of SSc is poorly understood, increasing evidence suggests that interleukins (IL)-4 and - 13 contribute to the pathogenesis of skin fibrosis by promoting collagen production and myofibroblast differentiation. Signal transducers and activators of transcription 6 (STAT6) is one of the most important downstream transcription factors activated by both IL-4 and IL-13. However, it is not completely understood whether STAT6 plays a role during the pathogenesis of skin fibrosis in SSc. In this study, we observed increased STAT6 phosphorylation in fibrotic skin samples collected …

Broad Protective Vaccination Against Systemic Escherichia Coli With Autotransporter Antigens, Yikun Xing, Justin R Clark, James D Chang, Dylan M Chirman, Sabrina Green, Jacob J Zulk, Joseph Jelinski, Kathryn A Patras, Anthony W Maresso

Faculty, Staff and Students Publications

Extraintestinal pathogenic Escherichia coli (ExPEC) is the leading cause of adult life-threatening sepsis and urinary tract infections (UTI). The emergence and spread of multidrug-resistant (MDR) ExPEC strains result in a considerable amount of treatment failure and hospitalization costs, and contribute to the spread of drug resistance amongst the human microbiome. Thus, an effective vaccine against ExPEC would reduce morbidity and mortality and possibly decrease carriage in healthy or diseased populations. A comparative genomic analysis demonstrated a gene encoding an invasin-like protein, termed sinH, annotated as an autotransporter protein, shows high prevalence in various invasive ExPEC phylogroups, especially those associated with …

Modeling Ewing Sarcoma Lung Metastasis, Atreyi Dasgupta, Lyazat Kurenbekova, Tajhal D Patel, Kimal Rajapakshe, Gargi Ghosal, Bikesh Nirala, Cristian Coarfa, Jason Yustein

Faculty, Staff and Students Publications

Ewing Sarcoma (EwS) is the second most common malignant bone tumor in adolescents and young adults. The single-most powerful predictor of outcome in EwS is presence of metastatic burden at the time of diagnosis. Patients with metastatic Ewing Sarcoma have an abysmal 5-year survival rate of 10–25%, which has not changed over the past 30–40 years. Thus, unraveling underlying mechanisms of EwS metastasis are imperative for developing effective therapeutic measures. Investigations towards this goal are limited by the lack of reliable genetically engineered mouse models and specialized metastatic models. Using two established cell lines, A673 and TC71, we generated lung …

Early Life Reprogramming-Based Treatment Promotes Longevity, Patrizia Pessina, Bruno Di Stefano

Faculty, Staff and Students Publications

Short-term expression of Yamanaka factors early in life promotes epigenetic reprogramming and an increased healthy lifespan in a mouse model of accelerated aging.

Rates Of Antimicrobial Resistance In Helicobacter Pylori Isolates From Clinical Trial Patients Across The Us And Europe, Francis Mégraud, David Y Graham, Colin W Howden, Ernest Trevino, Alice Weissfeld, Barbara Hunt, Neila Smith, Eckhard Leifke, William D Chey

Faculty, Staff and Students Publications

INTRODUCTION: Guidelines recommend that proton pump inhibitor-based triple regimens with clarithromycin not be used for Helicobacter pylori infection in areas where clarithromycin resistance is ≥15%, or in patients with prior macrolide use. Up-to-date information on local resistance patterns is limited, especially in the US. Here, we report resistance rates to antibiotics commonly used to treat H. pylori from a large study conducted in the US and Europe (pHalcon-HP).

METHODS: Gastric mucosal biopsies were collected from adult participants with H. pylori infection during screening. Minimum inhibitory concentrations were determined via agar dilution for clarithromycin, amoxicillin, and metronidazole, with breakpoints ≥1 μg/mL, …

Glycolysis Regulates Kras Plasma Membrane Localization And Function Through Defined Glycosphingolipids, Junchen Liu, Ransome Van Der Hoeven, Walaa E Kattan, Jeffrey T Chang, Dina Montufar-Solis, Wei Chen, Maurice Wong, Yong Zhou, Carlito B Lebrilla, John F Hancock

Faculty, Staff and Student Publications

Oncogenic KRAS expression generates a metabolic dependency on aerobic glycolysis, known as the Warburg effect. We report an effect of increased glycolytic flux that feeds into glycosphingolipid biosynthesis and is directly linked to KRAS oncogenic function. High resolution imaging and genetic approaches show that a defined subset of outer leaflet glycosphingolipids, including GM3 and SM4, is required to maintain KRAS plasma membrane localization, with GM3 engaging in cross-bilayer coupling to maintain inner leaflet phosphatidylserine content. Thus, glycolysis is critical for KRAS plasma membrane localization and nanoscale spatial organization. Reciprocally oncogenic KRAS selectively upregulates cellular content of these same glycosphingolipids, whose …

Construction And Characterization Of Functional Ftsa Sandwich Fusions For Studies Of Ftsa Localization And Dynamics During Escherichia Coli Cell Division, Todd A Cameron, William Margolin

Faculty, Staff and Student Publications

FtsA, a homolog of actin, is essential for cell division of Escherichia coli and is widely conserved among many bacteria. FtsA helps to tether polymers of the bacterial tubulin homolog FtsZ to the cytoplasmic membrane as part of the cytokinetic Z ring. GFP fusions to FtsA have illuminated FtsA’s localization in live E. coli, but these fusions have not been fully functional and required the presence of the native FtsA. Here, we characterize “sandwich” fusions of E. coli FtsA to either mCherry or msfGFP that are functional for cell division and exhibit fluorescent rings at midcell that persist throughout …

Enhancer-Promoter Entanglement Explains Their Transcriptional Interdependence, Anil K Panigrahi, David M Lonard, Bert W O'Malley

Faculty, Staff and Students Publications

Enhancers not only activate target promoters to stimulate messenger RNA (mRNA) synthesis, but they themselves also undergo transcription to produce enhancer RNAs (eRNAs), the significance of which is not well understood. Transcription at the participating enhancer-promoter pair appears coordinated, but it is unclear why and how. Here, we employ cell-free transcription assays using constructs derived from the human GREB1 locus to demonstrate that transcription at an enhancer and its target promoter is interdependent. This interdependence is observable under conditions where direct enhancer-promoter contact (EPC) takes place. We demonstrate that transcription activation at a participating enhancer-promoter pair is dependent on i) …

Baloxavir Safety And Clinical And Virologic Outcomes In Influenza Virus-Infected Pediatric Patients By Age Group: Age-Based Pooled Analysis Of Two Pediatric Studies Conducted In Japan, Nobuo Hirotsu, Hiroki Sakaguchi, Keita Fukao, Satoshi Kojima, Pedro A Piedra, Kenji Tsuchiya, Takeki Uehara

Faculty, Staff and Students Publications

BACKGROUND: Anti-influenza treatment is important for children and is recommended in many countries. This study assessed safety, clinical, and virologic outcomes of baloxavir marboxil (baloxavir) treatment in children based on age and influenza virus type/subtype.

METHODS: This was a post hoc pooled analysis of two open-label non-controlled studies of a single weight-based oral dose of baloxavir (day 1) in influenza virus-infected Japanese patients aged < 6 years (n = 56) and ≥ 6 to < 12 years (n = 81). Safety, time to illness alleviation (TTIA), time to resolution of fever (TTRF), recurrence of influenza illness symptoms and fever (after day 4), virus titer, and outcomes by polymerase acidic protein variants at position I38 (PA/I38X) were evaluated.

RESULTS: Adverse events were reported in 39.0 and 39.5% of patients < 6 years and ≥ 6 to < 12 years, respectively. Median (95% confidence interval) TTIA was 43.2 (36.3-68.4) and 45.4 (38.9-61.0) hours, and TTRF was 32.2 (26.8-37.8) and 20.7 (19.2-23.8) hours, for patients < 6 years and ≥ 6 to < 12 years, respectively. Symptom and fever recurrence was more common in patients < 6 years with influenza B (54.5 and 50.0%, respectively) compared with older patients (0 and 25.0%, respectively). Virus titers declined (day 2) for both age groups. Transient virus titer increase and PA/I38X-variants were more common for patients < 6 years.

CONCLUSIONS: The safety and effectiveness of single-dose baloxavir were observed in children across all age groups and influenza virus types. Higher rates of fever recurrence …

A Rodent Model For Dirofilaria Immitis, Canine Heartworm: Parasite Growth, Development, And Drug Sensitivity In Nsg Mice, Jessica A. Hess, Mark L. Eberhard, Marcelo Segura-Lepe, Kathrin Grundner-Culemann, Barbara Kracher, Jeffrey Shryock, John Harrington, David Abraham

Department of Microbiology and Immunology Faculty Papers

Heartworm disease, caused by Dirofilaria immitis, remains a significant threat to canines and felines. The development of parasites resistant to macrocyclic lactones (ML) has created a significant challenge to the control of the infection. The goal of this study was to determine if mice lacking a functional immune response would be susceptible to D. immitis. Immunodeficient NSG mice were susceptible to the infection, sustaining parasites for at least 15 weeks, with infective third-stage larvae molting and developing into the late fourth-stage larvae. Proteomic analysis of host responses to the infection revealed a complex pattern of changes after infection, with at …