Digital Commons Network^™

U2af1 Is A Haplo-Essential Gene Required For Hematopoietic Cancer Cell Survival In Mice, Brian A Wadugu, Sridhar Nonavinkere Srivatsan, Amanda Heard, Michael O Alberti, Matthew Ndonwi, Jie Liu, Sarah Grieb, Joseph Bradley, Jin Shao, Tanzir Ahmed, Cara L Shirai, Ajay Khanna, Christopher A Miller, Matthew J Walter, Et Al

Open Access Publications

Somatic mutations in the spliceosome gene U2AF1 are common in patients with myelodysplastic syndromes. U2AF1 mutations that code for the most common amino acid substitutions are always heterozygous, and the retained WT allele is expressed, suggesting that mutant hematopoietic cells may require the residual WT allele to be viable. We show that hematopoiesis and RNA splicing in U2af1 heterozygous knockout mice were similar to those in control mice, but that deletion of the WT allele in U2AF1(S34F) heterozygous mutant-expressing hematopoietic cells (i.e., hemizygous mutant) was lethal. These results confirm that U2AF1 mutant hematopoietic cells are dependent on the expression of …

Biofilm Formation And Virulence Of Shigella Flexneri Are Modulated By Ph Of Gastrointestinal Tract, I-Ling Chiang, Yi Wang, Satoru Fujii, Brian D Muegge, Qiuhe Lu, Phillip I Tarr, Thaddeus S Stappenbeck

Open Access Publications

No abstract provided.

Motor Improvements Enabled By Spinal Cord Stimulation Combined With Physical Training After Spinal Cord Injury: Review Of Experimental Evidence In Animals And Humans, Ismael Seáñez, Marco Capogrosso

Open Access Publications

Electrical spinal cord stimulation (SCS) has been gaining momentum as a potential therapy for motor paralysis in consequence of spinal cord injury (SCI). Specifically, recent studies combining SCS with activity-based training have reported unprecedented improvements in motor function in people with chronic SCI that persist even without stimulation. In this work, we first provide an overview of the critical scientific advancements that have led to the current uses of SCS in neurorehabilitation: e.g. the understanding that SCS activates dormant spinal circuits below the lesion by recruiting large-to-medium diameter sensory afferents within the posterior roots. We discuss how this led to …

High Seropositivity Rate Of Neutralizing Antibodies To Astrovirus Va1 In Human Populations, Andrew B Janowski, Macee C Owen, Holly Dudley, Tomás López, Rafaela Espinosa, Memory Elvin-Lewis, Alejandro Colichon, Carlos F Arias, Peter D Burbelo, David Wang

Open Access Publications

Astroviruses are common pathogens of the human gastrointestinal tract, but they have been recently identified from cases of fatal meningoencephalitis. Astrovirus VA1 is the most frequently detected astrovirus genotype from cases of human encephalitis, but the prevalence of neutralizing antibodies to VA1 in human sera is unknown. We developed a focus reduction neutralization assay (FRNT) for VA1 and measured the seroprevalence of neutralizing antibodies from two cohorts of adult and pediatric serum samples: (i) an age-stratified cohort from St. Louis, MO, collected from 2007 to 2008 and (ii) a cohort from the Peruvian Amazonian River Basin collected in the late …

Structural Mechanism Of Sars-Cov-2 Neutralization By Two Murine Antibodies Targeting The Rbd, John M Errico, Haiyan Zhao, Rita E Chen, Zhuoming Liu, James Brett Case, Meisheng Ma, Aaron J Schmitz, Michael J Rau, James A J Fitzpatrick, Pei-Yong Shi, Michael S Diamond, Sean P J Whelan, Ali H Ellebedy, Daved H Fremont

Open Access Publications

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has necessitated the rapid development of antibody-based therapies and vaccines as countermeasures. Here, we use cryoelectron microscopy (cryo-EM) to characterize two protective anti-SARS-CoV-2 murine monoclonal antibodies (mAbs) in complex with the spike protein, revealing similarities between epitopes targeted by human and murine B cells. The more neutralizing mAb, 2B04, binds the receptor-binding motif (RBM) of the receptor-binding domain (RBD) and competes with angiotensin-converting enzyme 2 (ACE2). By contrast, 2H04 binds adjacent to the RBM and does not compete for ACE2 binding. Naturally occurring sequence variants of SARS-CoV-2 and corresponding neutralization escape …

A Novel Class Of Tmprss2 Inhibitors Potently Block Sars-Cov-2 And Mers-Cov Viral Entry And Protect Human Epithelial Lung Cells, Matthew Mahoney, Vishnu C Damalanka, Michael A Tartell, Anne E Mayer Bridwell, Jorine Voss, Partha Karmakar, Paul W Rothlauf, Cassandra E Thompson, Christina L Stallings, Sean P J Whelan, James W Janetka, Et Al

Open Access Publications

The host cell serine protease TMPRSS2 is an attractive therapeutic target for COVID-19 drug discovery. This protease activates the Spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and of other coronaviruses and is essential for viral spread in the lung. Utilizing rational structure-based drug design (SBDD) coupled to substrate specificity screening of TMPRSS2, we have discovered covalent small-molecule ketobenzothiazole (kbt) TMPRSS2 inhibitors which are structurally distinct from and have significantly improved activity over the existing known inhibitors Camostat and Nafamostat. Lead compound MM3122 (4) has an IC

Comparative Genomics Of Mycobacterium Avium Complex Reveals Signatures Of Environment-Specific Adaptation And Community Acquisition, Eric C Keen, Joohee Choi, Meghan A Wallace, Michelle Azar, Carlos R Mejia-Chew, Shail B Mehta, Thomas C Bailey, Lindsay J Caverly, Carey-Ann D Burnham, Gautam Dantas

Open Access Publications

Nontuberculous mycobacteria, including those in the Mycobacterium avium complex (MAC), constitute an increasingly urgent threat to global public health. Ubiquitous in soil and water worldwide, MAC members cause a diverse array of infections in humans and animals that are often multidrug resistant, intractable, and deadly. MAC lung disease is of particular concern and is now more prevalent than tuberculosis in many countries, including the United States. Although the clinical importance of these microorganisms continues to expand, our understanding of their genomic diversity is limited, hampering basic and translational studies alike. Here, we leveraged a unique collection of genomes to characterize …

Neutralizing Monoclonal Antibodies That Target The Spike Receptor Binding Domain Confer Fc Receptor-Independent Protection Against Sars-Cov-2 Infection In Syrian Hamsters, Wen Su, Sin Fun Sia, Aaron J Schmitz, Traci L Bricker, Tyler N Starr, Allison J Greaney, Jackson S Turner, Bassem M Mohammed, Zhuoming Liu, Ka Tim Choy, Tamarand L Darling, Astha Joshi, Ka Man Cheng, Alvina Y L Wong, Houda H Harastani, John M Nicholls, Sean P J Whelan, Jesse D Bloom, Hui-Ling Yen, Ali H Ellebedy, Adrianus C M Boon

Open Access Publications

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein is the main target for neutralizing antibodies. These antibodies can be elicited through immunization or passively transferred as therapeutics in the form of convalescent-phase sera or monoclonal antibodies (MAbs). Potently neutralizing antibodies are expected to confer protection; however, it is unclear whether weakly neutralizing antibodies contribute to protection. Also, their mechanism of action

Human Monoclonal Antibodies Against Ns1 Protein Protect Against Lethal West Nile Virus Infection, Alex W Wessel, Michael P Doyle, Taylor B Engdahl, Jessica Rodriguez, James E Crowe, Michael S Diamond

Open Access Publications

Envelope protein-targeted vaccines for flaviviruses are limited by concerns of antibody-dependent enhancement (ADE) of infections. Nonstructural protein 1 (NS1) provides an alternative vaccine target that avoids this risk since this protein is absent from the virion. Beyond its intracellular role in virus replication, extracellular forms of NS1 function in immune modulation and are recognized by host-derived antibodies. The rational design of NS1-based vaccines requires an extensive understanding of the antigenic sites on NS1, especially those targeted by protective antibodies. Here, we isolated human monoclonal antibodies (MAbs) from individuals previously naturally infected with WNV, mapped their epitopes using structure-guided mutagenesis, and …

Functionality Of The Putative Surface Glycoproteins Of The Wuhan Spiny Eel Influenza Virus, Guha Asthagiri Arunkumar, Disha Bhavsar, Tiehai Li, Shirin Strohmeier, Veronika Chromikova, Fatima Amanat, Mehman Bunyatov, Patrick C Wilson, Ali H Ellebedy, Geert-Jan Boons, Viviana Simon, Robert P De Vries, Florian Krammer

Open Access Publications

A panel of influenza virus-like sequences were recently documented in fish and amphibians. Of these, the Wuhan spiny eel influenza virus (WSEIV) was found to phylogenetically cluster with influenza B viruses as a sister clade. Influenza B viruses have been documented to circulate only in humans, with certain virus isolates found in harbor seals. It is therefore interesting that a similar virus was potentially found in fish. Here we characterize the putative hemagglutinin (HA) and neuraminidase (NA) surface glycoproteins of the WSEIV. Functionally, we show that the WSEIV NA-like protein has sialidase activity comparable to B/Malaysia/2506/2004 influenza B virus NA, …

Comparison Of 2-Year Outcomes With Car T Cells (Zuma-1) Vs Salvage Chemotherapy In Refractory Large B-Cell Lymphoma, Sattva S. Neelapu, Nancy L. Bartlett, Et Al

Open Access Publications

No abstract provided.

Brief Electrical Stimulation Accelerates Axon Regeneration And Promotes Recovery Following Nerve Transection And Repair In Mice, Junichi Sayanagi, Jesús A Acevedo-Cintrón, Deng Pan, Lauren Schellhardt, Daniel A Hunter, Alison K Snyder-Warwick, Susan E Mackinnon, Matthew D Wood

Open Access Publications

BACKGROUND: Clinical outcomes following nerve injury repair can be inadequate. Pulsed-current electrical stimulation (ES) is a therapeutic method that facilitates functional recovery by accelerating axon regeneration. However, current clinical ES protocols involve the application of ES for 60 minutes during surgery, which can increase operative complexity and time. Shorter ES protocols could be a strategy to facilitate broader clinical adoption. The purpose of the present study was to determine if a 10-minute ES protocol could improve outcomes.

METHODS: C57BL/6J mice were randomized to 3 groups: no ES, 10 minutes of ES, and 60 minutes of ES. In all groups, the …

Sirtuin 1 Mediates Protection Against Delayed Cerebral Ischemia In Subarachnoid Hemorrhage In Response To Hypoxic Postconditioning, Deepti Diwan, Ananth K Vellimana, Diane J Aum, Julian Clarke, James W Nelson, Molly Lawrence, Byung Hee Han, Jeffrey M Gidday, Gregory J Zipfel

Open Access Publications

Background Many therapies designed to prevent delayed cerebral ischemia (DCI) and improve neurological outcome in aneurysmal subarachnoid hemorrhage (SAH) have failed, likely because of targeting only one element of what has proven to be a multifactorial disease. We previously demonstrated that initiating hypoxic conditioning before SAH (hypoxic preconditioning) provides powerful protection against DCI. Here, we expanded upon these findings to determine whether hypoxic conditioning delivered at clinically relevant time points after SAH (hypoxic postconditioning) provides similarly robust DCI protection. Methods and Results In this study, we found that hypoxic postconditioning (8% O

Neurotoxins Subvert The Allosteric Activation Mechanism Of Sarm1 To Induce Neuronal Loss, Tong Wu, Jian Zhu, Amy Strickland, Kwang Woo Ko, Yo Sasaki, Caitlin B Dingwall, Yurie Yamada, Matthew D Figley, Xianrong Mao, Alicia Neiner, A Joseph Bloom, Aaron Diantonio, Jeffrey Milbrandt

Open Access Publications

SARM1 is an inducible TIR-domain NAD

Nrf2 Promotes Urothelial Cell Response To Bacterial Infection By Regulating Reactive Oxygen Species And Rab27b Expression, Chetanchandra S Joshi, Amy Mora, Paul A Felder, Indira U Mysorekar

Open Access Publications

Uropathogenic Escherichia coli (UPEC) cause urinary tract infections (UTIs) by invading urothelial cells. In response, the host mounts an inflammatory response to expel bacteria. Here, we show that the NF-E2-related factor 2 (NRF2) pathway is activated in response to UPEC-triggered reactive oxygen species (ROS) production. We demonstrate the molecular sequence of events wherein NRF2 activation in urothelial cells reduces ROS production, inflammation, and cell death, promotes UPEC expulsion, and reduces the bacterial load. In contrast, loss of NRF2 leads to increased ROS production, bacterial burden, and inflammation, both in vitro and in vivo. NRF2 promotes UPEC expulsion by regulating transcription …

Alternative Pre-Mrna Splicing Of The Mu Opioid Receptor Gene, Oprm1: Insight Into Complex Mu Opioid Actions, Shan Liu, Wen-Jia Kang, Anna Abrimian, Jin Xu, Luca Cartegni, Susruta Majumdar, Patrick Hesketh, Alex Bekker, Ying-Xian Pan

Open Access Publications

Most opioid analgesics used clinically, including morphine and fentanyl, as well as the recreational drug heroin, act primarily through the mu opioid receptor, a class A Rhodopsin-like G protein-coupled receptor (GPCR). The single-copy mu opioid receptor gene,

Aducanumab For Alzheimer Disease: The Amyloid Hypothesis Moves From Bench To Bedside, Erik S. Musiek, Teresa Gomez-Isla, David M Holtzman

Open Access Publications

No abstract provided.

Cullin4 E3 Ubiquitin Ligases Regulate Male Gonocyte Migration, Proliferation And Blood-Testis Barrier Homeostasis, Yan Yin, Liming Zhu, Qiufang Li, Pengbo Zhou, Liang Ma

Open Access Publications

Ubiquitination, an essential posttranslational modification, plays fundamental roles during mammalian spermatogenesis. We previously reported the requirement of two Cullin 4 ubiquitin ligase family genes, Cullin 4a (

Nuclear-Localized Human Respiratory Syncytial Virus Ns1 Protein Modulates Host Gene Transcription, Jingjing Pei, Nina R Beri, Angela J Zou, Philipp Hubel, Hannah K Dorando, Valter Bergant, Rebecca D Andrews, Jiehong Pan, Jared M Andrews, Kathleen C F Sheehan, Andreas Pichlmair, Gaya K Amarasinghe, Steven L Brody, Jacqueline E Payton, Daisy W Leung

Open Access Publications

Human respiratory syncytial virus (RSV) is a common cause of lower respiratory tract infections in the pediatric, elderly, and immunocompromised individuals. RSV non-structural protein NS1 is a known cytosolic immune antagonist, but how NS1 modulates host responses remains poorly defined. Here, we observe NS1 partitioning into the nucleus of RSV-infected cells, including the human airway epithelium. Nuclear NS1 coimmunoprecipitates with Mediator complex and is chromatin associated. Chromatin-immunoprecipitation demonstrates enrichment of NS1 that overlaps Mediator and transcription factor binding within the promoters and enhancers of differentially expressed genes during RSV infection. Mutation of the NS1 C-terminal helix reduces NS1 impact on …

Braf Mutations May Identify A Clinically Distinct Subset Of Glioblastoma, Samantha N Mcnulty, Katherine E Schwetye, Cole Ferguson, Chad E Storer, George Ansstas, Albert H Kim, David H Gutmann, Joshua B Rubin, Richard D Head, Sonika Dahiya

Open Access Publications

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. Prior studies examining the mutational landscape of GBM revealed recurrent alterations in genes that regulate the same growth control pathways. To this regard, ~ 40% of GBM harbor EGFR alterations, whereas BRAF variants are rare. Existing data suggests that gain-of-function mutations in these genes are mutually exclusive. This study was designed to explore the clinical, pathological, and molecular differences between EGFR- and BRAF-mutated GBM. We reviewed retrospective clinical data from 89 GBM patients referred for molecular testing between November 2012 and December 2015. Differences in tumor mutational profile, …

Rn7sk Small Nuclear Rna Controls Bidirectional Transcription Of Highly Expressed Gene Pairs In Skin, Roberto Bandiera, Rebecca E Wagner, Thiago Britto-Borges, Christoph Dieterich, Sabine Dietmann, Susanne Bornelöv, Michaela Frye

Open Access Publications

Pausing of RNA polymerase II (Pol II) close to promoters is a common regulatory step in RNA synthesis, and is coordinated by a ribonucleoprotein complex scaffolded by the noncoding RNA RN7SK. The function of RN7SK-regulated gene transcription in adult tissue homoeostasis is currently unknown. Here, we deplete RN7SK during mouse and human epidermal stem cell differentiation. Unexpectedly, loss of this small nuclear RNA specifically reduces transcription of numerous cell cycle regulators leading to cell cycle exit and differentiation. Mechanistically, we show that RN7SK is required for efficient transcription of highly expressed gene pairs with bidirectional promoters, which in the epidermis …

Inhibition Of The Nlrp3 Inflammasome Improves Lifespan In Animal Murine Model Of Hutchinson-Gilford Progeria, Alvaro González-Dominguez, Raúl Montañez, Beatriz Castejón-Vega, Jéssica Nuñez-Vasco, Débora Lendines-Cordero, Chun Wang, Gabriel Mbalaviele, José M Navarro-Pando, Elísabet Alcocer-Gómez, Mario D Cordero

Open Access Publications

Inflammation is a hallmark of aging and accelerated aging syndromes such as Hutchinson-Gilford progeria syndrome (HGPS). In this study, we present evidence of increased expression of the components of the NLRP3 inflammasome pathway in HGPS skin fibroblasts, an outcome that was associated with morphological changes of the nuclei of the cells. Lymphoblasts from HGPS patients also showed increased basal levels of NLRP3 and caspase 1. Consistent with these results, the expression of caspase 1 and Nlrp3, but not of the other inflammasome receptors was higher in the heart and liver of Zmpste24

Role Of Enhancers In Development And Diseases, Shailendra S Maurya

Open Access Publications

Enhancers are cis-regulatory elements containing short DNA sequences that serve as binding sites for pioneer/regulatory transcription factors, thus orchestrating the regulation of genes critical for lineage determination. The activity of enhancer elements is believed to be determined by transcription factor binding, thus determining the cell state identity during development. Precise spatio-temporal control of the transcriptome during lineage specification requires the coordinated binding of lineage-specific transcription factors to enhancers. Thus, enhancers are the primary determinants of cell identity. Numerous studies have explored the role and mechanism of enhancers during development and disease, and various basic questions related to the functions and …

A Transcriptomic And Epigenomic Cell Atlas Of The Mouse Primary Motor Cortex, Zizhen Yao, Hanqing Liu, Fangming Xie, Stephan Fischer, Xinxin Wang, Et Al

Open Access Publications

Single-cell transcriptomics can provide quantitative molecular signatures for large, unbiased samples of the diverse cell types in the brain

Structure Of Venezuelan Equine Encephalitis Virus In Complex With The Ldlrad3 Receptor, Katherine Basore, Hongming Ma, Natasha M Kafai, Samantha Mackin, Arthur S Kim, Christopher A Nelson, Michael S Diamond, Daved H Fremont

Open Access Publications

LDLRAD3 is a recently defined attachment and entry receptor for Venezuelan equine encephalitis virus (VEEV)

X-Treme Loss Of Sequence Diversity Linked To Neo-X Chromosomes In Filarial Nematodes, John Mattick, Ramakrishna Rao, Et Al

Open Access Publications

The sequence diversity of natural and laboratory populations of Brugia pahangi and Brugia malayi was assessed with Illumina resequencing followed by mapping in order to identify single nucleotide variants and insertions/deletions. In natural and laboratory Brugia populations, there is a lack of sequence diversity on chromosome X relative to the autosomes (πX/πA = 0.2), which is lower than the expected (πX/πA = 0.75). A reduction in diversity is also observed in other filarial nematodes with neo-X chromosome fusions in the genera Onchocerca and Wuchereria, but not those without neo-X chromosome fusions in the genera Loa and Dirofilaria. In the species …

Cortical Feedback And Gating In Odor Discrimination And Generalization, Gaia Tavoni, David E. Chen Kersen, Vijay Balasubramanian

Open Access Publications

A central question in neuroscience is how context changes perception. In the olfactory system, for example, experiments show that task demands can drive divergence and convergence of cortical odor responses, likely underpinning olfactory discrimination and generalization. Here, we propose a simple statistical mechanism for this effect based on unstructured feedback from the central brain to the olfactory bulb, which represents the context associated with an odor, and sufficiently selective cortical gating of sensory inputs. Strikingly, the model predicts that both convergence and divergence of cortical odor patterns should increase when odors are initially more similar, an effect reported in recent …

Diffusion-Weighted Imaging Reveals Distinct Patterns Of Cytotoxic Edema In Patients With Subdural Hematomas, David Robinson, Natalie Kreitzer, Laura B Ngwenya, Opeolu Adeoye, Daniel Woo, Jed Hartings, Brandon Foreman

Open Access Publications

Subdural hematomas (SDHs) are increasingly common and can cause ischemic brain injury. Previous work has suggested that this is driven largely by vascular compression from herniation, although this work was done before the era of magnetic resonance imaging (MRI). We thus sought to study SDH-related ischemic brain injury by looking at patterns of cytotoxic edema on diffusion-weighted MRI. To do so, we identified all SDH patients at a single institution from 2015 to 2019 who received an MRI within 2 weeks of presentation. We reviewed all MRIs for evidence of restricted diffusion consistent with cytotoxic edema. Cases were excluded if …

Augmented Reality In Spinal Surgery: Highlights From Augmented Reality Lectures At The Emerging Technologies Annual Meetings, Syed-Abdullah Uddin, George Hanna, Lindsey Ross, Camilo Molina, Timur Urakov, Patrick Johnson, Terrence Kim, Doniel Drazin

Open Access Publications

Introduction Augmented reality (AR) is an advanced technology and emerging field that has been adopted into spine surgery to enhance care and outcomes. AR superimposes a three-dimensional computer-generated image over the normal anatomy of interest in order to facilitate visualization of deep structures without the ability to directly see them. Objective To summarize the latest literature and highlight AR from the annual "Spinal Navigation, Emerging Technologies and Systems Integration" meeting lectures presented by the Seattle Science Foundation (SSF) on the development and use of augmented reality in spinal surgery. Methods We performed a comprehensive literature review from 2016 to 2020 …

Recognizing The Vulnerable: Perspectives, Attitudes, And Interests Of Women With Uterine Factor Infertility Towards Uterus Allotransplantation, Helen Xun, Darya Fadavi, Halley Darrach, Nicole Fischer, Pooja Yesantharao, Franca Kraenzlin, Amanda Nickles Fader, James H. Segars, Justin M. Sacks

Open Access Publications

BACKGROUND: Uterine allotransplantation (UTx) is a novel therapy to allow women with uterine factor infertility (UFI) to bear their own children. To date, over 60 UTx have been performed, resulting in 15 live births. Our study investigates the attitudes, perspectives, and interests of women with UFI towards UTx.

METHODS: Anonymous questionnaires were distributed electronically to women diagnosed with UFI at Johns Hopkins Hospital between the years 2003 and 2018.

RESULTS: Thirty-one women with UFI were identified, resulting in 10 completed surveys. The average age was 31.7 ± 6.31 years, and the average age of diagnosis was 20 years (range 14-31); …