scholarly journals Development of an In Vivo Probe to Track SARS-CoV-2 Infection in Rhesus Macaques

2021 ◽  
Vol 12 ◽  
Author(s):  
Patrick J. Madden ◽  
Muhammad S. Arif ◽  
Mark E. Becker ◽  
Michael D. McRaven ◽  
Ann M. Carias ◽  
...  
Keyword(s):  
Rhesus Macaques ◽  
The Novel ◽  
Macaque Model ◽  
Viral Spread ◽  
Infection Dynamics ◽  
Probe System ◽  
Infected Cells ◽  
Novel Coronavirus ◽  
Outstanding Question

Infection with the novel coronavirus, SARS-CoV-2, results in pneumonia and other respiratory symptoms as well as pathologies at diverse anatomical sites. An outstanding question is whether these diverse pathologies are due to replication of the virus in these anatomical compartments and how and when the virus reaches those sites. To answer these outstanding questions and study the spatiotemporal dynamics of SARS-CoV-2 infection a method for tracking viral spread in vivo is needed. We developed a novel, fluorescently labeled, antibody-based in vivo probe system using the anti-spike monoclonal antibody CR3022 and demonstrated that it could successfully identify sites of SARS-CoV-2 infection in a rhesus macaque model of COVID-19. Our results showed that the fluorescent signal from our antibody-based probe could differentiate whole lungs of macaques infected for 9 days from those infected for 2 or 3 days. Additionally, the probe signal corroborated the frequency and density of infected cells in individual tissue blocks from infected macaques. These results provide proof of concept for the use of in vivo antibody-based probes to study SARS-CoV-2 infection dynamics in rhesus macaques.

scholarly journals Longitudinal bioluminescent imaging of HIV-1 infection during antiretroviral therapy and treatment interruption in humanized mice

2019 ◽  
Author(s):  
John D. Ventura ◽  
Jagadish Beloor ◽  
Edward Allen ◽  
Tongyu Zhang ◽  
Kelsey A. Haugh ◽  
...  
Keyword(s):  
Antiretroviral Therapy ◽  
Humanized Mice ◽  
Lymphoid Tissues ◽  
Bioluminescent Imaging ◽  
Viral Spread ◽  
Non Invasive ◽  
Infection Dynamics ◽  
Infected Cells ◽  
Hiv 1

AbstractNon-invasive bioluminescent imaging (NIBLI) of HIV-1 infection dynamics allows for real-time monitoring of viral spread and the localization of infected cell populations in living animals. In this report, we describe full-length replication-competent GFP and Nanoluciferase (Nluc) expressing HIV-1 reporter viruses from two clinical transmitted / founder (T/F) stains: TRJO.c and Q23.BG505. By infecting humanized mice with these HIV-1 T/F reporter viruses, we were able to directly monitor longitudinal viral spread at whole-animal resolution via NIBLI at a sensitivity of as few as 30-50 infected cells. Bioluminescent signal strongly correlated with HIV-1 infection and responded proportionally to virus suppression in vivo in animals treated daily with a combination antiretroviral therapy (cART) regimen. Longitudinal NIBLI following cART withdrawal visualized tissue-sites that harbored virus during infection recrudescence. Notably, we observed rebounding infection in the same lymphoid tissues where infection was first observed prior to ART treatment. Our work demonstrates the utility of our system for studying in vivo viral infection dynamics and identifying infected tissue regions for subsequent analyses.Author SummaryNon-invasive bioluminescent imaging (NIBLI) in small animals allows for in vivo longitudinal imaging of infection spread and pathogenesis. We have taken advantage of the small luciferase reporter protein, Nanoluciferase (Nluc), to generate a replication-competent HIV-1 reporter virus to allow for NIBLI of viral infection in humanize mice. NIBLI via Nluc enabled us to directly visualize longitudinal spreading patterns before, during, and after interruption of daily doses of combined antiretroviral therapy (cART). We observed that rebounding infection often emerged in tissue regions originally associated with infected cells prior to cART treatment. Thus, Nluc-based NIBLI of HIV-1 infection can be used as an experimental tool to study early events involved in viral dissemination and spread from initial sites of infection to draining lymphoid tissues as well as locate infected tissues for subsequent cellular characterization of HIV-1 infected cells.

scholarly journals Novel and potent inhibitors targeting DHODH are broad-spectrum antivirals against RNA viruses including newly-emerged coronavirus SARS-CoV-2

2020 ◽  
Vol 11 (10) ◽  
pp. 723-739 ◽  
Author(s):  
Rui Xiong ◽  
Leike Zhang ◽  
Shiliang Li ◽  
Yuan Sun ◽  
Minyi Ding ◽  
...  
Keyword(s):  
Broad Spectrum ◽  
Influenza A ◽  
Ebola Virus ◽  
Rna Viruses ◽  
The Novel ◽  
Knock Out ◽  
Infected Cells ◽  
Virus Zika ◽  
Novel Coronavirus

Abstract Emerging and re-emerging RNA viruses occasionally cause epidemics and pandemics worldwide, such as the on-going outbreak of the novel coronavirus SARS-CoV-2. Herein, we identified two potent inhibitors of human DHODH, S312 and S416, with favorable drug-likeness and pharmacokinetic profiles, which all showed broad-spectrum antiviral effects against various RNA viruses, including influenza A virus, Zika virus, Ebola virus, and particularly against SARS-CoV-2. Notably, S416 is reported to be the most potent inhibitor so far with an EC50 of 17 nmol/L and an SI value of 10,505.88 in infected cells. Our results are the first to validate that DHODH is an attractive host target through high antiviral efficacy in vivo and low virus replication in DHODH knock-out cells. This work demonstrates that both S312/S416 and old drugs (Leflunomide/Teriflunomide) with dual actions of antiviral and immuno-regulation may have clinical potentials to cure SARS-CoV-2 or other RNA viruses circulating worldwide, no matter such viruses are mutated or not.

scholarly journals Characterization of the SARS-CoV-2 coronavirus X4-like accessory protein

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Olanrewaju Ayodeji Durojaye ◽  
Nkwachukwu Oziamara Okoro ◽  
Arome Solomon Odiba
Keyword(s):  
Rapid Development ◽  
Protein A ◽  
The Novel ◽  
Quality Model ◽  
A Value ◽  
Model Protein ◽  
Novel Coronavirus ◽  
Global Threat

Abstract Background The novel coronavirus SARS-CoV-2 is currently a global threat to health and economies. Therapeutics and vaccines are in rapid development; however, none of these therapeutics are considered as absolute cure, and the potential to mutate makes it necessary to find therapeutics that target a highly conserved regions of the viral structure. Results In this study, we characterized an essential but poorly understood coronavirus accessory X4 protein, a core and stable component of the SARS-CoV family. Sequence analysis shows a conserved ~ 90% identity between the SARS-CoV-2 and previously characterized X4 protein in the database. QMEAN Z score of the model protein shows a value of around 0.5, within the acceptable range 0–1. A MolProbity score of 2.96 was obtained for the model protein and indicates a good quality model. The model has Ramachandran values of φ = − 57o and ψ = − 47o for α-helices and values of φ = − 130o and ψ = + 140o for twisted sheets. Conclusions The protein data obtained from this study provides robust information for further in vitro and in vivo experiment, targeted at devising therapeutics against the virus. Phylogenetic analysis further supports previous evidence that the SARS-CoV-2 is positioned with the SL-CoVZC45, BtRs-BetaCoV/YN2018B and the RS4231 Bat SARS-like corona viruses.

scholarly journals Mobility-Guided Modeling of the COVID-19 Pandemic in Metro Manila

2020 ◽  
Author(s):  
Bernhard Egwolf ◽  
O.P. Nicanor Austriaco
Keyword(s):  
The Philippines ◽  
The Novel ◽  
National Capital Region ◽  
Viral Spread ◽  
Mobility Data ◽  
National Capital ◽  
Metro Manila ◽  
The Government ◽  
Novel Coronavirus ◽  
The City

ABSTRACTCOVID-19 is a novel respiratory disease first identified in Wuhan, China, that is caused by the novel coronavirus, SARS-CoV-2. To better understand the dynamics of the COVID-19 pandemic in the Philippines, we have used real-time mobility data to modify the DELPHI Epidemiological Model recently developed at M.I.T., and to simulate the pandemic in Metro Manila. We have chosen to focus on the National Capital Region, not only because it is the nation’s demographic heart where over a tenth of the country’s population live, but also because it has been the epidemiological epicenter of the Philippine pandemic. Our UST CoV-2 model suggests that the government-imposed enhanced community quarantine (ECQ) has successfully limited the spread of the pandemic. It is clear that the initial wave of the pandemic is flattening, though suppression of viral spread has been delayed by the local pandemics in the City of Manila and Quezon City. Our data also reveals that replacing the ECQ with a General Community Quarantine (GCQ) will increase the forecasted number of deaths in the nation’s capital unless rigorous tracing and testing can be implemented to prevent a second wave of the pandemic.

scholarly journals Effect of different modes of viral spread on the dynamics of multiply infected cells in human immunodeficiency virus infection

2010 ◽  
Vol 8 (55) ◽  
pp. 289-300 ◽  
Author(s):  
Dominik Wodarz ◽  
David N. Levy
Keyword(s):  
Evolutionary Dynamics ◽  
Virological Synapse ◽  
Virus Spread ◽  
Hiv Replication ◽  
Virus Particles ◽  
Viral Spread ◽  
Experimental Systems ◽  
Infection Dynamics ◽  
Immunodeficiency Virus ◽  
Infected Cells

Infection of individual cells with more than one HIV particle is an important feature of HIV replication, which may contribute to HIV pathogenesis via the occurrence of recombination, viral complementation and other outcomes that influence HIV replication and evolutionary dynamics. A previous mathematical model of co-infection has shown that the number of cells infected with i viruses correlates with the i th power of the singly infected cell population, and this has partly been observed in experiments. This model, however, assumed that virus spread from cell to cell occurs only via free virus particles, and that viruses and cells mix perfectly. Here, we introduce a cellular automaton model that takes into account different modes of virus spread among cells, including cell to cell transmission via the virological synapse, and spatially constrained virus spread. In these scenarios, it is found that the number of multiply infected cells correlates linearly with the number of singly infected cells, meaning that co-infection plays a greater role at lower virus loads. The model further indicates that current experimental systems that are used to study co-infection dynamics fail to reflect the true dynamics of multiply infected cells under these specific assumptions, and that new experimental techniques need to be designed to distinguish between the different assumptions.

scholarly journals Identification and functional characterization in vivo of a novel splice variant of LDLR in rhesus macaques

2011 ◽  
Vol 43 (15) ◽  
pp. 911-916 ◽  
Author(s):  
Sadik H. Kassim ◽  
Luk H. Vandenberghe ◽  
Ruben Hovhannisyan ◽  
James M. Wilson ◽  
Daniel J. Rader
Keyword(s):  
Restriction Enzyme ◽  
Liver Tissue ◽  
Human Liver ◽  
Rhesus Macaques ◽  
Functional Characterization ◽  
Reference Sequence ◽  
The Novel ◽  
Ldlr Gene ◽  
Primate Model

In the course of developing a low-density lipoprotein receptor (LDLR) gene therapy treatment for homozygous familial hypercholesterolemia (HoFH), we planned to examine the efficacy in a nonhuman primate model, the rhesus macaque heterozygous for an LDL receptor mutation fed a high-fat diet. Unexpectedly, our initial cDNA sequencing studies led to the identification of a heretofore unidentified splicing isoform of the rhesus LDLR gene. Compared with the publicly available GenBank reference sequence of rhesus LDLR, the novel isoform contains a 21 bp in frame insertion. This sequence coincides with part of exon 5 and creates a site for the restriction enzyme MscI. Using this site as a marker for the 21 bp in-frame insertion, we conducted a restriction enzyme screen to examine for the prevalence of the novel isoform in rhesus liver tissue cDNA and its homolog in human liver tissue cDNA. We found that the novel isoform is the predominant LDLR cDNA found in rhesus liver and the sole LDLR cDNA found in human liver. Finally, we compared the in vivo functionality of the novel and previously identified rhesus LDLR splicing isoforms in a mouse model of HoFH.

scholarly journals How did the COVID-19 pandemic change the practice of Paediatric Endoscopists in Europe?

2020 ◽  
Author(s):  
Ilektra Athiana ◽  
Corinne Légeret ◽  
Patrick Bontems ◽  
Luigi Dall'Oglio ◽  
Paola De Angelis ◽  
...  
Keyword(s):  
At Risk ◽  
United Kingdom ◽  
European Society ◽  
Personal Protective Equipment ◽  
Protective Equipment ◽  
The Novel ◽  
Endoscopic Procedures ◽  
Viral Spread ◽  
Novel Coronavirus ◽  
Time Point

Abstract Background: As endoscopists are at risk to get infected by the novel Coronavirus SARS-CoV-2 during endoscopic procedures, the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) published recommendations regarding protection for the paediatric endoscopist and endoscopy suite staff. The aim of this survey was to investigate whether European paediatric gastroenterology centres applied the recommendations and how this extraordinary situation was handled by the different centres.Results: Twelve Paediatric European gastroenterology centers (from Belgium, Greece, Italy, Portugal, Slovenia, Spain, Switzerland, and United Kingdom) participated. Nine centres (75%) screened their patients for a possible COVID-19 infection before the procedure, the same amount of hospitals changed their practice based on the ESPGHAN recommendations. 67% of the centres reduced the staff in the endoscopy suite, 83% of the units used FFP2/3 masks and protective goggles during the procedure and 75% wore waterproof gowns.Conclusion: The global situation caused by COVID-19 changed so rapidly, and hospitals had to react immediately to protect staff and patients and could not wait for guidelines to be published. Furthermore, uniform guidelines could not be applied by all European hospitals at a certain time point of the viral spread, as different regions of Europe were not only affected differently by COVID-19, but also had different access to personal protective equipment.

scholarly journals MicroRNAs and long non-coding RNAs as potential candidates to target specific motifs of SARS-CoV-2

2020 ◽  
Author(s):  
Lucia Natarelli ◽  
Luca Parca ◽  
Fabio Virgili ◽  
Tommaso Mazza ◽  
Christian Weber ◽  
...  
Keyword(s):  
Experimental Studies ◽  
Specific Treatment ◽  
Leader Sequence ◽  
The Novel ◽  
Health Crisis ◽  
Global Pandemic ◽  
Pulmonary Arterial ◽  
Non Coding Rnas ◽  
Novel Coronavirus

Abstract The novel Coronavirus, SARS-CoV-2 disease (COVID-19) was defined as a global pandemic and induced a severe public health crisis in 2020. Covid-19 viral infection targets the human respiratory system and, at present, no specific treatment has been identified even though certain drugs have been studied and considered apparently effective in viral progression by reducing the complications in the lung epithelium. Researchers and clinicians are still struggling to find a vaccine or a specific innovative therapeutic strategy to counter COVID-19 infection.Here we describe our study indicating that SARS-CoV-2 genome contains motif sequences in the 5´UTR leader sequence that can be selectively recognized by specific human non-coding RNAs (ncRNAs), such as micro and long non-coding RNAs (miRNAs and lncRNA). Notably, some of these ncRNAs have been already utilized as oligo-based drugs in pulmonary and virus-associated diseases. We identified three selective motifs at the 5´UTR leader sequence of SARS-CoV-2 that allow viral recognition and binding of a specific group of miRNAs, some of them characterized by “GU” seed alignments. Additionally, one seed motif within miRNAs has been found to be able to bind the 5’UTR leader sequence. Among miRNAs having thermodynamically stable binding site against leader sequence and that are able interacted with Spike transcript some are involved in pulmonary arterial hypertension and anti-viral response, i.e. miR-204, miR-3661, and miR-1343. Moreover, several miRNA candidates have been already validated in vivo and specific oligo sequence are indeed available for their inhibition or overexpression.Four lncRNAs (H19, Hotair, Fendrr, and LINC05) directly interact with spike transcript (mRNA) and viral genome.In conclusion, we suggest that specific miRNAs and lncRNAs can be potential candidates to design oligonucleotide-drugs to treat COVID-19 and that our study can provide candidate hypothesis to be eventually tested in further experimental studies.

scholarly journals Development of an antibody cocktail for treatment of Sudan virus infection

2020 ◽  
Vol 117 (7) ◽  
pp. 3768-3778 ◽  
Author(s):  
Andrew S. Herbert ◽  
Jeffery W. Froude ◽  
Ramon A. Ortiz ◽  
Ana I. Kuehne ◽  
Danielle E. Dorosky ◽  
...  
Keyword(s):  
Treatment Option ◽  
Ebola Virus ◽  
Protective Efficacy ◽  
Rhesus Macaques ◽  
Macaque Model ◽  
Mammalian Expression ◽  
Significant Difference ◽  
Antibody Cocktail

Antibody-based therapies are a promising treatment option for managing ebolavirus infections. Several Ebola virus (EBOV)-specific and, more recently, pan-ebolavirus antibody cocktails have been described. Here, we report the development and assessment of a Sudan virus (SUDV)-specific antibody cocktail. We produced a panel of SUDV glycoprotein (GP)-specific human chimeric monoclonal antibodies (mAbs) using both plant and mammalian expression systems and completed head-to-head in vitro and in vivo evaluations. Neutralizing activity, competitive binding groups, and epitope specificity of SUDV mAbs were defined before assessing protective efficacy of individual mAbs using a mouse model of SUDV infection. Of the mAbs tested, GP base-binding mAbs were more potent neutralizers and more protective than glycan cap- or mucin-like domain-binding mAbs. No significant difference was observed between plant and mammalian mAbs in any of our in vitro or in vivo evaluations. Based on in vitro and rodent testing, a combination of two SUDV-specific mAbs, one base binding (16F6) and one glycan cap binding (X10H2), was down-selected for assessment in a macaque model of SUDV infection. This cocktail, RIID F6-H2, provided protection from SUDV infection in rhesus macaques when administered at 50 mg/kg on days 4 and 6 postinfection. RIID F6-H2 is an effective postexposure SUDV therapy and provides a potential treatment option for managing human SUDV infection.

scholarly journals P2Y2 purinergic receptor modulates virus yield, calcium homeostasis, and cell motility in human cytomegalovirus-infected cells

2019 ◽  
Vol 116 (38) ◽  
pp. 18971-18982 ◽  
Author(s):  
Saisai Chen ◽  
Thomas Shenk ◽  
Maciej T. Nogalski
Keyword(s):  
Cell Motility ◽  
Human Cytomegalovirus ◽  
Cell Biology ◽  
Purinergic Receptor ◽  
Purinergic Signaling ◽  
Efficient Production ◽  
Multiple Points ◽  
Viral Spread ◽  
Infected Cells

Human cytomegalovirus (HCMV) manipulates many aspects of host cell biology to create an intracellular milieu optimally supportive of its replication and spread. Our study reveals that levels of several components of the purinergic signaling system, including the P2Y2 and P2X5 receptors, are elevated in HCMV-infected fibroblasts. Knockdown and drug treatment experiments demonstrated that P2Y2 enhances the yield of virus, whereas P2X5 reduces HCMV production. The HCMV IE1 protein induces P2Y2 expression; and P2Y2-mediated signaling is important for efficient HCMV gene expression, DNA synthesis, and the production of infectious HCMV progeny. P2Y2 cooperates with the viral UL37x1 protein to regulate cystolic Ca2+ levels. P2Y2 also regulates PI3K/Akt signaling and infected cell motility. Thus, P2Y2 functions at multiple points within the viral replication cycle to support the efficient production of HCMV progeny, and it may facilitate in vivo viral spread through its role in cell migration.

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