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The emergence of severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome (MERS)-CoV underscores the threat of cross-species transmission events leading to outbreaks in humans. Here we examine the disease potential of a SARS-like virus, SHC014-CoV, which is currently circulating in Chinese horseshoe bat populations. Using the SARS-CoV reverse genetics system, we generated and characterized a chimeric virus expressing the spike of bat coronavirus SHC014 in a mouse-adapted SARS-CoV backbone. The results indicate that group 2b viruses encoding the SHC014 spike in a wild-type backbone can efficiently use multiple orthologs of the SARS receptor human angiotensin converting enzyme II (ACE2), replicate efficiently in primary human airway cells and achieve in vitro titers equivalent to epidemic strains of SARS-CoV. Additionally, in vivo experiments demonstrate replication of the chimeric virus in mouse lung with notable pathogenesis. Evaluation of available SARS-based immune-therapeutic and prophylactic modalities revealed poor efficacy; both monoclonal antibody and vaccine approaches failed to neutralize and protect from infection with CoVs using the novel spike protein. On the basis of these findings, we synthetically re-derived an infectious full-length SHC014 recombinant virus and demonstrate robust viral replication both in vitro and in vivo. Our work suggests a potential risk of SARS-CoV re-emergence from viruses currently circulating in bat populations.
Corrigendum: Multiphoton imaging reveals a new leukocyte recruitment
paradigm in the glomerulus
Sapna Devi, Anqi Li, Clare L V Westhorpe, Camden Y Lo, Latasha D Abeynaike, Sarah L Snelgrove, Pam Hall, Joshua D Ooi,
Christopher G Sobey, A Richard Kitching & Michael J Hickey
Nat. Med. 19, 107–112 (2013); published online 16 December 2012; corrected after print 12 August 2015
In the published article, in the Online Methods section, it is stated that the dose of DHE used is 20 mg/kg, when in fact DHE was administered at
2 mg/kg. The error has been corrected in the HTML and PDF versions of the article.
Corrigendum: PAR1 signaling regulates the retention and recruitment of
EPCR-expressing bone marrow hematopoietic stem cells
Shiri Gur-Cohen, Tomer Itkin, Sagarika Chakrabarty, Claudine Graf, Orit Kollet, Aya Ludin, Karin Golan, Alexander Kalinkovich,
Guy Ledergor, Eitan Wong, Elisabeth Niemeyer, Ziv Porat, Ayelet Erez, Irit Sagi, Charles T Esmon, Wolfram Ruf & Tsvee Lapidot
Nat. Med. 21, 1307–1317 (2015); published online 12 October 2015; corrected after print 18 November 2015
In the version of this article initially published, the first author’s name was incorrect. The error has been corrected in the HTML and PDF versions
of the article.
Corrigendum: Myeloid-derived growth factor (C19orf10) mediates cardiac
repair following myocardial infarction
Mortimer Korf-Klingebiel, Marc R Reboll, Stefanie Klede, Torben Brod, Andreas Pich, Felix Polten, L Christian Napp, Johann Bauersachs,
Arnold Ganser, Eva Brinkmann, Ines Reimann, Tibor Kempf, Hans W Niessen, Jacques Mizrahi, Hans-Joachim Schönfeld,
Antonio Iglesias, Maria Bobadilla, Yong Wang & Kai C Wollert
Nat. Med. 21, 140–149 (2015); published online 12 January 2015; corrected after print 19 November 2015
In the version of this article initially published, the article number in reference 13 is incorrectly stated as ‘100ra190’ and should be ‘100ra90’. The
error has been corrected in the HTML and PDF versions of the article.
Corrigendum: A SARS-like cluster of circulating bat coronaviruses shows
potential for human emergence
Vineet D Menachery, Boyd L Yount Jr, Kari Debbink, Sudhakar Agnihothram, Lisa E Gralinski, Jessica A Plante, Rachel L Graham,
Trevor Scobey, Xing-Yi Ge, Eric F Donaldson, Scott H Randell, Antonio Lanzavecchia, Wayne A Marasco, Zhengli-Li Shi & Ralph S Baric
Nat. Med.; doi:10.1038/nm.3985; corrected 20 November 2015
In the version of this article initially published online, the authors omitted to acknowledge a funding source, USAID-EPT-PREDICT funding from
EcoHealth Alliance, to Z.-L.S. The error has been corrected for the print, PDF and HTML versions of this article.
Corrigendum: Long-term glycemic control using polymer-encapsulated
human stem cell–derived beta cells in immune-competent mice
Arturo J Vegas, Omid Veiseh, Mads Gürtler, Jeffrey R Millman, Felicia W Pagliuca, Andrew R Bader, Joshua C Doloff, Jie Li,
Michael Chen, Karsten Olejnik, Hok Hei Tam, Siddharth Jhunjhunwala, Erin Langan, Stephanie Aresta-Dasilva, Srujan Gandham,
James J McGarrigle, Matthew A Bochenek, Jennifer Hollister-Lock, Jose Oberholzer, Dale L Greiner, Gordon C Weir, Douglas A Melton,
Robert Langer & Daniel G Anderson
Nat. Med.; doi:10.1038/nm.4030; corrected online 18 February 2016
In the version of this article initially published online, the authors omitted acknowledgment recognizing the histology core of the Harvard Stem
Cell Institute and several individuals for their assistance. The error has been corrected for the print, PDF and HTML versions of this article.
npg © 2016 Nature America, Inc. All rights reserved.
... While the above evidence and analyses together appear to disapprove a natural origin of SARS-CoV-2's RBM, abundant literature shows that gain-of-function research, where the Spike protein of a coronavirus was specifically engineered, has repeatedly led to the successful generation of humaninfecting coronaviruses from coronaviruses of non-human origin [44][45][46][47] . ...
... Record also shows that research laboratories, for example, the Wuhan Institute of Virology (WIV), have successfully carried out such studies working with US researchers 45 and also working alone 47 . In addition, the WIV has engaged in decades-long coronavirus surveillance studies and therefore owns the world's largest collection of coronaviruses. ...
... Once they have chosen a template virus, they would first need to engineer, through molecular cloning, the Spike protein so that it can bind hACE2. The concept and cloning techniques involved in this manipulation have been well-documented in the literature [44][45][46]84,86 . With almost no risk of failing, the template bat virus could then be converted to a coronavirus that can bind hACE2 and infect humans [44][45][46] . ...
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The COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 has led to over 910,000 deaths worldwide and unprecedented decimation of the global economy. Despite its tremendous impact, the origin of SARS-CoV-2 has remained mysterious and controversial. The natural origin theory, although widely accepted, lacks substantial support. The alternative theory that the virus may have come from a research laboratory is, however, strictly censored on peer-reviewed scientific journals. Nonetheless, SARS-CoV-2 shows biological characteristics that are inconsistent with a naturally occurring, zoonotic virus. In this report, we describe the genomic, structural, medical, and literature evidence, which, when considered together, strongly contradicts the natural origin theory. The evidence shows that SARS-CoV-2 should be a laboratory product created by using bat coronaviruses ZC45 and/or ZXC21 as a template and/or backbone. Building upon the evidence, we further postulate a synthetic route for SARS-CoV-2, demonstrating that the laboratory-creation of this coronavirus is convenient and can be accomplished in approximately six months. Our work emphasizes the need for an independent investigation into the relevant research laboratories. It also argues for a critical look into certain recently published data, which, albeit problematic, was used to support and claim a natural origin of SARS-CoV-2. From a public health perspective, these actions are necessary as knowledge of the origin of SARS-CoV-2 and of how the virus entered the human population are of pivotal importance in the fundamental control of the COVID-19 pandemic as well as in preventing similar, future pandemics.
... Viral RNA shedding declines with resolution of symptoms, and may continue for days to weeks [8]. In the experimental model conducted 5 years ago, the researchers have interpreted the failure of response of the treatment as follows; evaluation of available SARS-based immune-therapeutic and prophylactic modalities revealed poor efficacy; both monoclonal antibody (mAb) and vaccine approaches failed to neutralize and protect from infection with CoVs using the novel spike protein [9]. It has been argued here that the mAb treatments were inconclusive. ...
... The IL-1 family member (IL-1F) of cytokines plays a critical role in the regulation of metabolic inflammation, particularly by pro-inflammatory members IL-1a and IL-1b. In contrast, the IL-1 receptor antagonist (also called Anakinra, recombinant IL-1Ra), also a member of the IL-1F, represents an endogenous mechanism to reduce IL-1-driven inflammation [7][8][9][10]. Anakinra is a human IL-1 receptor antagonist. ...
... It is involved in a wide variety of diseases, including chronic inflammatory rheumatologic diseases. IL-38 is a potential therapeutic inhibitory cytokine which inhibits proinflammation in viral infections including that caused by b-CoV, providing therapeutic strategy [7][8][9][10]. ...
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The SARS-CoV-2 is a β-CoV, which is enveloped by non-segmented positive- stranded RNA virüs. When β-CoV infects the respiratory tract, it can cause mild and/or severe acute respiratory syndrome with consequent release of cytokines/mediators, including interleukin (IL)-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8(CXCL8), IL-10, IP10, IL-12, IL-13, IL-17, IL-33, IL-25, IL-37, IL-38, GCSF, GM-CSF, HGF,IP-10, MCP-1, MIP-1α(also known as CCL3), IFN-γ, IFN-α, TRAIL, MCSF and TNF-α. Our hypothesis of writing this article can be summarized as; if the monoclonal antibody administered by us does not inhibit the immune response for the β-CoV and inhibits uncontrolled-adaptive/hyperimmune responses (also called cytokine storm) on endothelium level, then it may cause severe coronavirus disease 2019 (COVID-19). Anakinra is a human IL-1 receptor antagonist. By inhibiting IL-1α/IL-1β competitively from binding to the IL-1 type-I receptor, anakinra, neutralizes the activity that pertains to these key mediators of autoinflammatory and/or immune processes. Tocilizumab is a blocker of IL-6R that can effectively block IL-6 signal transduction pathway. Omalizumab that binds to the CH3 domain, is near to the binding site for the high-affinity IgE Fc receptors type-I of human IgE. Myocardial, lung and hepatorenal injury in patients with Covid-19 could be due to cytokine storm, hypoxic injury, or/and direct endothelial/vasculer injury. We propose combination of monoclonal antibodies with remdesivir and/or favipiravir in severe Covid-19 cases such as septic shock, acute respiratory deficiency syndrome and/or multiple organ failure. Finally, we highlight the therapeutic monoclonal antibodies that target patients with severe Covid-19.
... In view of this background, it was speculated that although this novel coronavirus might have first originated from animals and now jumped into humans, the mode of person-to-person transmission could gain prominence. Contraction of the viral infection by patients with no known history of exposure to markets or animals might be from rapid intercity spreading, even possibly by air travel [12,13] had predicted a potential threat posed by the circulating bat SARS-like CoV SHC014 because of the ability of chimeric SHC014 viruses to replicate in human airway cultures [13,14]. It was reported that SARS-like coronaviruses, isolated from Chinese horseshoe bats may gain the ability to attach to Angiotensin Converting Enzyme 2 (ACE2) receptors in the lower respiratory tract of humans. ...
... In view of this background, it was speculated that although this novel coronavirus might have first originated from animals and now jumped into humans, the mode of person-to-person transmission could gain prominence. Contraction of the viral infection by patients with no known history of exposure to markets or animals might be from rapid intercity spreading, even possibly by air travel [12,13] had predicted a potential threat posed by the circulating bat SARS-like CoV SHC014 because of the ability of chimeric SHC014 viruses to replicate in human airway cultures [13,14]. It was reported that SARS-like coronaviruses, isolated from Chinese horseshoe bats may gain the ability to attach to Angiotensin Converting Enzyme 2 (ACE2) receptors in the lower respiratory tract of humans. ...
... It was reported that SARS-like coronaviruses, isolated from Chinese horseshoe bats may gain the ability to attach to Angiotensin Converting Enzyme 2 (ACE2) receptors in the lower respiratory tract of humans. This mechanism to gain entry may facilitate cross infectivity of human hosts [13,14]. They had warned about the high probability of this mutated virus to evade current therapeutics. ...
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The global impact of the 2019 novel coronavirus (Severe Acute Respiratory Syndrome Coronavirus 2(SARS-CoV-2)) that emerged in Wuhan, China is alarming due to its rapid spread to 203 countries and territories by April 2020. To date, 14,909,279 individuals have been infected which has claimed 614471 lives. Although originating in animals, the virus has adapted a human-to-human mode of transmission presently which has challenged all existing antiviral therapies. Unfortunately, no drug or vaccine has yet been approved to treat COVID-19 because available therapeutics like monoclonal antibodies, oligonucleotide-based therapies, peptides, interferon therapies and small-molecule drugs might not effectively target the virus and take too long to develop. Hence, it is likely that it will take at least a year before treatment (e.g., a vaccine) becomes available, which is distressing. Herein, we present the first nanoscale alternatives (including one of the most successful nanomedicines developed by Moderna) for the effective control and containment of COVID-19 considering the urgency of the SARS-CoV-2 outbreak.
... In this commentary, Liu et al. have also considered a "claim in Chinese social media" (without revealing the source) that a construction of a chimeric CoV (SL-SHC014-MA15 virus) with Spike gene from bat-CoV-SL-SHC014, present in the backbone of a SARS-CoV and capable of infecting human cells is the origin of SAR-SCoV-2 [20]. The information on the chimeric SL-SHC014-MA15 virus was published in 2015 by Scientists from seven American Institutes, Wuhan Institute of Virology, and the Swiss Bellinzona Institute of Microbiology [37]. The authors indicated that SARS-CoV-2 has >6,000 nucleotides difference from this chimeric SL-SHC014-MA15 virus and, thus, they completely rejected that SARS-CoV-2 has originated from it as an engineered virus [20]. ...
... Based on serological surveillance, Wang et al., in 2018, found that Bat-CoVs can directly infect humans [69], and the infections may be subclinical [70]. However, with time, China conducted bat-CoV research in collaboration with scientists/ Institutes from USA, Switzerland, Australia, Singapore, and Pakistan, among other countries [37,[70][71][72][73][74][75]. Importantly, within one month of the first reported case of COVID-19, they published the SARS-CoV-2 genome [2]. ...
... Additionally, faster rates of evolution in the tropics have been described for other RNA viruses that could favor crossspecies transmission of RNA viruses in these regions 81 . Both SARS-CoV and SADS-CoV emerged in this region, and several bat SARSr-CoVs with high zoonotic potential have recently been reported from there, although the dynamics of their circulation in wild bat populations remain poorly understood 16,61 . Importantly, the closest known relative of SARS-CoV-2, a SARS-related virus, was found in a Rhinolophus sp. ...
... In the aftermath of the SARS-CoV and MERS-CoV outbreaks, β-CoVs have been the main focus of bat-CoV studies in China, Africa, and Europe 16,17,32,36,61 . However, we have shown that α-CoVs have a higher propensity to switch host within their natural bat reservoirs, and therefore also have a high cross-species transmission potential and risk of spillover. ...
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Bats are presumed reservoirs of diverse coronaviruses (CoVs) including progenitors of Severe Acute Respiratory Syndrome (SARS)-CoV and SARS-CoV-2, the causative agent of COVID-19. However, the evolution and diversification of these coronaviruses remains poorly understood. Here we use a Bayesian statistical framework and a large sequence data set from bat-CoVs (including 630 novel CoV sequences) in China to study their macroevolution, cross-species transmission and dispersal. We find that host-switching occurs more frequently and across more distantly related host taxa in alpha- than beta-CoVs, and is more highly constrained by phylogenetic distance for beta-CoVs. We show that inter-family and -genus switching is most common in Rhinolophidae and the genus Rhinolophus. Our analyses identify the host taxa and geographic regions that define hotspots of CoV evolutionary diversity in China that could help target bat-CoV discovery for proactive zoonotic disease surveillance. Finally, we present a phylogenetic analysis suggesting a likely origin for SARS-CoV-2 in Rhinolophus spp. bats.
... Homodimers of N-terminal S1 subunit compose the spikes on the viral surface, which guides them to the host receptors and the C-terminal S2 subunit is responsible for the cell-virus membrane fusion (Cascella et al., 2020;Du et al., 2017). S1 is further divided into an N-terminal has the feature of being optimized to bind the human receptor ACE2 (Letko & Munster, 2020;Menachery et al., 2015;Walls et al., 2020). Moreover, phylogenetically SARS-CoV-2 shares approximately 82% genomic sequence identity with SARS-CoV. ...
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SARS-CoV-2 is a deadly virus that has locked down the whole universe and still prevailing at a very rapid rate. As of 11 th 2020, the reported confirmed cases of SARS-CoV-2 count reached 4,006,257 around the world, and it reported 278,892 deaths globally. There is no specific vaccination or other cure available until now. SARS-CoV-2 is highly sensitive to abiotic factors. The viral structure is strongly affected by temperature, Relative Humidity and UV Index. In our review, we studied the impact of abiotic factors on SARS-CoV-2 by using regression and correlation statistical analysis. These analyses helped out in finding that the countries with comparatively high temperature, Relative Humidity and UV Index are at lower risk of the pandemic and vice versa. The death ratio is also lower in countries with higher values of abiotic factors. Therefore, it is suggested to design specific-COVID-19‖ chambers with adjustable figures of three discussed abiotic factors and, on the same bases, isolation centers could be adjusted accordingly. The temperature of 38°C, the relative humidity of >95% and UV radiation of 254nm assisted with the airflow is optimized for lowering the activity of SARS-CoV-2 keeping in view the bearable amounts for human bodies. However, these values could be altered according to the condition of the patients.
... i human encroachment into wildlife habitats and associated habitat loss and deterioration (White & Razgour, in press), ii bat harvesting (Mildenstein, Tanshi & Racey, 2016) and guano extraction, iii cohabitation/coexistence between synanthropic bats and humans (Russo & Ancillotto, 2015;L opez-Baucells, et al., 2017), iv interactions between bats and other species that may act as intermediate hosts, including domestic (e.g. Pulliam et al., 2012;Khayat et al., 2020) and wild animals (Menachery et al., 2015) that are brought into close proximity with bats by humans, for example, in agricultural settings, animal farming or live-animal markets, v risk of pathogen transmission to bats from humans or other species (Olival et al., in press); 3 investigation of the human dimensions of bat conservation (Kingston, 2016). Conservation psychology will play a key role in changing behaviours associated with spill-over risks and in building support for bat conservation following COVID-19 (MacFarlane & Rocha, 2020). ...
... So far it is unclear whether ribavirin treatment could improve the clinical outcome of COVID-19 disease. Remdesivir (GS-5734, Gilead Science) is a prodrug of the adenine derivative and broadly against MERS-CoV, SARS-CoV and Ebola virus [172][173][174] . A COVID-19 patient from the USA recovered after treatment with intravenous remdesivir 175 . ...
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Since human coronavirus (HCoVs) was first described in the 1960s, seven strains of respiratory human coronaviruses have emerged and caused human infections. After the emergence of severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV), a pneumonia outbreak of coronavirus disease 2019 (COVID-19) caused by a novel coronavirus (SARS-CoV-2) has represented a pandemic threat to global public health in the 21st century. Without effectively prophylactic and therapeutic strategies including vaccines and antiviral drugs, these three coronaviruses have caused severe respiratory syndrome and high case-fatality rates around the world. In this review, we detail the emergence event, origin and reservoirs of all HCoVs, compare the differences with regard to structure and receptor usage, and summarize therapeutic strategies for COVID-19 that cause severe pneumonia and global pandemic.
... Although several proteins lead to the virus development cycle and the invasion of the host, the spike protein is the most important factor in deciding the host range. The spike protein present on the virus surface plays important roles in cell receptor binding and membrane fusion [3,13,14]. Research is underway to better understand the transmissibility, severity and other characteristics associated with COVID-19. It seems that most early cases have some kind of history of interaction with the original seafood market [15]. ...
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The novel coronavirus (also known by SARS-CoV2, 2019-nCoV) is a new virus responsible for an outbreak of respiratory illness known as COVID-19, which has spread very quickly to more than 206 countries around the world. The CoVs belongs to subfamily Coronavirinae of Coronaviridae family comprising genera: α, β, γ, and δ. The study is based on recently available published research, review articles worldwide along and notification of national and International agencies about the global pandemic COVID-19. The mining of data and its statistical analysis was based on the modern reliable tools to work out the global and domestic scenario. In India, the first three cases identified were in Kerala on 30 th January, 2020. Since then the India has more than 3537 COVID-19 positive cases with 83 deaths, and 274 completely recovered cases by April 05, 2K20. Currently, the novel coronavirus disease has spread to alarming situation in various countries and Indian government also announced official lockdown for 21 days till 14 th April, 2020). Based on WHO report, a total of 1,245,207 confirmed cases of coronavirus have been identified including a total of 67,910 deaths to COVID-19 outbreak and recovered 256,503 cases by 5 th April, 2020. The potential of worldwide or cross boundary international spread of COVID-19 via commercial air travel had been assessed. In a nationwide address Hon'ble Prime Minister people to practice social distancing and self quarantine along with cleanliness and hygiene. This review be able to offer meaningful information for future and may facilitate agencies decision making on strategies to handle this global pandemic public health emergency at the community, national, and international level.
This article reviews the available literature on the SARS-Cov-2 virus and its similarities with its predecessors. The mechanisms of infection due to the structure and epidemiology of the virus are described. Based on these data, the pathogenesis of COVID- 19 infection is described. Based on this, the authors suggest probable extrapulmonary target cells and target organs for the virus depending on their expression ofthe vector protein, APF-2. The article describes a classic clinical picture of the disease, possible complications of its course, and the extrapulmonary (cardiac, immunological, renal) manifestations ofthe infection. The authors traced and described the chain of knowledge about the involvement of the kidneys in the pathological process at COVID-19. Based on numerous studies, we are looking at the site of acute renal injury, coagulopathy, systemic inflammatory response in the spectrum of manifestations of COVID-19 relative to kidneys in patients with COVID-19, including those with hemodialysis. The article builds clinical-morphological associations between lung and kidney damage at COVID-19. We present new data on the pathomorphological manifestations of COVID-19 in the lungs, including own autopsy data. Specificsigns of the effects of the virus on alveolocytes and its cytopathic effect are highlighted and described. The article focuses on kidney signs of infection. The authors give new results of their own observations obtained during an autopsy of patients with COVID-19. Detailed morphological changes in kidney structures have been described, proving that the human kidney is a specific target for SARS-Cov-2 infection, and can also serve as a viral reservoir for the pathogen, playing a role in its subsequent persistence.
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Unlabelled: The receptor binding domain (RBD) of the spike (S) glycoprotein of severe acute respiratory syndrome coronavirus (SARS-CoV) is a major target of protective immunity in vivo. Although a large number of neutralizing antibodies (nAbs) have been developed, it remains unclear if a single RBD-targeting nAb or two in combination can prevent neutralization escape and, if not, attenuate viral virulence in vivo. In this study, we used a large panel of human nAbs against an epitope that overlaps the interface between the RBD and its receptor, angiotensin-converting enzyme 2 (ACE2), to assess their cross-neutralization activities against a panel of human and zoonotic SARS-CoVs and neutralization escape mutants. We also investigated the neutralization escape profiles of these nAbs and evaluated their effects on receptor binding and virus fitness in vitro and in mice. We found that some nAbs had great potency and breadth in neutralizing multiple viral strains, including neutralization escape viruses derived from other nAbs; however, no single nAb or combination of two blocked neutralization escape. Interestingly, in mice the neutralization escape mutant viruses showed either attenuation (Urbani background) or increased virulence (GD03 background) consistent with the different binding affinities between their RBDs and the mouse ACE2. We conclude that using either single nAbs or dual nAb combinations to target a SARS-CoV RBD epitope that shows plasticity may have limitations for preventing neutralization escape during in vivo immunotherapy. However, RBD-directed nAbs may be useful for providing broad neutralization and prevention of escape variants when combined with other nAbs that target a second conserved epitope with less plasticity and more structural constraint. Importance: The emergence of severe acute respiratory syndrome coronavirus (SARS-CoV) in 2002 and Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012 has resulted in severe human respiratory disease with high death rates. Their zoonotic origins highlight the likelihood of reemergence or further evolution into novel human coronavirus pathogens. Broadly neutralizing antibodies (nAbs) that prevent infection of related viruses represent an important immunostrategy for combating coronavirus infections; however, for this strategy to succeed, it is essential to uncover nAb-mediated escape pathways and to pioneer strategies that prevent escape. Here, we used SARS-CoV as a research model and examined the escape pathways of broad nAbs that target the receptor binding domain (RBD) of the virus. We found that neither single nAbs nor two nAbs in combination blocked escape. Our results suggest that targeting conserved regions with less plasticity and more structural constraint rather than the SARS-CoV RBD-like region(s) should have broader utility for antibody-based immunotherapy.
Several new viral respiratory tract infectious diseases with epidemic potential that threaten global health security have emerged in the past 15 years. In 2003, WHO issued a worldwide alert for an unknown emerging illness, later named severe acute respiratory syndrome (SARS). The disease caused by a novel coronavirus (SARS-CoV) rapidly spread worldwide, causing more than 8000 cases and 800 deaths in more than 30 countries with a substantial economic impact. Since then, we have witnessed the emergence of several other viral respiratory pathogens including influenza viruses (avian influenza H5N1, H7N9, and H10N8; variant influenza A H3N2 virus), human adenovirus-14, and Middle East respiratory syndrome coronavirus (MERS-CoV). In response, various surveillance systems have been developed to monitor the emergence of respiratory-tract infections. These include systems based on identification of syndromes, web-based systems, systems that gather health data from health facilities (such as emergency departments and family doctors), and systems that rely on self-reporting by patients. More effective national, regional, and international surveillance systems are required to enable rapid identification of emerging respiratory epidemics, diseases with epidemic potential, their specific microbial cause, origin, mode of acquisition, and transmission dynamics.
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Without an approved vaccine or treatment, Ebola outbreak management has been limited to palliative care and barrier methods to prevent transmission. These approaches, however, have yet to end the 2014 outbreak of Ebola after its prolonged presence in West Africa. Here we show that a combination of monoclonal antibodies (ZMapp), optimized from two previous antibody cocktails, is able to rescue 100% of rhesus macaques when treatment is initiated up to 5 days post-challenge. High fever, viraemia and abnormalities in blood count and blood chemistry were evident in many animals before ZMapp intervention. Advanced disease, as indicated by elevated liver enzymes, mucosal haemorrhages and generalized petechia could be reversed, leading to full recovery. ELISA and neutralizing antibody assays indicate that ZMapp is cross-reactive with the Guinean variant of Ebola. ZMapp exceeds the efficacy of any other therapeutics described so far, and results warrant further development of this cocktail for clinical use.
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Unlabelled: Although many severe acute respiratory syndrome-like coronaviruses (SARS-like CoVs) have been identified in bats in China, Europe, and Africa, most have a genetic organization significantly distinct from human/civet SARS CoVs in the receptor-binding domain (RBD), which mediates receptor binding and determines the host spectrum, resulting in their failure to cause human infections and making them unlikely progenitors of human/civet SARS CoVs. Here, a viral metagenomic analysis of 268 bat rectal swabs collected from four counties in Yunnan Province has identified hundreds of sequences relating to alpha- and betacoronaviruses. Phylogenetic analysis based on a conserved region of the RNA-dependent RNA polymerase gene revealed that alphacoronaviruses had diversities with some obvious differences from those reported previously. Full genomic analysis of a new SARS-like CoV from Baoshan (LYRa11) showed that it was 29,805 nucleotides (nt) in length with 13 open reading frames (ORFs), sharing 91% nucleotide identity with human/civet SARS CoVs and the most recently reported SARS-like CoV Rs3367, while sharing 89% with other bat SARS-like CoVs. Notably, it showed the highest sequence identity with the S gene of SARS CoVs and Rs3367, especially in the RBD region. Antigenic analysis showed that the S1 domain of LYRa11 could be efficiently recognized by SARS-convalescent human serum, indicating that LYRa11 is a novel virus antigenically close to SARS CoV. Recombination analyses indicate that LYRa11 is likely a recombinant descended from parental lineages that had evolved into a number of bat SARS-like CoVs. Importance: Although many severe acute respiratory syndrome-like coronaviruses (SARS-like CoVs) have been discovered in bats worldwide, there are significant different genic structures, particularly in the S1 domain, which are responsible for host tropism determination, between bat SARS-like CoVs and human SARS CoVs, indicating that most reported bat SARS-like CoVs are not the progenitors of human SARS CoV. We have identified diverse alphacoronaviruses and a close relative (LYRa11) to SARS CoV in bats collected in Yunnan, China. Further analysis showed that alpha- and betacoronaviruses have different circulation and transmission dynamics in bat populations. Notably, full genomic sequencing and antigenic study demonstrated that LYRa11 is phylogenetically and antigenically closely related to SARS CoV. Recombination analyses indicate that LYRa11 is a recombinant from certain bat SARS-like CoVs circulating in Yunnan Province.
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Cross-species transmission of zoonotic coronaviruses (CoVs) can result in pandemic disease outbreaks. Middle East respiratory syndrome CoV (MERS-CoV), identified in 2012, has caused 182 cases to date, with ~43% mortality, and no small animal model has been reported. MERS-CoV and Pipistrellus bat coronavirus (BtCoV) strain HKU5 of Betacoronavirus (β-CoV) subgroup 2c share >65% identity at the amino acid level in several regions, including nonstructural protein 5 (nsp5) and the nucleocapsid (N) protein, which are significant drug and vaccine targets. BtCoV HKU5 has been described in silico but has not been shown to replicate in culture, thus hampering drug and vaccine studies against subgroup 2c β-CoVs. We report the synthetic reconstruction and testing of BtCoV HKU5 containing the severe acute respiratory syndrome (SARS)-CoV spike (S) glycoprotein ectodomain (BtCoV HKU5-SE). This virus replicates efficiently in cell culture and in young and aged mice, where the virus targets airway and alveolar epithelial cells. Unlike some subgroup 2b SARS-CoV vaccines that elicit a strong eosinophilia following challenge, we demonstrate that BtCoV HKU5 and MERS-CoV N-expressing Venezuelan equine encephalitis virus replicon particle (VRP) vaccines do not cause extensive eosinophilia following BtCoV HKU5-SE challenge. Passage of BtCoV HKU5-SE in young mice resulted in enhanced virulence, causing 20% weight loss, diffuse alveolar damage, and hyaline membrane formation in aged mice. Passaged virus was characterized by mutations in the nsp13, nsp14, open reading frame 5 (ORF5) and M genes. Finally, we identified an inhibitor active against the nsp5 proteases of subgroup 2c β-CoVs. Synthetic-genome platforms capable of reconstituting emerging zoonotic viral pathogens or their phylogenetic relatives provide new strategies for identifying broad-based therapeutics, evaluating vaccine outcomes, and studying viral pathogenesis.
Two novel coronaviruses have emerged in humans in the twenty-first century: severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV), both of which cause acute respiratory distress syndrome (ARDS) and are associated with high mortality rates. There are no clinically approved vaccines or antiviral drugs available for either of these infections; thus, the development of effective therapeutic and preventive strategies that can be readily applied to new emergent strains is a research priority. In this Review, we describe the emergence and identification of novel human coronaviruses over the past 10 years, discuss their key biological features, including tropism and receptor use, and summarize approaches for developing broadly effective vaccines.
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The 2002-3 pandemic caused by severe acute respiratory syndrome coronavirus (SARS-CoV) was one of the most significant public health events in recent history. An ongoing outbreak of Middle East respiratory syndrome coronavirus suggests that this group of viruses remains a key threat and that their distribution is wider than previously recognized. Although bats have been suggested to be the natural reservoirs of both viruses, attempts to isolate the progenitor virus of SARS-CoV from bats have been unsuccessful. Diverse SARS-like coronaviruses (SL-CoVs) have now been reported from bats in China, Europe and Africa, but none is considered a direct progenitor of SARS-CoV because of their phylogenetic disparity from this virus and the inability of their spike proteins to use the SARS-CoV cellular receptor molecule, the human angiotensin converting enzyme II (ACE2). Here we report whole-genome sequences of two novel bat coronaviruses from Chinese horseshoe bats (family: Rhinolophidae) in Yunnan, China: RsSHC014 and Rs3367. These viruses are far more closely related to SARS-CoV than any previously identified bat coronaviruses, particularly in the receptor binding domain of the spike protein. Most importantly, we report the first recorded isolation of a live SL-CoV (bat SL-CoV-WIV1) from bat faecal samples in Vero E6 cells, which has typical coronavirus morphology, 99.9% sequence identity to Rs3367 and uses ACE2 from humans, civets and Chinese horseshoe bats for cell entry. Preliminary in vitro testing indicates that WIV1 also has a broad species tropism. Our results provide the strongest evidence to date that Chinese horseshoe bats are natural reservoirs of SARS-CoV, and that intermediate hosts may not be necessary for direct human infection by some bat SL-CoVs. They also highlight the importance of pathogen-discovery programs targeting high-risk wildlife groups in emerging disease hotspots as a strategy for pandemic preparedness.
Receptor recognition is a major determinant of the host range, cross-species infections, and pathogenesis of the severe acute respiratory syndrome coronavirus (SARS-CoV). A defined receptor-binding domain (RBD) in the SARS-CoV spike protein specifically recognizes its host receptor, angiotensin-converting enzyme 2 (ACE2). This article reviews the latest knowledge about how RBDs from different SARS-CoV strains interact with ACE2 from several animal species. Detailed research on these RBD/ACE2 interactions has established important principles on host receptor adaptations, cross-species infections, and future evolution of SARS-CoV. These principles may apply to other emerging animal viruses, including the recently emerged Middle East respiratory syndrome coronavirus (MERS-CoV). This paper forms part of a series of invited articles in Antiviral Research on "From SARS to MERS: 10years of research on highly pathogenic human coronaviruses".
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Revolutionary advances in DNA sequencing technology are radically changing the approach for studying and characterizing the microbial world. The sequencing of a microbial genome, which can now be achieved in preliminary form in hours, provides a wealth of information about the functional potential of the organism, its evolutionary relationships with other organisms, and clues about niche adaptation, and without the need for microbial cultivation or isolation.1 Likewise, so-called shotgun or metagenomic sequencing, which is the high-throughput simultaneous sequencing of random fragments from complex mixes of different genomes, provides insights into the potential activities of a microbial community, possible interactions between microbial community members, and the nature of their relationships with their environment (eg, a human host).
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The severe acute respiratory syndrome coronavirus accessory protein ORF6 antagonizes interferon signaling by blocking karyopherin-mediated nuclear import processes. Viral nuclear import antagonists, expressed by several highly pathogenic RNA viruses, likely mediate pleiotropic effects on host gene expression, presumably interfering with transcription factors, cytokines, hormones, and/or signaling cascades that occur in response to infection. Using bioinformatic and systems biology approaches, we evaluated the impact of nuclear import antagonism on host expression networks using human lung epithelial cells infected with either wild type virus or a mutant that does not express ORF6 protein. Microarray analysis revealed significant changes in differential gene expression with approximately twice as many upregulated genes in the mutant virus samples by 48 hours post-infection, despite identical viral titers. Our data demonstrate that ORF6 protein expression attenuates the activity of numerous karyopherin-dependent host transcription factors (VDR, CREB1, SMAD4, p53, EpasI, and Oct3/4), which are critical for establishing antiviral responses and regulating key host responses during virus infection. Results were confirmed by proteomic and chromatin immunoprecipitation assay analyses and in parallel microarray studies using infected primary human airway epithelial cell cultures. The data strongly support the hypothesis that viral antagonists of nuclear import actively manipulate host responses in specific hierarchical patterns, contributing to viral pathogenic potential in vivo. Importantly, these studies and modeling approaches not only provide templates for evaluating virus antagonism of nuclear import processes, but revealed candidate cellular genes and pathways that may significantly influence disease outcomes following severe acute respiratory syndrome coronavirus infection in vivo.