Publications by authors named "Mark T Heise"

80 Publications

Targeting Chikungunya Virus Replication by Benzoannulene Inhibitors.

J Med Chem 2021 Apr 9. Epub 2021 Apr 9.

Drug Discovery Division, Southern Research, 2000 Ninth Avenue South, Birmingham, Alabama 35205, United States.

A benzo[6]annulene, 4-(-butyl)--(3-methoxy-5,6,7,8-tetrahydronaphthalen-2-yl) benzamide (), was identified as an inhibitor against Chikungunya virus (CHIKV) with antiviral activity EC = 1.45 μM and viral titer reduction (VTR) of 2.5 log at 10 μM with no observed cytotoxicity (CC = 169 μM) in normal human dermal fibroblast cells. Chemistry efforts to improve potency, efficacy, and drug-like properties of resulted in a novel lead compound , which possessed excellent cellular antiviral activity (EC = 270 nM and VTR of 4.5 log at 10 μM) and improved liver microsomal stability. CHIKV resistance to an analog of , compound , tracked to a mutation in the nsP3 macrodomain. Further mechanism of action studies showed compounds working through inhibition of human dihydroorotate dehydrogenase in addition to CHIKV nsP3 macrodomain. Moderate efficacy was observed in an CHIKV challenge mouse model for compound as viral replication was rescued from the pyrimidine salvage pathway.
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http://dx.doi.org/10.1021/acs.jmedchem.0c02183DOI Listing
April 2021

Non-replicating adenovirus based Mayaro virus vaccine elicits protective immune responses and cross protects against other alphaviruses.

PLoS Negl Trop Dis 2021 Apr 1;15(4):e0009308. Epub 2021 Apr 1.

Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, Oregon, United States of America.

Mayaro virus (MAYV) is an alphavirus endemic to South and Central America associated with sporadic outbreaks in humans. MAYV infection causes severe joint and muscle pain that can persist for weeks to months. Currently, there are no approved vaccines or therapeutics to prevent MAYV infection or treat the debilitating musculoskeletal inflammatory disease. In the current study, a prophylactic MAYV vaccine expressing the complete viral structural polyprotein was developed based on a non-replicating human adenovirus V (AdV) platform. Vaccination with AdV-MAYV elicited potent neutralizing antibodies that protected WT mice against MAYV challenge by preventing viremia, reducing viral dissemination to tissues and mitigating viral disease. The vaccine also prevented viral-mediated demise in IFN⍺R1-/- mice. Passive transfer of immune serum from vaccinated animals similarly prevented infection and disease in WT mice as well as virus-induced demise of IFN⍺R1-/- mice, indicating that antiviral antibodies are protective. Immunization with AdV-MAYV also generated cross-neutralizing antibodies against two related arthritogenic alphaviruses-chikungunya and Una viruses. These cross-neutralizing antibodies were protective against lethal infection in IFN⍺R1-/- mice following challenge with these heterotypic alphaviruses. These results indicate AdV-MAYV elicits protective immune responses with substantial cross-reactivity and protective efficacy against other arthritogenic alphaviruses. Our findings also highlight the potential for development of a multi-virus targeting vaccine against alphaviruses with endemic and epidemic potential in the Americas.
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http://dx.doi.org/10.1371/journal.pntd.0009308DOI Listing
April 2021

Critical ACE2 Determinants of SARS-CoV-2 and Group 2B Coronavirus Infection and Replication.

mBio 2021 03 16;12(2). Epub 2021 Mar 16.

Department of Microbiology & Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA

The angiotensin-converting enzyme 2 (ACE2) receptor is a major severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) host range determinant, and understanding SARS-CoV-2-ACE2 interactions will provide important insights into COVID-19 pathogenesis and animal model development. SARS-CoV-2 cannot infect mice due to incompatibility between its receptor binding domain and the murine ACE2 receptor. Through molecular modeling and empirical validation, we identified 5 key amino acid differences between murine and human ACE2 that mediate SARS-CoV-2 infection, generating a chimeric humanized murine ACE2. Additionally, we examined the ability of the humanized murine ACE2 receptor to permit infection by an additional preemergent group 2B coronavirus, WIV-1, providing evidence for the potential pan-virus capabilities of this chimeric receptor. Finally, we predicted the ability of these determinants to inform host range identification of preemergent coronaviruses by evaluating hot spot contacts between SARS-CoV-2 and additional potential host receptors. Our results identify residue determinants that mediate coronavirus receptor usage and host range for application in SARS-CoV-2 and emerging coronavirus animal model development. SARS-CoV-2 (the causative agent of COVID-19) is a major public health threat and one of two related coronaviruses that have caused epidemics in modern history. A method of screening potential infectible hosts for preemergent and future emergent coronaviruses would aid in mounting rapid response and intervention strategies during future emergence events. Here, we evaluated determinants of SARS-CoV-2 receptor interactions, identifying key changes that enable or prevent infection. The analysis detailed in this study will aid in the development of model systems to screen emergent coronaviruses as well as treatments to counteract infections.
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http://dx.doi.org/10.1128/mBio.03149-20DOI Listing
March 2021

Highly dampened blood transcriptome response in HIV patients after influenza infection.

Sci Rep 2021 Feb 24;11(1):4465. Epub 2021 Feb 24.

Department of Infection Genetics, Helmholtz Centre for Infection Research, Brunswick, Germany.

Respiratory viral (RV) infections represent a major threat for human health worldwide. Persons with HIV (PWH) have a compromised immune response and are thought to be at higher risk for severe RV disease. However, very little is known about the host immune response to RV infection in PWH. Here, we investigated gene expression changes in the peripheral blood of PWH co-infected with RV. Only very few differentially expressed genes could be detected between PWH with and without RV infection, suggesting that the immune response to RV in PWH is strongly dampened. Our data provides important insights into the host response to RV infections in HIV patients.
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http://dx.doi.org/10.1038/s41598-021-83876-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7904929PMC
February 2021

Baseline T cell immune phenotypes predict virologic and disease control upon SARS-CoV infection in Collaborative Cross mice.

PLoS Pathog 2021 01 29;17(1):e1009287. Epub 2021 Jan 29.

Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, Unites States of America.

The COVID-19 pandemic has revealed that infection with SARS-CoV-2 can result in a wide range of clinical outcomes in humans. An incomplete understanding of immune correlates of protection represents a major barrier to the design of vaccines and therapeutic approaches to prevent infection or limit disease. This deficit is largely due to the lack of prospectively collected, pre-infection samples from individuals that go on to become infected with SARS-CoV-2. Here, we utilized data from genetically diverse Collaborative Cross (CC) mice infected with SARS-CoV to determine whether baseline T cell signatures are associated with a lack of viral control and severe disease upon infection. SARS-CoV infection of CC mice results in a variety of viral load trajectories and disease outcomes. Overall, a dysregulated, pro-inflammatory signature of circulating T cells at baseline was associated with severe disease upon infection. Our study serves as proof of concept that circulating T cell signatures at baseline can predict clinical and virologic outcomes upon SARS-CoV infection. Identification of basal immune predictors in humans could allow for identification of individuals at highest risk of severe clinical and virologic outcomes upon infection, who may thus most benefit from available clinical interventions to restrict infection and disease.
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http://dx.doi.org/10.1371/journal.ppat.1009287DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7875398PMC
January 2021

Vaccine formulations in clinical development for the prevention of severe acute respiratory syndrome coronavirus 2 infection.

Adv Drug Deliv Rev 2021 02 13;169:168-189. Epub 2020 Dec 13.

Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, USA; Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, USA; Department of Microbiology and Immunology, UNC School of Medicine, University of North Carolina, Chapel Hill, NC, USA. Electronic address:

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to an unprecedented effort toward the development of an effective and safe vaccine. Aided by extensive research efforts into characterizing and developing countermeasures towards prior coronavirus epidemics, as well as recent developments of diverse vaccine platform technologies, hundreds of vaccine candidates using dozens of delivery vehicles and routes have been proposed and evaluated preclinically. A high demand coupled with massive effort from researchers has led to the advancement of at least 31 candidate vaccines in clinical trials, many using platforms that have never before been approved for use in humans. This review will address the approach and requirements for a successful vaccine against SARS-CoV-2, the background of the myriad of vaccine platforms currently in clinical trials for COVID-19 prevention, and a summary of the present results of those trials. It concludes with a perspective on formulation problems which remain to be addressed in COVID-19 vaccine development and antigens or adjuvants which may be worth further investigation.
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http://dx.doi.org/10.1016/j.addr.2020.12.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7733686PMC
February 2021

Content and Performance of the MiniMUGA Genotyping Array: A New Tool To Improve Rigor and Reproducibility in Mouse Research.

Genetics 2020 12 16;216(4):905-930. Epub 2020 Oct 16.

Department of Genetics, University of North Carolina, Chapel Hill, North Carolina 27599.

The laboratory mouse is the most widely used animal model for biomedical research, due in part to its well-annotated genome, wealth of genetic resources, and the ability to precisely manipulate its genome. Despite the importance of genetics for mouse research, genetic quality control (QC) is not standardized, in part due to the lack of cost-effective, informative, and robust platforms. Genotyping arrays are standard tools for mouse research and remain an attractive alternative even in the era of high-throughput whole-genome sequencing. Here, we describe the content and performance of a new iteration of the Mouse Universal Genotyping Array (MUGA), MiniMUGA, an array-based genetic QC platform with over 11,000 probes. In addition to robust discrimination between most classical and wild-derived laboratory strains, MiniMUGA was designed to contain features not available in other platforms: (1) chromosomal sex determination, (2) discrimination between substrains from multiple commercial vendors, (3) diagnostic SNPs for popular laboratory strains, (4) detection of constructs used in genetically engineered mice, and (5) an easy-to-interpret report summarizing these results. In-depth annotation of all probes should facilitate custom analyses by individual researchers. To determine the performance of MiniMUGA, we genotyped 6899 samples from a wide variety of genetic backgrounds. The performance of MiniMUGA compares favorably with three previous iterations of the MUGA family of arrays, both in discrimination capabilities and robustness. We have generated publicly available consensus genotypes for 241 inbred strains including classical, wild-derived, and recombinant inbred lines. Here, we also report the detection of a substantial number of O and individuals across a variety of sample types, new markers that expand the utility of reduced complexity crosses to genetic backgrounds other than C57BL/6, and the robust detection of 17 genetic constructs. We provide preliminary evidence that the array can be used to identify both partial sex chromosome duplication and mosaicism, and that diagnostic SNPs can be used to determine how long inbred mice have been bred independently from the relevant main stock. We conclude that MiniMUGA is a valuable platform for genetic QC, and an important new tool to increase the rigor and reproducibility of mouse research.
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http://dx.doi.org/10.1534/genetics.120.303596DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7768238PMC
December 2020

Using SHAPE-MaP To Model RNA Secondary Structure and Identify 3'UTR Variation in Chikungunya Virus.

J Virol 2020 11 23;94(24). Epub 2020 Nov 23.

Department of Microbiology and Immunology, UNC-Chapel Hill, Chapel Hill, North Carolina, USA

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus associated with debilitating arthralgia in humans. RNA secondary structure in the viral genome plays an important role in the lifecycle of alphaviruses; however, the specific role of RNA structure in regulating CHIKV replication is poorly understood. Our previous studies found little conservation in RNA secondary structure between alphaviruses, and this structural divergence creates unique functional structures in specific alphavirus genomes. Therefore, to understand the impact of RNA structure on CHIKV biology, we used SHAPE-MaP to inform the modeling of RNA secondary structure throughout the genome of a CHIKV isolate from the 2013 Caribbean outbreak. We then analyzed regions of the genome with high levels of structural specificity to identify potentially functional RNA secondary structures and identified 23 regions within the CHIKV genome with higher than average structural stability, including four previously identified, functionally important CHIKV RNA structures. We also analyzed the RNA flexibility and secondary structures of multiple 3'UTR variants of CHIKV that are known to affect virus replication in mosquito cells. This analysis found several novel RNA structures within these 3'UTR variants. A duplication in the 3'UTR that enhances viral replication in mosquito cells led to an overall increase in the amount of unstructured RNA in the 3'UTR. This analysis demonstrates that the CHIKV genome contains a number of unique, specific RNA secondary structures and provides a strategy for testing these secondary structures for functional importance in CHIKV replication and pathogenesis. Chikungunya virus (CHIKV) is a mosquito-borne RNA virus that causes febrile illness and debilitating arthralgia in humans. CHIKV causes explosive outbreaks but there are no approved therapies to treat or prevent CHIKV infection. The CHIKV genome contains functional RNA secondary structures that are essential for proper virus replication. Since RNA secondary structures have only been defined for a small portion of the CHIKV genome, we used a chemical probing method to define the RNA secondary structures of CHIKV genomic RNA. We identified 23 highly specific structured regions of the genome, and confirmed the functional importance of one structure using mutagenesis. Furthermore, we defined the RNA secondary structure of three CHIKV 3'UTR variants that differ in their ability to replicate in mosquito cells. Our study highlights the complexity of the CHIKV genome and describes new systems for designing compensatory mutations to test the functional relevance of viral RNA secondary structures.
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http://dx.doi.org/10.1128/JVI.00701-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7925192PMC
November 2020

Baseline T cell immune phenotypes predict virologic and disease control upon SARS-CoV infection.

bioRxiv 2020 Sep 21. Epub 2020 Sep 21.

Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA.

The COVID-19 pandemic has revealed that infection with SARS-CoV-2 can result in a wide range of clinical outcomes in humans, from asymptomatic or mild disease to severe disease that can require mechanical ventilation. An incomplete understanding of immune correlates of protection represents a major barrier to the design of vaccines and therapeutic approaches to prevent infection or limit disease. This deficit is largely due to the lack of prospectively collected, pre-infection samples from indiviuals that go on to become infected with SARS-CoV-2. Here, we utilized data from a screen of genetically diverse mice from the Collaborative Cross (CC) infected with SARS-CoV to determine whether circulating baseline T cell signatures are associated with a lack of viral control and severe disease upon infection. SARS-CoV infection of CC mice results in a variety of viral load trajectories and disease outcomes. Further, early control of virus in the lung correlates with an increased abundance of activated CD4 and CD8 T cells and regulatory T cells prior to infections across strains. A basal propensity of T cells to express IFNg and IL17 over TNFa also correlated with early viral control. Overall, a dysregulated, pro-inflammatory signature of circulating T cells at baseline was associated with severe disease upon infection. While future studies of human samples prior to infection with SARS-CoV-2 are required, our studies in mice with SARS-CoV serve as proof of concept that circulating T cell signatures at baseline can predict clinical and virologic outcomes upon SARS-CoV infection. Identification of basal immune predictors in humans could allow for identification of individuals at highest risk of severe clinical and virologic outcomes upon infection, who may thus most benefit from available clinical interventions to restrict infection and disease.

Summary: We used a screen of genetically diverse mice from the Collaborative Cross infected with mouse-adapted SARS-CoV in combination with comprehensive pre-infection immunophenotyping to identify baseline circulating immune correlates of severe virologic and clinical outcomes upon SARS-CoV infection.
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http://dx.doi.org/10.1101/2020.09.21.306837DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7523117PMC
September 2020

Immunopathogenesis of alphaviruses.

Adv Virus Res 2020 8;107:315-382. Epub 2020 Jul 8.

Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States. Electronic address:

Alphaviruses, members of the enveloped, positive-sense, single-stranded RNA Togaviridae family, represent a reemerging public health threat as mosquito vectors expand into new geographic territories. The Old World alphaviruses, which include chikungunya virus, Ross River virus, and Sindbis virus, tend to cause a clinical syndrome characterized by fever, rash, and arthritis, whereas the New World alphaviruses, which consist of Venezuelan equine encephalitis virus, eastern equine encephalitis virus, and western equine encephalitis virus, induce encephalomyelitis. Following recovery from the acute phase of infection, many patients are left with debilitating persistent joint and neurological complications that can last for years. Clues from human cases and studies using animal models strongly suggest that much of the disease and pathology induced by alphavirus infection, particularly atypical and chronic manifestations, is mediated by the immune system rather than directly by the virus. This review discusses the current understanding of the immunopathogenesis of the arthritogenic and neurotropic alphaviruses accumulated through both natural infection of humans and experimental infection of animals, particularly mice. As treatment following alphavirus infection is currently limited to supportive care, understanding the contribution of the immune system to the disease process is critical to developing safe and effective therapies.
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http://dx.doi.org/10.1016/bs.aivir.2020.06.002DOI Listing
April 2021

Comparative analysis of coronavirus genomic RNA structure reveals conservation in SARS-like coronaviruses.

bioRxiv 2020 Jun 16. Epub 2020 Jun 16.

Coronaviruses, including SARS-CoV-2 the etiological agent of COVID-19 disease, have caused multiple epidemic and pandemic outbreaks in the past 20 years . With no vaccines, and only recently developed antiviral therapeutics, we are ill equipped to handle coronavirus outbreaks . A better understanding of the molecular mechanisms that regulate coronavirus replication and pathogenesis is needed to guide the development of new antiviral therapeutics and vaccines. RNA secondary structures play critical roles in multiple aspects of coronavirus replication, but the extent and conservation of RNA secondary structure across coronavirus genomes is unknown . Here, we define highly structured RNA regions throughout the MERS-CoV, SARS-CoV, and SARS-CoV-2 genomes. We find that highly stable RNA structures are pervasive throughout coronavirus genomes, and are conserved between the SARS-like CoV. Our data suggests that selective pressure helps preserve RNA secondary structure in coronavirus genomes, suggesting that these structures may play important roles in virus replication and pathogenesis. Thus, disruption of conserved RNA secondary structures could be a novel strategy for the generation of attenuated SARS-CoV-2 vaccines for use against the current COVID-19 pandemic.
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http://dx.doi.org/10.1101/2020.06.15.153197DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7310623PMC
June 2020

Complex Genetic Architecture Underlies Regulation of Influenza-A-Virus-Specific Antibody Responses in the Collaborative Cross.

Cell Rep 2020 04;31(4):107587

Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA. Electronic address:

Host genetic factors play a fundamental role in regulating humoral immunity to viral infection, including influenza A virus (IAV). Here, we utilize the Collaborative Cross (CC), a mouse genetic reference population, to study genetic regulation of variation in antibody response following IAV infection. CC mice show significant heritable variation in the magnitude, kinetics, and composition of IAV-specific antibody response. We map 23 genetic loci associated with this variation. Analysis of a subset of these loci finds that they broadly affect the antibody response to IAV as well as other viruses. Candidate genes are identified based on predicted variant consequences and haplotype-specific expression patterns, and several show overlap with genes identified in human mapping studies. These findings demonstrate that the host antibody response to IAV infection is under complex genetic control and highlight the utility of the CC in modeling and identifying genetic factors with translational relevance to human health and disease.
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http://dx.doi.org/10.1016/j.celrep.2020.107587DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7195006PMC
April 2020

Immune Predictors of Mortality After Ribonucleic Acid Virus Infection.

J Infect Dis 2020 03;221(6):882-889

Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.

Background: Virus infections result in a range of clinical outcomes for the host, from asymptomatic to severe or even lethal disease. Despite global efforts to prevent and treat virus infections to limit morbidity and mortality, the continued emergence and re-emergence of new outbreaks as well as common infections such as influenza persist as a health threat. Challenges to the prevention of severe disease after virus infection include both a paucity of protective vaccines as well as the early identification of individuals with the highest risk that may require supportive treatment.

Methods: We completed a screen of mice from the Collaborative Cross (CC) that we infected with influenza, severe acute respiratory syndrome-coronavirus, and West Nile virus.

Results: The CC mice exhibited a range of disease manifestations upon infections, and we used this natural variation to identify strains with mortality after infection and strains exhibiting no mortality. We then used comprehensive preinfection immunophenotyping to identify global baseline immune correlates of protection from mortality to virus infection.

Conclusions: These data suggest that immune phenotypes might be leveraged to identify humans at highest risk of adverse clinical outcomes upon infection, who may most benefit from intensive clinical interventions, in addition to providing insight for rational vaccine design.
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http://dx.doi.org/10.1093/infdis/jiz531DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7107456PMC
March 2020

Mouse Models as Resources for Studying Infectious Diseases.

Clin Ther 2019 10 18;41(10):1912-1922. Epub 2019 Sep 18.

Department of Genetics, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Department of Microbiology and Immunology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. Electronic address:

Mouse models are important tools both for studying the pathogenesis of infectious diseases and for the preclinical evaluation of vaccines and therapies against a wide variety of human pathogens. The use of genetically defined inbred mouse strains, humanized mice, and gene knockout mice has allowed the research community to explore how pathogens cause disease, define the role of specific host genes in either controlling or promoting disease, and identify potential targets for the prevention or treatment of a wide range of infectious agents. This review discusses several of the most commonly used mouse model systems, as well as new resources such as the Collaborative Cross as models for studying infectious diseases.
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http://dx.doi.org/10.1016/j.clinthera.2019.08.010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7112552PMC
October 2019

Studies on Dibenzylamines as Inhibitors of Venezuelan Equine Encephalitis Virus.

ACS Infect Dis 2019 12 11;5(12):2014-2028. Epub 2019 Jul 11.

Chemistry Department, Drug Discovery Division , Southern Research , 2000 Ninth Avenue South , Birmingham , Alabama 35205 , United States.

Alphaviruses are arthropod-transmitted members of the Togaviridae family that can cause severe disease in humans, including debilitating arthralgia and severe neurological complications. Currently, there are no approved vaccines or antiviral therapies directed against the alphaviruses, and care is limited to treating disease symptoms. A phenotypic cell-based high-throughput screen was performed to identify small molecules that inhibit the replication of Venezuelan Equine Encephalitis Virus (VEEV). The compound, 1-(2,3-dihydrobenzo[][1,4]dioxin-6-yl)--(3-fluoro-4-methoxybenzyl)ethan-1-amine (), was identified as a highly active, potent inhibitor of VEEV with an effective concentration for 90% inhibition of virus (EC) of 0.89 μM and 7.49 log reduction in virus titers at 10 μM concentration. These data suggest that further investigation of compound as an antiviral therapeutic against VEEV, and perhaps other alphaviruses, is warranted. Experiments suggested that the antiviral activity of compound is directed at an early step in the VEEV replication cycle by blocking viral RNA and protein synthesis.
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http://dx.doi.org/10.1021/acsinfecdis.9b00035DOI Listing
December 2019

The Collaborative Cross: A Systems Genetics Resource for Studying Host-Pathogen Interactions.

Cell Host Microbe 2019 04;25(4):484-498

Department of Microbiology and Immunology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Department of Genetics, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. Electronic address:

Host genetic variation has a major impact on infectious disease susceptibility. The study of pathogen resistance genes, largely aided by mouse models, has significantly advanced our understanding of infectious disease pathogenesis. The Collaborative Cross (CC), a newly developed multi-parental mouse genetic reference population, serves as a tractable model system to study how pathogens interact with genetically diverse populations. In this review, we summarize progress utilizing the CC as a platform to develop improved models of pathogen-induced disease and to map polymorphic host response loci associated with variation in susceptibility to pathogens.
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http://dx.doi.org/10.1016/j.chom.2019.03.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6494101PMC
April 2019

Src Family Kinase Inhibitors Block Translation of Alphavirus Subgenomic mRNAs.

Antimicrob Agents Chemother 2019 04 27;63(4). Epub 2019 Mar 27.

Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, Oregon, USA

Alphaviruses are arthropod-transmitted RNA viruses that can cause arthralgia, myalgia, and encephalitis in humans. Since the role of cellular kinases in alphavirus replication is unknown, we profiled kinetic changes in host kinase abundance and phosphorylation following chikungunya virus (CHIKV) infection of fibroblasts. Based upon the results of this study, we treated CHIKV-infected cells with kinase inhibitors targeting the Src family kinase (SFK)-phosphatidylinositol 3-kinase (PI3K)-AKT-mTORC signaling pathways. Treatment of cells with SFK inhibitors blocked the replication of CHIKV as well as multiple other alphaviruses, including Mayaro virus, O'nyong-nyong virus, Ross River virus, and Venezuelan equine encephalitis virus. Dissecting the effect of SFK inhibition on alphavirus replication, we found that viral structural protein levels were significantly reduced, but synthesis of viral genomic and subgenomic RNAs was unaffected. By measuring the association of viral RNA with polyribosomes, we found that the SFK inhibitor dasatinib blocks alphavirus subgenomic RNA translation. Our results demonstrate a role for SFK signaling in alphavirus subgenomic RNA translation and replication. Targeting host factors involved in alphavirus replication represents an innovative, perhaps paradigm-shifting, strategy for exploring the replication of CHIKV and other alphaviruses while promoting antiviral therapeutic development.
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http://dx.doi.org/10.1128/AAC.02325-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6496153PMC
April 2019

Complement Activation Contributes to Severe Acute Respiratory Syndrome Coronavirus Pathogenesis.

mBio 2018 10 9;9(5). Epub 2018 Oct 9.

Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina, USA

Acute respiratory distress syndrome (ARDS) is immune-driven pathologies that are observed in severe cases of severe acute respiratory syndrome coronavirus (SARS-CoV) infection. SARS-CoV emerged in 2002 to 2003 and led to a global outbreak of SARS. As with the outcome of human infection, intranasal infection of C57BL/6J mice with mouse-adapted SARS-CoV results in high-titer virus replication within the lung, induction of inflammatory cytokines and chemokines, and immune cell infiltration within the lung. Using this model, we investigated the role of the complement system during SARS-CoV infection. We observed activation of the complement cascade in the lung as early as day 1 following SARS-CoV infection. To test whether this activation contributed to protective or pathologic outcomes, we utilized mice deficient in C3 (C3), the central component of the complement system. Relative to C57BL/6J control mice, SARS-CoV-infected mice exhibited significantly less weight loss and less respiratory dysfunction despite equivalent viral loads in the lung. Significantly fewer neutrophils and inflammatory monocytes were present in the lungs of mice than in C56BL/6J controls, and subsequent studies revealed reduced lung pathology and lower cytokine and chemokine levels in both the lungs and the sera of mice than in controls. These studies identify the complement system as an important host mediator of SARS-CoV-induced disease and suggest that complement activation regulates a systemic proinflammatory response to SARS-CoV infection. Furthermore, these data suggest that SARS-CoV-mediated disease is largely immune driven and that inhibiting complement signaling after SARS-CoV infection might function as an effective immune therapeutic. The complement system is a critical part of host defense to many bacterial, viral, and fungal infections. It works alongside pattern recognition receptors to stimulate host defense systems in advance of activation of the adaptive immune response. In this study, we directly test the role of complement in SARS-CoV pathogenesis using a mouse model and show that respiratory disease is significantly reduced in the absence of complement even though viral load is unchanged. Complement-deficient mice have reduced neutrophilia in their lungs and reduced systemic inflammation, consistent with the observation that SARS-CoV pathogenesis is an immune-driven disease. These data suggest that inhibition of complement signaling might be an effective treatment option following coronavirus infection.
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http://dx.doi.org/10.1128/mBio.01753-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6178621PMC
October 2018

Genetic control of alphavirus pathogenesis.

Mamm Genome 2018 08 27;29(7-8):408-424. Epub 2018 Aug 27.

Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.

Alphaviruses, members of the positive-sense, single-stranded RNA virus family Togaviridae, represent a re-emerging public health concern worldwide as mosquito vectors expand into new geographic ranges. Members of the alphavirus genus tend to induce clinical disease characterized by rash, arthralgia, and arthritis (chikungunya virus, Ross River virus, and Semliki Forest virus) or encephalomyelitis (eastern equine encephalitis virus, western equine encephalitis virus, and Venezuelan equine encephalitis virus), though some patients who recover from the initial acute illness may develop long-term sequelae, regardless of the specific infecting virus. Studies examining the natural disease course in humans and experimental infection in cell culture and animal models reveal that host genetics play a major role in influencing susceptibility to infection and severity of clinical disease. Genome-wide genetic screens, including loss of function screens, microarrays, RNA-sequencing, and candidate gene studies, have further elucidated the role host genetics play in the response to virus infection, with the immune response being found in particular to majorly influence the outcome. This review describes the current knowledge of the mechanisms by which host genetic factors influence alphavirus pathogenesis and discusses emerging technologies that are poised to increase our understanding of the complex interplay between viral and host genetics on disease susceptibility and clinical outcome.
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http://dx.doi.org/10.1007/s00335-018-9776-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6488303PMC
August 2018

Development of a Broadly Accessible Venezuelan Equine Encephalitis Virus Replicon Particle Vaccine Platform.

J Virol 2018 06 14;92(11). Epub 2018 May 14.

Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA

Zoonotic viruses circulate as swarms in animal reservoirs and can emerge into human populations, causing epidemics that adversely affect public health. Portable, safe, and effective vaccine platforms are needed in the context of these outbreak and emergence situations. In this work, we report the generation and characterization of an alphavirus replicon vaccine platform based on a non-select agent, attenuated Venezuelan equine encephalitis (VEE) virus vaccine, strain 3526 (VRP 3526). Using both noroviruses and coronaviruses as model systems, we demonstrate the utility of the VRP 3526 platform in the generation of recombinant proteins, production of virus-like particles, and efficacy as a vaccine against emergent viruses. Importantly, packaging under biosafety level 2 (BSL2) conditions distinguishes VRP 3526 from previously reported alphavirus platforms and makes this approach accessible to the majority of laboratories around the world. In addition, improved outcomes in the vulnerable aged models as well as against heterologous challenge suggest improved efficacy compared to that of previously attenuated VRP approaches. Taking these results together, the VRP 3526 platform represents a safe and highly portable system that can be rapidly deployed under BSL2 conditions for generation of candidate vaccines against emerging microbial pathogens. While VEE virus replicon particles provide a robust, established platform for antigen expression and vaccination, its utility has been limited by the requirement for high-containment-level facilities for production and packaging. In this work, we utilize an attenuated vaccine strain capable of use at lower biocontainment level but retaining the capacity of the wild-type replicon particle. Importantly, the new replicon platform provides equal protection for aged mice and following heterologous challenge, which distinguishes it from other attenuated replicon platforms. Together, the new system represents a highly portable, safe system for use in the context of disease emergence.
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http://dx.doi.org/10.1128/JVI.00027-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5952155PMC
June 2018

Structural divergence creates new functional features in alphavirus genomes.

Nucleic Acids Res 2018 04;46(7):3657-3670

Department of Biology, UNC-Chapel Hill, USA.

Alphaviruses are mosquito-borne pathogens that cause human diseases ranging from debilitating arthritis to lethal encephalitis. Studies with Sindbis virus (SINV), which causes fever, rash, and arthralgia in humans, and Venezuelan equine encephalitis virus (VEEV), which causes encephalitis, have identified RNA structural elements that play key roles in replication and pathogenesis. However, a complete genomic structural profile has not been established for these viruses. We used the structural probing technique SHAPE-MaP to identify structured elements within the SINV and VEEV genomes. Our SHAPE-directed structural models recapitulate known RNA structures, while also identifying novel structural elements, including a new functional element in the nsP1 region of SINV whose disruption causes a defect in infectivity. Although RNA structural elements are important for multiple aspects of alphavirus biology, we found the majority of RNA structures were not conserved between SINV and VEEV. Our data suggest that alphavirus RNA genomes are highly divergent structurally despite similar genomic architecture and sequence conservation; still, RNA structural elements are critical to the viral life cycle. These findings reframe traditional assumptions about RNA structure and evolution: rather than structures being conserved, alphaviruses frequently evolve new structures that may shape interactions with host immune systems or co-evolve with viral proteins.
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http://dx.doi.org/10.1093/nar/gky012DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6283419PMC
April 2018

Ross River virus envelope glycans contribute to disease through activation of the host complement system.

Virology 2018 02 8;515:250-260. Epub 2018 Jan 8.

Dept. of Microbiology and Immunology, University of North Carolina at Chapel Hill, 160 Dental Circle, 9024 Burnett Womack, Chapel Hill, NC 27599, USA; Dept. of Genetics, University of North Carolina at Chapel Hill, 160 Dental Circle, 9024 Burnett Womack, Chapel Hill, NC 27599, USA. Electronic address:

Mannose binding lectin (MBL) generally plays a protective role during viral infection, yet MBL-mediated complement activation promotes Ross River virus (RRV)-induced inflammatory tissue destruction, contributing to arthritis and myositis. As MBL binds to carbohydrates, we hypothesized that N-linked glycans on the RRV envelope glycoproteins act as ligands for MBL. Using a panel of RRV mutants lacking the envelope N-linked glycans, we found that MBL deposition onto infected cells was dependent on the E2 glycans. Moreover, the glycan-deficient viruses exhibited reduced disease and tissue damage in a mouse model of RRV-induced myositis compared to wild-type RRV, despite similar viral load and inflammatory infiltrates within the skeletal muscle. Instead, the reduced disease induced by glycan-deficient viruses was linked to decreased MBL deposition and complement activation within inflamed tissues. These results demonstrate that the viral N-linked glycans promote MBL deposition and complement activation onto RRV-infected cells, contributing to the development of RRV-induced myositis.
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http://dx.doi.org/10.1016/j.virol.2017.12.022DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7119116PMC
February 2018

Bayesian Diallel Analysis Reveals -Dependent and -Independent Effects on Response to Influenza A Virus in Mice.

G3 (Bethesda) 2018 02 2;8(2):427-445. Epub 2018 Feb 2.

Department of Genetics, University of North Carolina at Chapel Hill, North Carolina 27599

Influenza A virus (IAV) is a respiratory pathogen that causes substantial morbidity and mortality during both seasonal and pandemic outbreaks. Infection outcomes in unexposed populations are affected by host genetics, but the host genetic architecture is not well understood. Here, we obtain a broad view of how heritable factors affect a mouse model of response to IAV infection using an 8 × 8 diallel of the eight inbred founder strains of the Collaborative Cross (CC). Expanding on a prior statistical framework for modeling treatment response in diallels, we explore how a range of heritable effects modify acute host response to IAV through 4 d postinfection. Heritable effects in aggregate explained ∼57% of the variance in IAV-induced weight loss. Much of this was attributable to a pattern of additive effects that became more prominent through day 4 postinfection and was consistent with previous reports of antiinfluenza myxovirus resistance 1 () polymorphisms segregating between these strains; these additive effects largely recapitulated haplotype effects observed at the locus in a previous study of the incipient CC, and are also replicated here in a CC recombinant intercross population. Genetic dominance of protective haplotypes was observed to differ by subspecies of origin: relative to the null allele, acts dominantly whereas acts additively. After controlling for , heritable effects, though less distinct, accounted for ∼34% of the phenotypic variance. Implications for future mapping studies are discussed.
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http://dx.doi.org/10.1534/g3.117.300438DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5919740PMC
February 2018

Disruption of the Opal Stop Codon Attenuates Chikungunya Virus-Induced Arthritis and Pathology.

mBio 2017 11 14;8(6). Epub 2017 Nov 14.

Department of Microbiology & Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus responsible for several significant outbreaks of debilitating acute and chronic arthritis and arthralgia over the past decade. These include a recent outbreak in the Caribbean islands and the Americas that caused more than 1 million cases of viral arthralgia. Despite the major impact of CHIKV on global health, viral determinants that promote CHIKV-induced disease are incompletely understood. Most CHIKV strains contain a conserved opal stop codon at the end of the viral nsP3 gene. However, CHIKV strains that encode an arginine codon in place of the opal stop codon have been described, and deep-sequencing analysis of a CHIKV isolate from the Caribbean identified both arginine and opal variants within this strain. Therefore, we hypothesized that the introduction of the arginine mutation in place of the opal termination codon may influence CHIKV virulence. We tested this by introducing the arginine mutation into a well-characterized infectious clone of a CHIKV strain from Sri Lanka and designated this virus Opal524R. This mutation did not impair viral replication kinetics or Despite this, the Opal524R virus induced significantly less swelling, inflammation, and damage within the feet and ankles of infected mice. Further, we observed delayed induction of proinflammatory cytokines and chemokines, as well as reduced CD4 T cell and NK cell recruitment compared to those in the parental strain. Therefore, the opal termination codon plays an important role in CHIKV pathogenesis, independently of effects on viral replication. Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes significant outbreaks of viral arthralgia. Studies with CHIKV and other alphaviruses demonstrated that the opal termination codon within nsP3 is highly conserved. However, some strains of CHIKV and other alphaviruses contain mutations in the opal termination codon. These mutations alter the virulence of related alphaviruses in mammalian and mosquito hosts. Here, we report that a clinical isolate of a CHIKV strain from the recent outbreak in the Caribbean islands contains a mixture of viruses encoding either the opal termination codon or an arginine mutation. Mutating the opal stop codon to an arginine residue attenuates CHIKV-induced disease in a mouse model. Compared to infection with the opal-containing parental virus, infection with the arginine mutant causes limited swelling and inflammation, as well as dampened recruitment of immune mediators of pathology, including CD4 T cells and NK cells. We propose that the opal termination codon plays an essential role in the induction of severe CHIKV disease.
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http://dx.doi.org/10.1128/mBio.01456-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5686535PMC
November 2017

Permissivity of Dipeptidyl Peptidase 4 Orthologs to Middle East Respiratory Syndrome Coronavirus Is Governed by Glycosylation and Other Complex Determinants.

J Virol 2017 10 12;91(19). Epub 2017 Sep 12.

Department of Genetics, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina, USA

Middle East respiratory syndrome coronavirus (MERS-CoV) utilizes dipeptidyl peptidase 4 (DPP4) as an entry receptor. While bat, camel, and human DPP4 support MERS-CoV infection, several DPP4 orthologs, including mouse, ferret, hamster, and guinea pig DPP4, do not. Previous work revealed that glycosylation of mouse DPP4 plays a role in blocking MERS-CoV infection. Here, we tested whether glycosylation also acts as a determinant of permissivity for ferret, hamster, and guinea pig DPP4. We found that, while glycosylation plays an important role in these orthologs, additional sequence and structural determinants impact their ability to act as functional receptors for MERS-CoV. These results provide insight into DPP4 species-specific differences impacting MERS-CoV host range and better inform our understanding of virus-receptor interactions associated with disease emergence and host susceptibility. MERS-CoV is a recently emerged zoonotic virus that is still circulating in the human population with an ∼35% mortality rate. With no available vaccines or therapeutics, the study of MERS-CoV pathogenesis is crucial for its control and prevention. However, studies are limited because MERS-CoV cannot infect wild-type mice due to incompatibilities between the virus spike and the mouse host cell receptor, mouse DPP4 (mDPP4). Specifically, mDPP4 has a nonconserved glycosylation site that acts as a barrier to MERS-CoV infection. Thus, one mouse model strategy has been to modify the mouse genome to remove this glycosylation site. Here, we investigated whether glycosylation acts as a barrier to infection for other nonpermissive small-animal species, namely, ferret, guinea pig, and hamster. Understanding the virus-receptor interactions for these DPP4 orthologs will help in the development of additional animal models while also revealing species-specific differences impacting MERS-CoV host range.
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http://dx.doi.org/10.1128/JVI.00534-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5599747PMC
October 2017

Complete Genome Sequences of 15 Chikungunya Virus Isolates from Puerto Rico.

Genome Announc 2017 Jul 6;5(27). Epub 2017 Jul 6.

Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, North Carolina, USA

Here, we report the complete genome sequences of 15 chikungunya virus strains isolated from human plasma from infected patients in Puerto Rico. The results show that currently circulating chikungunya strains in Puerto Rico are closely related.
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http://dx.doi.org/10.1128/genomeA.00561-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5502852PMC
July 2017

A Reverse Genetics Platform That Spans the Zika Virus Family Tree.

mBio 2017 03 7;8(2). Epub 2017 Mar 7.

Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA

Zika virus (ZIKV), a mosquito-borne flavivirus discovered in 1947, has only recently caused large outbreaks and emerged as a significant human pathogen. In 2015, ZIKV was detected in Brazil, and the resulting epidemic has spread throughout the Western Hemisphere. Severe complications from ZIKV infection include neurological disorders such as Guillain-Barré syndrome in adults and a variety of fetal abnormalities, including microcephaly, blindness, placental insufficiency, and fetal demise. There is an urgent need for tools and reagents to study the pathogenesis of epidemic ZIKV and for testing vaccines and antivirals. Using a reverse genetics platform, we generated six ZIKV infectious clones and derivative viruses representing diverse temporal and geographic origins. These include three versions of MR766, the prototype 1947 strain (with and without a glycosylation site in the envelope protein), and H/PF/2013, a 2013 human isolate from French Polynesia representative of the virus introduced to Brazil. In the course of synthesizing a clone of a circulating Brazilian strain, phylogenetic studies identified two distinct ZIKV clades in Brazil. We reconstructed viable clones of strains SPH2015 and BeH819015, representing ancestral members of each clade. We assessed recombinant virus replication, binding to monoclonal antibodies, and virulence in mice. This panel of molecular clones and recombinant virus isolates will enable targeted studies of viral determinants of pathogenesis, adaptation, and evolution, as well as the rational attenuation of contemporary outbreak strains to facilitate the design of vaccines and therapeutics. Viral emergence is a poorly understood process as evidenced by the sudden emergence of Zika virus in Latin America and the Caribbean. Malleable reagents that both predate and span an expanding epidemic are key to understanding the virologic determinants that regulate pathogenesis and transmission. We have generated representative cDNA molecular clones and recombinant viruses that span the known ZIKV family tree, including early Brazilian isolates. Recombinant viruses replicated efficiently in cell culture and were pathogenic in immunodeficient mice, providing a genetic platform for rational vaccine and therapeutic design.
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http://dx.doi.org/10.1128/mBio.02014-16DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5340872PMC
March 2017

Animal Models of Chikungunya Virus Infection and Disease.

J Infect Dis 2016 Dec;214(suppl 5):S482-S487

Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton.

Chikungunya virus (CHIKV) is a reemerging alphavirus that causes acute febrile illness and severe joint pain in humans. Although acute symptoms often resolve within a few days, chronic joint and muscle pain can be long lasting. In the last decade, CHIKV has caused widespread outbreaks of unprecedented scale in the Americas, Asia, and the Indian Ocean island regions. Despite these outbreaks and the continued expansion of CHIKV into new areas, mechanisms of chikungunya pathogenesis and disease are not well understood. Experimental animal models are indispensable to the field of CHIKV research. The most commonly used experimental animal models of CHIKV infection are mice and nonhuman primates; each model has its advantages for studying different aspects of CHIKV disease. This review will provide an overview of animal models used to study CHIKV infection and disease and major advances in our understanding of chikungunya obtained from studies performed in these models.
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http://dx.doi.org/10.1093/infdis/jiw284DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5137241PMC
December 2016

A mouse model for MERS coronavirus-induced acute respiratory distress syndrome.

Nat Microbiol 2016 Nov 28;2:16226. Epub 2016 Nov 28.

Department of Epidemiology, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina 27599, USA.

Middle East respiratory syndrome coronavirus (MERS-CoV) is a novel virus that emerged in 2012, causing acute respiratory distress syndrome (ARDS), severe pneumonia-like symptoms and multi-organ failure, with a case fatality rate of ∼36%. Limited clinical studies indicate that humans infected with MERS-CoV exhibit pathology consistent with the late stages of ARDS, which is reminiscent of the disease observed in patients infected with severe acute respiratory syndrome coronavirus. Models of MERS-CoV-induced severe respiratory disease have been difficult to achieve, and small-animal models traditionally used to investigate viral pathogenesis (mouse, hamster, guinea-pig and ferret) are naturally resistant to MERS-CoV. Therefore, we used CRISPR-Cas9 gene editing to modify the mouse genome to encode two amino acids (positions 288 and 330) that match the human sequence in the dipeptidyl peptidase 4 receptor, making mice susceptible to MERS-CoV infection and replication. Serial MERS-CoV passage in these engineered mice was then used to generate a mouse-adapted virus that replicated efficiently within the lungs and evoked symptoms indicative of severe ARDS, including decreased survival, extreme weight loss, decreased pulmonary function, pulmonary haemorrhage and pathological signs indicative of end-stage lung disease. Importantly, therapeutic countermeasures comprising MERS-CoV neutralizing antibody treatment or a MERS-CoV spike protein vaccine protected the engineered mice against MERS-CoV-induced ARDS.
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http://dx.doi.org/10.1038/nmicrobiol.2016.226DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5578707PMC
November 2016

Transcriptional profiles of WNV neurovirulence in a genetically diverse Collaborative Cross population.

Genom Data 2016 Dec 14;10:137-140. Epub 2016 Oct 14.

Department of Immunology, and the Center for Innate Immunity and Immune Disease (CIIID), University of Washington, Seattle, WA, USA.

West Nile Virus (WNV) is a mosquito-transmitted virus from the Flaviviridae family that causes fever in 1 in 5 infected people. WNV can also become neuro-invasive and cross the blood-brain barrier leading to severe neurological symptoms in a subset of WNV infected individuals [1]. WNV neuro-invasion is believed to be influenced by a number of factors including host genetics. In order to explore these effects and recapitulate the complex immune genetic differences among individuals, we studied gene expression following WNV infection in the Collaborative Cross (CC) model. The CC is a mouse genetics resource composed of > 70 independently bred, octo-parental recombinant inbred mouse lines [2]. To identify the individual host gene expression signatures influencing protection or susceptibility to WNV disease and WNV neuroinvasion, we used the nanostring nsolver platform to quantify gene expression in brain tissue isolated from WNV-infected CC mice at days 4, 7 and 12 post-infection [3]. This nanostring technology provided a high throughput, non-amplification based mRNA quantitation method to detect immune genes involved in neuro-invasion. Data was deposited into the Gene Expression Omnibus (GEO) under accession GSE85999.
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http://dx.doi.org/10.1016/j.gdata.2016.10.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5107684PMC
December 2016