Results 951-970 of about 1,000
  1. Emetine is a FDA-approved drug for the treatment of amebiasis. In the recent times we had also demonstrated the antiviral efficacy of emetine against some RNA and DNA viruses. Following emergence of the COVID-19, we further evaluated the in vitro antiviral activity of emetine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The therapeutic index of emetine was determined to be 10910.4, at a cytotoxic concentration 50 (CC 50 ) of 1603.8 nM and effective concentration 50 (EC 50 ) of 0.147 nM.Besides, we also demonstrated the protective efficacy of emetine against lethal challenge with infectious bronchitis virus (IBV; a chicken coronavirus) in the embryonated chicken egg infection model. Emetine treatment was shown to decrease viral RNA and protein synthesis without affecting other steps of viral life cycle such as attachment, entry and budding.In a chromatin immunoprecipitation (CHIP) assay, emetine was shown to disrupt the binding of SARS-CoV-2 RNA with eIF4E (eukaryotic translation initiation factor 4E, a cellular cap-binding protein required for initiation ofprotein translation). Further, SARS-CoV-2 was shown to exploit ERK/MNK1/eIF4E signalling pathwayfor its effective replication in the target cells. To conclude, emetine targets SARS-CoV-2 protein synthesis which is mediated via inhibiting the interaction of SARS-CoV-2 RNA with eIF4E. This is a novel mechanistic insight on the antiviral efficacy of emetine. In vitro antiviral efficacy against SARS-CoV-2 and its ability to protect chicken embryos against IBV suggests that emetine could be repurposed to treat COVID-19.
    Date: 2020-11-30
    Authors: Kumar R, Khandelwal N, Chander Y, Riyesh T, Gulati BR, Pal Y, Tripathi BN, Barua S, Kumar N.
    Ref: bioRxiv
  2. The global pandemic outbreak, SARS-COV-2, which causes COVID-19, has coerced numerous pharmaceutical companies to sprint for the vaccine and therapeutic biologics development. Most of the therapeutic biologics are common human IgG antibodies, which were identified by next-generation sequencing with the B cells from the convalescent patients in less than one-month post-infection. While the global public health emergency calls for medications urgently, it saves lives to expedite the clinical trials of biologics as much as possible, hence the biologics development strategies are unprecedentedly challenged. Since the advent of therapeutic biologics, transfection, and selection strategy has been continuously improving for developing more robust cell lines with greater productivity and efficiency. Next-generation sequencing (NGS) has also been implemented into cell bank testing for acceleration. These recent advances enable us to rethink and reshape the chemistry, manufacturing and controls (CMC) strategy against the pandemic outbreaks, to start supplying cGMP materials for the life-saving clinical trials as soon as possible. We elucidated an accelerated CMC workflow for biologics against pandemics, including using cGMP-compliant pool materials for Phase I clinical trials, selecting the final clone with similar product quality as Phase I materials for late-stage development and commercial production and matching product quality among different manufacturing stages.
    Date: 2020-11-27
    Authors: Zhang Z, Chen J, Wang J, Gao Q, Xu S, Zhang L, Cai J, Zhou W.
    Ref: Authorea Preprints
  3. Accurate diagnostics underpin effective public health responses to emerging viruses. For viruses, such as Zika virus (ZIKV), where the viremia clears quickly, antibody-based (IgM or IgG) diagnostics are recommended for patients who present seven days after symptom onset. However, cross-reactive antibody responses can complicate test interpretation among populations where closely related viruses circulate. We examined the accuracy (proportion of samples correctly categorized as Zika-positive or negative) for antibody-based diagnostics among Brazilian residents (Rio de Janeiro) during the ZIKV outbreak. Four ZIKV ELISAs (IgM and IgG Euroimmun, IgM Novagnost and CDC MAC), two dengue ELISAs (IgM and IgG Panbio), and the ZIKV plaque reduction neutralization test (PRNT) were evaluated. Positive samples were ZIKV PCR confirmed clinical cases collected in 2015-2016 (n=169); Negative samples (n=236) were collected before ZIKV was present in Brazil (≤2013). Among serum samples collected ≥7 days from symptom onset, PRNT exhibited the highest accuracy (93.7%), followed by the Euroimmun IgG ELISA (77.9%). All IgM assays exhibited lower accuracy (<74%). IgG was detected more consistently than IgM among ZIKV cases using Euroimmun ELISAs (68% versus 22%). Anti-DENV IgM ELISA was positive in 41.1% of confirmed ZIKV samples tested. The Euroimmun IgG assay, although misdiagnosing 22% of samples, provided the most accurate ELISA. Anti-ZIKV IgG was detected more reliably than IgM among ZIKV patients, suggesting a secondary antibody response to assay antigens following ZIKV infection. Antibody ELISAs need careful evaluation in their target population to optimise use and minimise misdiagnosis, prior to widespread deployment, particularly where related viruses co-circulate.
    Date: 2020-11-27
    Authors: Medialdea-Carrera R, Levy F, Castanha P, de Sequeira PC, Brasil P, Lewis-Ximenez LL, Turtle L, Solomon T, de Filippis AMB, Brown DW, Griffiths MJ.
    Ref: bioRxiv
  4. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a betacoronavirus in the subgenus Sarbecovirus causes a respiratory disease with varying symptoms referred to as coronavirus disease 2019 (COVID-19) and is responsible for a pandemic that started in early 2020. With no vaccines or effective antiviral treatments available, and infection and fatality numbers continuing to increase globally, the quest for novel therapeutic solutions remains an urgent priority. Rocaglates, a class of plant-derived cyclopenta[ b ]benzofurans, exhibit broad-spectrum antiviral activity against positive- and negative-sense RNA viruses. This compound class inhibits eukaryotic initiation factor 4A (eIF4A)-dependent mRNA translation initiation, resulting in strongly reduced viral RNA translation. The synthetic rocaglate CR-31-B (-) has previously been shown to inhibit the replication of human coronaviruses, such as HCoV-229E and MERS-CoV, as well as Zika-, Lassa-, Crimean Congo hemorrhagic fever virus in primary cells. Here, we assessed the antiviral activity of CR-31-B (-) against SARS-CoV-2 using both in vitro and ex vivo cell culture models. In African green monkey Vero E6 cells, CR-31-B (-) inhibited SARS-CoV-2 replication with an EC 50 of ~1.8 nM. In line with this, viral protein accumulation and replication/transcription complex formation were found to be strongly reduced by this compound. In an ex vivo infection system using human airway epithelial cells, CR-31-B (-) was found to cause a massive reduction of SARS-CoV-2 titers by about 4 logs to nearly non-detectable levels. The data reveal a potent anti-SARS-CoV-2 activity by CR-31-B (-), corroborating previous results obtained for other coronaviruses and supporting the idea that rocaglates may be used in first-line antiviral intervention strategies against novel and emerging RNA virus outbreaks.
    Date: 2020-11-24
    Authors: Müller C, Obermann W, Karl N, Wendel H, Taroncher-Oldenburg G, Pleschka S, Hartmann RK, Grünweller A, Ziebuhr J.
    Ref: bioRxiv
  5. Background: The impact of the COVID-19 pandemic on the incidence of notifiable infectious diseases (NID) in Taiwan remains unclear. Methods: The number of cases of NID between January and September 2019 and 2020 were obtained from the open database established by the Taiwan Centers for Disease Control for comparison. Percentage change was defined as the difference in the number of cases between 2020 and 2019, divided by the number in 2019 and multiplied by 100. Findings: Overall, 42 NID were included in this study. The number of cases was 21,895 between January and September 2020, which was lower than the number of cases during the same period in 2019 (n = 24,469), with a decline in incidence from 102.9 to 91.7 per 100,000 people in 2019 and 2020, respectively. Among these diseases, 30 infectious diseases showed a lower incidence in 2020 than in 2019. In contrast, an increase in the number of cases of 10 diseases was observed in 2020 in comparison with 2019, and 2 diseases had the same number of cases in both 2019 and 2020. Fourteen airborne/droplet, 11 fecal-oral, seven vector-borne, and four direct-contact transmitted NID had an overall reduction of 2,700 (-28.1%), 156 (-23.0%), 557 (-54.8%), and 73 (-45.9%) cases, respectively, from 2019 to 2020. Similar trends were observed for the changes in incidence, which were 11.5 (-28.4%), 6.7 (-23.4%), 2.4 (-55.0%), and 0.3 (-46.2%) per 100,000 people for airborne/droplet, fecal-oral, vector-borne, and direct-contact transmitted NID, respectively. In addition, all the 38 imported NID showed a reduction of 632 (-73.5%) cases from 2019 to 2020. In contrast, 4 sexually transmitted diseases (STDs) showed an increase of 903 (+7.2%) cases from 2019 to 2020, which was attributed to the increase in gonorrhea (from 3,220 to 5,028). The overall incidence of STDs increased from 52.5 to 56.0 per 100,000 people, with a percentage change of +6.7%. Interpretation: This study demonstrated a collateral benefit of COVID-19 prevention measures for various infectious diseases, except STDs, in Taiwan, during the COVID-19 epidemic. Funding Statement: This study did not receive any specific funding from agencies in the public, commercial, or not-for-profit sectors. Declaration of Interests: The authors have no competing interests.
    Date: 2020-11-23
    Authors: Laia C, Chen S, Yen M, Lee P, Ko W, Hsueh P.
    Ref: SSRN
  6. ABSTRACT Objective We analyzed the scientific output after COVID-19 and contrasted it with studies published in the aftermath of seven epidemics/pandemics: Severe Acute Respiratory Syndrome (SARS), Influenza A virus H5N1 and Influenza A virus H1N1 human infections, Middle East Respiratory Syndrome (MERS), Ebola virus disease, Zika virus disease, and Dengue. Design/Methodology/Approach We examined bibliometric measures for COVID-19 and the rest of studied epidemics/pandemics. Data were extracted from Web of Science, using its journal classification scheme as a proxy to quantify the multidisciplinary coverage of scientific output. We proposed a novel Thematic Dispersion Index (TDI) for the analysis of pandemic early stages. Results/Discussion The literature on the seven epidemics/pandemics before COVID-19 has shown explosive growth of the scientific production and continuous impact during the first three years following each emergence or re-emergence of the specific infectious disease. A subsequent decline was observed with the progressive control of each health emergency. We observed an unprecedented growth in COVID-19 scientific production. TDI measured for COVID-19 (29,4) in just six months, was higher than TDI of the rest (7,5 to 21) during the first three years after epidemic initiation. Conclusions COVID-19 literature showed the broadest subject coverage, which is clearly a consecuence of its social, economic, and political impact. The proposed indicator (TDI), allowed the study of multidisciplinarity, differentiating the thematic complexity of COVID-19 from the previous seven epidemics/pandemics. Originality/Value The multidisciplinary nature and thematic complexity of COVID-19 research were successfully analyzed through a scientometric perspective.
    Date: 2020-11-23
    Authors: Arencibia-Jorge R, García-García L, Galbán-Rodríguez E, Carrillo-Calvet H.
    Ref: bioRxiv
  7. Summary Background Outbreaks of infectious diseases generate outbreaks of scientific evidence. In 2016 epidemics of Zika virus emerged, largely in Latin America and the Caribbean. In 2020, a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a pandemic of coronavirus disease 2019 (COVID-19). We compared patterns of scientific publications for the two infections over time. Methods We used living systematic review methods to search for and annotate publications according to study design. For Zika virus, a review team performed the tasks for publications in 2016. For SARS-CoV-2, a crowd of 25 volunteer scientists performed the tasks for publications up to May 24, 2020. We used descriptive statistics to categorise and compare study designs over time. Findings We found 2,286 publications about Zika virus in 2016 and 21,990 about SARS-CoV-2 up to 24 May 2020, of which we analysed a random sample of 5294. For both infections, there were more epidemiological than laboratory science studies. Amongst epidemiological studies for both infections, case reports, case series and cross-sectional studies emerged first, cohort and case-control studies were published later. Trials were the last to emerge. Mathematical modelling studies were more common in SARS-CoV-2 research. The number of preprints was much higher for SARS-CoV-2 than for Zika virus. Interpretation Similarities in the overall pattern of publications might be generalizable, whereas differences are compatible with differences in the characteristics of a disease. Understanding how evidence accumulates during disease outbreaks helps us understand which types of public health questions we can answer and when. Funding MJC and HI are funded by the Swiss National Science Foundation (SNF grant number 176233). NL acknowledges funding from the European Union’s Horizon 2020 research and innovation programme - project EpiPose (grant agreement number 101003688). DBG is funded by the Swiss government excellence scholarship (2019.0774) and the Swiss School of Public Health Global P3HS.
    Date: 2020-11-23
    Authors: Ipekci AM, Buitrago-Garcia D, Meili KW, Krauer F, Prajapati N, Thapa S, Wildisen L, Chaveron LA, Baumann L, Shah S, Whiteley T, Solís-García G, Tsotra F, Zhelyazkov I, Imeri H, Low N, Counotte MJ.
    Ref: medRxiv
  8. Widespread, frequent testing is essential for curbing the ongoing COVID-19 pandemic. Because its simplicity makes it ideal for widely distributed, high throughput testing, RT-LAMP provides an attractive alternative to RT-qPCR. However, most RT-LAMP protocols require the purification of RNA, a complex and low-throughput bottleneck that has often been subject to reagent supply shortages. Here, we report an optimized RT-LAMP-based SARS-CoV-2 diagnostic protocol for saliva and swab samples. In the protocol we replace RNA purification with a simple sample preparation step using a widely available chelating agent, as well as optimize key protocol parameters. When tested on clinical swab and saliva samples, this assay achieves a limit of detection of 10 5 viral genomes per ml, with sensitivity close to 90% and specificity close to 100%, and takes 45 minutes from sample collection to result, making it well suited for a COVID-19 surveillance program.
    Date: 2020-11-22
    Authors: Flynn MJ, Snitser O, Flynn J, Green S, Yelin I, Szwarcwort-Cohen M, Kishony R, Elowitz MB.
    Ref: medRxiv
  9. This paper presents a study on 80 countries that evaluates the socioeconomic factors in containing the spread and mortality of COVID-19 pandemic with the countries whose infection and death cases are more than 30 days after the 10th case being reported. Our results show that the long-term social factors such as lower personal freedom, better education in science, and past coronavirus outbreak experience are more effective than the economic factors such as higher healthcare-associated factors per 1000 population and larger GDP. However, using GDP per capita as the instrumental variable, we also find that the richer countries with a high degree of personal freedom have a higher number of infection or death cases per million population because they would be less likely to adhere to and implement the policy of the movement restrictions to restrict their access to goods and services since they have more income to spend to maintain their higher expected utility from consumption.
    Date: 2020-11-20
    Authors: Ang J, Dong F, Patalinghug J.
    Ref: SSRN
  10. Background: SARS-CoV-2 coronavirus, an emerging Betacoronavirus, is the causative agent of the severe acute respiratory distress syndrome outbreak in 2019 (COVID-19). Currently, there are neither specific and selective antiviral drugs for the treatment nor vaccines to prevent contagion. Here we propose a bioinformatic approach in order to test in silico the efficacy of existing drugs for COVID-19. ResultsIn the first step of our study we identified, through a gene expression analysis, several drugs that could act on the biological pathways altered in COVID-19. In the second step, we performed a docking simulation in order to test the properties of the identified drugs to target the 3CL main protease of SARS-CoV-2. The drugs that showed higher binding affinity are bardoxolone (-8.78 kcal/ mol), Irinotecan (-8.40 kcal/mol) and Pyrotinib (-8.40 kcal/mol). Molecular dynamics simulations were carried out on the three selected drugs to validate the stability and interactions of the complexes. Among other promising drugs we found also AZD-8055, Olaparib, Tyrphostin AG 879, Topotecan Hydrochloride, MP-412, S-222611, Allitinib, 7-Ethyl-10-Hydroxy-Camptothecin, and Falnidamol. ConclusionsWe suggested some drugs that could efficient in COVID-19. However further studies are suggested to confirm the affinity of these drugs with 3CL main protease of SARS-CoV-2.
    Date: 2020-11-19
    Authors: Cava C, Bertoli G, Castiglioni I.
    Ref: Research Square
  11. ABSTRACT The SARS-coronavirus 2 (SARS-CoV-2) spike (S) protein mediates viral entry into cells expressing the angiotensin-converting enzyme 2 (ACE2). The S protein engages ACE2 through its receptor-binding domain (RBD), an independently folded 197-amino acid fragment of the 1273-amino acid S-protein protomer. The RBD is the primary SARS-CoV-2 neutralizing epitope and a critical target of any SARS-CoV-2 vaccine. Here we show that this RBD conjugated to each of two carrier proteins elicited more potent neutralizing responses in immunized rodents than did a similarly conjugated proline-stabilized S-protein ectodomain. Nonetheless, the native RBD expresses inefficiently, limiting its usefulness as a vaccine antigen. However, we show that an RBD engineered with four novel glycosylation sites (gRBD) expresses markedly more efficiently, and generates a more potent neutralizing responses as a DNA vaccine antigen, than the wild-type RBD or the full-length S protein, especially when fused to multivalent carriers such as an H. pylori ferritin 24-mer. Further, gRBD is more immunogenic than the wild-type RBD when administered as a subunit protein vaccine. Our data suggest that multivalent gRBD antigens can reduce costs and doses, and improve the immunogenicity, of all major classes of SARS-CoV-2 vaccines.
    Date: 2020-11-18
    Authors: Quinlan BD, He W, Mou H, Zhang L, Guo Y, Chang J, Peng S, Ojha A, Tavora R, Parcells MS, Luo G, Li W, Zhong G, Choe H, Farzan M.
    Ref: bioRxiv
  12. The COVID-19 pandemic has underscored the shortcomings in the deployment of state-of-the-art diagnostic platforms. Although several PCR-based techniques have been rapidly developed to meet the growing testing needs, such techniques often need samples collected through a swab, the use of RNA extraction kits, and expensive thermocyclers in order to successfully perform the test. Isothermal amplification-based approaches have also been recently demonstrated for rapid SARS-CoV-2 detection by minimizing sample preparation while also reducing the instrumentation and reaction complexity. There are limited reports of saliva as the sample source and some of these indicate inferior sensitivity when comparing RT-LAMP with PCR-based techniques. In this paper, we demonstrate an improved sensitivity assay to test saliva using a 2-step RT-LAMP assay, where a short 10-minute RT step is performed with only B3 and BIP primers before the final reaction. We show that while the 1-step RT-LAMP demonstrate satisfactory results, the optimized 2-step approach allows for single molecule sensitivity per reaction and performs significantly better than the 1-step RT-LAMP and conventional 2-step RT-LAMP approaches with all primers included in the RT Step. Importantly, we demonstrate RNA extraction-free RT-LAMP based assays for detection of SARS-CoV-2 from VTM and saliva clinical samples.
    Date: 2020-11-18
    Authors: Ganguli A, Mostafa A, Berger J, Stewart de Ramirez SA, Baltaji A, Roth K, Aamir M, Aedma S, Mady M, Mahajan P, Sathe S, Johnson M, White K, Kumar J, Valera E, Bashir R.
    Ref: medRxiv
  13. The SARS-Cov-2 pandemic has forced all countries worldwide to rapidly develop and implement widespread testing to control and manage the Coronavirus Disease 2019 (COVID-19). RT-qPCR is the gold standard molecular diagnostic method for COVID-19, mostly in automated testing platforms. These systems are accurate and effective, but also costly, time-consuming, high technological, infrastructure dependent and currently suffer from commercial reagent supply shortages. The reverse-transcription loop-mediated isothermal amplification (RT-LAMP) can be used as alternative testing method. Here, we present a novel versatile (real-time and colorimetric) RT-LAMP for the simple (one-step) and rapid (as soon as 9 min) detection of SARS-CoV-2 and demonstrate the assay on RT-qPCR-positive clinical samples. We further transformed the RT-LAMP into a dry format for room-temperature storage suitable for potentially ready-to-use COVID-19 diagnosis. After further testing and validation, the Dry-RT-LAMP could be easily applied both in developed and in low-income countries yielding rapid and reliable results.
    Date: 2020-11-16
    Authors: Diego JG, Fernández-Soto P, Domínghez-Gil M, Belhassen-García M, Bellido JLM, Muro A.
    Ref: Research Square
  14. Capsid-anchor (CA) of Zika virus (ZIKV) is a small, single-pass transmembrane sequence that separates the capsid (C) protein from downstream pre-membrane (PrM) protein. During ZIKV polyprotein processing, CA is cleaved-off from C and PrM and left as a membrane-embedded peptide. CA plays an essential role in the assembly and maturation of the virus. However, its independent folding behavior is still unknown. Since misfolding and aggregation propensity of transmembrane proteins are now increasingly recognized and has been linked to several proteopathic disorders. Therefore, in this study, we investigated the amyloid-forming propensity of CA at physiological conditions. We observed aggregation behavior of CA peptide using dyebinding assays and ThT kinetics. The morphological analysis of CA aggregates explored by high-resolution microscopy (TEM and AFM) revealed characteristic amyloid-like fibrils. Further, the effect on mammalian cells exhibited the cytotoxic nature of the CA amyloid-fibrils. Our findings collectively shed light on the amyloidogenic phenomenon of flaviviral protein, which may contribute to their infection. Graphical Abstract: Schematic representation of Zika virus Capsid anchor forming amyloid aggregates with cytotoxic and hemolytic properties.
    Date: 2020-11-14
    Authors: Saumya KU, Gadhave K, Kumar A, Giri R.
    Ref: bioRxiv
  15. SARS-CoV-2 is the causative agent for the COVID-19 pandemic and there is an urgent need to understand the cellular response to SARS-CoV-2 infection. Beclin-1 is an essential scaffold autophagy protein that forms two distinct subcomplexes with modulators Atg14 and UVRAG, responsible for autophagosome formation and maturation, respectively. In the present study, we found that SARS-CoV-2 infection triggers an incomplete autophagy response, elevated autophagosome formation but impaired autophagosome maturation, and declined autophagy by genetic knockout of essential autophagic genes reduces SARS-CoV-2 replication efficiency. By screening 28 viral proteins of SARS-CoV-2, we demonstrated that expression of ORF3a alone is sufficient to induce incomplete autophagy. Mechanistically, SARS-CoV-2 ORF3a interacts with autophagy regulator UVRAG to facilitate Beclin-1-Vps34-Atg14 complex but selectively inhibit Beclin-1-Vps34-UVRAG complex. Interestingly, although SARS-CoV ORF3a shares 72.7% amino acid identity with the SARS-CoV-2 ORF3a, the former had no effect on cellular autophagy response. Thus, our findings provide the mechanistic evidence of possible takeover of host autophagy machinery by ORF3a to facilitate SARS-CoV-2 replication and raises the possibility of targeting the autophagic pathway for the treatment of COVID-19.
    Date: 2020-11-14
    Authors: Qu Y, Wang X, Zhu Y, Wang Y, Yang X, Hu G, Liu C, Li J, Ren S, Xiao Z, Liu Z, Wang W, Li P, Zhang R, Liang Q.
    Ref: Research Square
  16. Aims: : To explore the clinical characteristics and placental pathological changes of pregnant women with 2019 novel coronavirus (CoV) disease (COVID-19) in the third trimester, and to assess the possibility of vertical transmission. Methods: and results: The placenta tissues were evaluated by using immunohistochemistry for inflammatory cells and Hofbauer cells, and using severe acute respiratory syndrome (SARS) CoV-2 RNA Fluorescence In-Situ Hybridization (FISH) and SARS-CoV-2 spike protein immunofluorescence (IF) double staining. All Eight placentas from the third trimester pregnancy women were studied. all patients were cured, no clinical or serological evidence pointed to vertical transmission of SARS-CoV-2. Features of maternal vascular malperfusion (MVM) such as increased syncytial knots were present in all 8 cases (8/8), and increased focal perivillous fibrin depositions were presented in 7 cases (7/8). No significate inflammatory cell reaction was noted in the placenta. The number of macrophages and inflammatory cells such as T cells, B cells and plasma cells in the placental villous was not significantly increased in all cases. Moreover, all of eight cases demonstrated negative results by FISH using a SARS-CoV-2 virus RNA probe and by IF using a monoclonal antibody against SARS-CoV-2 spike protein. Conclusions: : We found no evidence of vertical transmission and adverse maternal-fetal outcomes in the placentas of third trimester COVID-19 pregnancy women, which provided further information for the clinical management of those women in the third trimester. However, further studies are still needed for patients with infections in different stage of gestation, especially in first and second trimester.
    Date: 2020-11-13
    Authors: Gao L, Ren J, Xu L, Ke X, Xiong L, Tian X, Fan C, Yan H, Yuan J.
    Ref: Research Square
  17. The SARS-CoV2 is a highly contagious pathogen that causes COVID-19 disease. It has affected millions of people globally with an average lethality of ~3%. Unfortunately, there is no standard cure for the disease, although some drugs are under clinical trial. Thus, there is an urgent need of drugs for the treatment of COVID-19. In the current studies, we have used state of the art bioinformatics techniques to screen the FDA approved drugs against nine SARS-CoV2 proteins to identify drugs for quick repurposing. The strategy was to identify potential drugs that can target multiple viral proteins simultaneously. Additionally, we analyzed if the identified molecules can also affect the human proteins whose expression is differentially modulated during SARS-CoV2 infection. The differentially expressed genes (DEGs) as a result of SARS-CoV2 infection were identified using NCBI-GEO data (GEO-ID: GSE-147507). Targeting such genes may also be a beneficial strategy to curb disease manifestation. We have identified 74 molecules that can bind to various SARS-CoV2 and human host proteins. Their possible use in COVID-19 have also been reviewed in detail. We hope that this study will help development of multipotent drugs, simultaneously targeting the viral and host proteins, for the treatment of COVID-19.
    Date: 2020-11-13
    Authors: Kumar S, Kumari P, Agnihotri G, Kumar PV, Singh B, Khan S, Beuria TK, Syed GH, Dixit A.
    Ref: Research Square
  18. The ZIKA virus has caused a heavy concern everywhere the globe because of its high infectivity and mortality rate. Still, there’s no specific drug or preventive medication to treat ZIKA infection despite comprehensive analysis by the researchers. This study was designed to demonstrate the efficacy of some plant derived bioactive compounds against ZIKV by using both structure and ligand based virtual screening methods. A number of 35 plant metabolites were screened against ZIKA NS2B-NS3 protease (5LC0), Envelop protein (5JHM), Capsid protein (5YGH) and NS5 RNA-dependent RNA polymerase protein (5U04) employing molecular docking approach. Results showed that there have been four metabolites, i.e. Chicoric acid, Luteone, Reserpine and Rosmarinic acid provide highest binding affinity to targeted ZIKV proteins. Crucial binding sites and drug surface hotspots are unraveled for every targeted viral protein. The ADME study showed that neither of the candidate compounds had side effects that would reduce their drug-like properties. As compared, the toxicity pattern analysis has unmasked the non-toxic essence of top drug candidates. The RMSD values of ligand-macromolecule complexes were 2 Å apart from Envelop protein- Chicoric Acid, although the RMSF values showed normal atomic fluctuations within the molecular dynamics analysis, with the exception of Envelop protein- Chicoric Acid. The expected majority of the target class the highest drug candidates is enzyme classes (e.g. protease, hydrolase, phosphatase). In addition, the drug similarity prediction revealed several structural analogs from drugbank such as Isoformononetin (DB04202), Deserpidine (DB01089) and Rescinnamine (DB01180) etc. and these analogs could even be an option for the treatment of ZIKV infections. The study can pave the way for the creation of effective ZIKV medications and preventive measures. We highly recommend further in vivo trials for the experimental validation of our findings.
    Date: 2020-11-12
    Authors: Ahmed SR, Banik A, Anni SM, Chowdhury MMH.
    Ref: bioRxiv
  19. ABSTRACT Currently, more than 33 million peoples have been infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and more than a million people died from coronavirus disease 2019 (COVID-19), a disease caused by the virus. There have been multiple reports of autoimmune and inflammatory diseases following SARS-CoV-2 infections. There are several suggested mechanisms involved in the development of autoimmune diseases, including cross-reactivity (molecular mimicry). A typical workflow for discovering cross-reactive epitopes (mimotopes) starts with a sequence similarity search between protein sequences of human and a pathogen. However, sequence similarity information alone is not enough to predict cross-reactivity between proteins since proteins can share highly similar conformational epitopes whose amino acid residues are situated far apart in the linear protein sequences. Therefore, we used a hidden Markov model-based tool to identify distant viral homologs of human proteins. Also, we utilized experimentally determined and modeled protein structures of SARS-CoV-2 and human proteins to find homologous protein structures between them. Next, we predicted binding affinity (IC50) of potentially cross-reactive T-cell epitopes to 34 MHC allelic variants that have been associated with autoimmune diseases using multiple prediction algorithms. Overall, from 8,138 SARS-CoV-2 genomes, we identified 3,238 potentially cross-reactive B-cell epitopes covering six human proteins and 1,224 potentially cross-reactive T-cell epitopes covering 285 human proteins. To visualize the predicted cross-reactive T-cell and B-cell epitopes, we developed a web-based application “Molecular Mimicry Map (3M) of SARS-CoV-2” (available at https://ahs2202.github.io/3M/ ). The web application enables researchers to explore potential cross-reactive SARS-CoV-2 epitopes alongside custom peptide vaccines, allowing researchers to identify potentially suboptimal peptide vaccine candidates or less ideal part of a whole virus vaccine to design a safer vaccine for people with genetic and environmental predispositions to autoimmune diseases. Together, the computational resources and the interactive web application provide a foundation for the investigation of molecular mimicry in the pathogenesis of autoimmune disease following COVID-19.
    Date: 2020-11-12
    Authors: An H, Park J.
    Ref: bioRxiv
  20. Zika virus (ZIKV) infection of pregnant women can cause major congenital neuronal abnormalities. In the present study, we evaluated neuropathological consequences of fetal ZIKV exposure in rhesus macaques, a highly translatable animal model for human neural development. Quantitative neuroanatomical analyses of the nearly full-term brains of fetuses infected with ZIKV at gestational days 50, 64, and 90, and three procedure-matched sham-inoculated controls were carried out. Whole tissue sections across a complete cerebral hemisphere were evaluated using immunohistochemical and neuroanatomical staining techniques to detect virus localization, identify affected cell types and evaluate gross neuroanatomical abnormalities. None of the subjects were microcephalic. Immunohistochemical staining revealed the presence of ZIKV in the frontal lobe, which contained activated microglia and showed increased apoptosis of immature neurons. ZIKV-infected animals exhibited macrostructural changes within the occipital lobe, including a reduction in gyrification as well as a higher proportion of white matter. Finally, the ZIKV-infected subjects had abnormalities throughout the visual pathway, including disorganization within the lateral geniculate nucleus (LGN) and primary visual cortex (V1). Regional differences tracked with the temporal patterns of the developing brain and likely reflect the neural progenitor cell tropism ZIKV exhibits – painting a picture of inflammatory processes related to viral infiltration sweeping through the cortex, followed by a wave of cell death resulting in morphological changes. These findings may help explain why some infants born with normal sized heads during the ZIKV epidemic manifest developmental challenges as they age, and ultimately may contribute to developing effective treatments and interventions. One sentence summary Macaque fetuses infected with Zika virus show both macro- and micro-scale neuropathological abnormalities, including decreased gyrencephality, relative increases in cortical white matter, activation of glia, and increased apoptosis.
    Date: 2020-11-11
    Authors: Seelke AMH, Beckman D, Bennett J, Dougherty P, Van Rompay KKA, Keesler RI, Pesavento PA, Coffey LL, Morrison JH, Bliss-Moreau E.
    Ref: bioRxiv
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