Comparison of Four SARS-CoV-2 Neutralization Assays

Neutralizing antibodies are a major correlate of protection for many viruses including the novel coronavirus SARS-CoV-2. Thus, vaccine candidates should potently induce neutralizing antibodies to render effective protection from infection. A variety of in vitro assays for the detection of SARS-CoV-2 neutralizing antibodies has been described. However, validation of the different assays against each other is important to allow comparison of different studies. Here, we compared four different SARS-CoV-2 neutralization assays using the same set of patient samples. Two assays used replication competent SARS-CoV-2, a focus forming assay and a TCID50-based assay, while the other two assays used replication defective lentiviral or vesicular stomatitis virus (VSV)-based particles pseudotyped with SARS-CoV-2 spike. All assays were robust and produced highly reproducible neutralization titers. Titers of neutralizing antibodies correlated well between the different assays and with the titers of SARS-CoV-2 S-protein binding antibodies detected in an ELISA. Our study showed that commonly used SARS-CoV-2 neutralization assays are robust and that results obtained with different assays are comparable.

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Neutralizing activity of Sputnik V vaccine sera against SARS-CoV-2 variants

10.21203/rs.3.rs-400230/v1 ◽

2021 ◽

Author(s):

Satoshi Ikegame ◽

Mohammed Siddiquey ◽

Chuan-Tien Hung ◽

Griffin Haas ◽

Luca Brambilla ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Cell Line ◽

Vesicular Stomatitis Virus ◽

Neutralizing Antibodies ◽

Vaccine Development ◽

The Novel ◽

Serum Samples ◽

Egfp Reporter ◽

Vesicular Stomatitis ◽

Reduced Activity

Abstract The novel pandemic betacoronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected at least 120 million people since its identification as the cause of a December 2019 viral pneumonia outbreak in Wuhan, China1,2. Despite the unprecedented pace of vaccine development, with six vaccines already in use worldwide, the emergence of SARS-CoV-2 ‘variants of concern’ (VOC) across diverse geographic locales have prompted re-evaluation of strategies to achieve universal vaccination3. All three officially designated VOC carry Spike (S) polymorphisms thought to enable escape from neutralizing antibodies elicited during initial waves of the pandemic4–8. Here, we characterize the biological consequences of the ensemble of S mutations present in VOC lineages B.1.1.7 (501Y.V1) and B.1.351 (501Y.V2). Using a replication-competent EGFP-reporter vesicular stomatitis virus (VSV) system, rcVSV-CoV2-S, which encodes S from SARS coronavirus 2 in place of VSV-G, and coupled with a clonal HEK-293T ACE2 TMPRSS2 cell line optimized for highly efficient S-mediated infection, we determined that only 1 out of 12 serum samples from a cohort of recipients of the Gamaleya Sputnik V Ad26 / Ad5 vaccine showed effective neutralization (IC90) of rcVSV-CoV2-S: B.1.351 at full serum strength. The same set of sera efficiently neutralized S from B.1.1.7 and showed only moderately reduced activity against S carrying the E484K substitution alone. Taken together, our data suggest that control of some emergent SARS-CoV-2 variants may benefit from updated vaccines.

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Rapid in vitro assays for screening neutralizing antibodies and antivirals against SARS-CoV-2

10.1101/2020.07.22.216648 ◽

2020 ◽

Cited By ~ 2

Author(s):

Jun-Gyu Park ◽

Fatai S. Oladduni ◽

Kevin Chiem ◽

Chengjin Ye ◽

Michael Pipenbrink ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Neutralizing Antibodies ◽

Health Impact ◽

In Vitro Assays ◽

Global Pandemic ◽

Novel Coronavirus ◽

Human Infections ◽

Identification And Characterization

AbstractTowards the end of 2019, a novel coronavirus (CoV) named severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), genetically similar to severe acute respiratory syndrome coronavirus-1 (SARS-CoV-1), emerged in Wuhan, Hubei province of China, and has been responsible of coronavirus disease 2019 (COVID-19) in humans. Since its first report, SARS-CoV-2 has resulted in a global pandemic, with over 10 million human infections and over 560,000 deaths reported worldwide at the end of June 2020. Currently, there are no United States (US) Food and Drug Administration (FDA)-approved vaccines and/or antivirals licensed against SARS-CoV-2, and the high economical and health impact of SARS-CoV-2 has placed global pressure on the scientific community to identify effective prophylactic and therapeutic treatments for the treatment of SARS-CoV-2 infection and associated COVID-19 disease. While some compounds have been already reported to reduce SARS-CoV-2 infection and a handful of monoclonal antibodies (mAbs) have been described that neutralize SARS-CoV-2, there is an urgent need for the development and standardization of assays which can be used in high through-put screening (HTS) settings to identify new antivirals and/or neutralizing mAbs against SARS-CoV-2. Here, we described a rapid, accurate and highly reproducible plaque reduction microneutralization (PRMNT) assay that can be quickly adapted for the identification and characterization of both neutralizing mAbs and antivirals against SARS-CoV-2. Importantly, our MNA is compatible with HTS settings to interrogate large and/or complex libraries of mAbs and/or antivirals to identify those with neutralizing and/or antiviral activity, respectively, against SARS-CoV-2.

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Robust neutralization assay based on SARS-CoV-2 S-bearing vesicular stomatitis virus (VSV) pseudovirus and ACE2-overexpressed BHK21 cells

10.1101/2020.04.08.026948 ◽

2020 ◽

Cited By ~ 13

Author(s):

Hua-Long Xiong ◽

Yang-Tao Wu ◽

Jia-Li Cao ◽

Ren Yang ◽

Jian Ma ◽

...

Keyword(s):

Vesicular Stomatitis Virus ◽

Neutralizing Antibodies ◽

Neutralization Assay ◽

Cell Number ◽

New Drugs ◽

Human Society ◽

Angiotensin Converting Enzyme 2 ◽

Global Pandemic ◽

Vesicular Stomatitis

AbstractThe global pandemic of Coronavirus disease 2019 (COVID-19) is a disaster for human society. A convenient and reliable in vitro neutralization assay is very important for the development of neutralizing antibodies, vaccines and other inhibitors. In this study, G protein-deficient vesicular stomatitis virus (VSVdG) bearing full-length and truncated spike (S) protein of SARS-CoV-2 were evaluated. The virus packaging efficiency of VSV-SARS-CoV-2-Sdel18 (S with C-terminal 18 amino acid truncation) is much higher than VSV-SARS-CoV-2-S. A neutralization assay for antibody screening and serum neutralizing titer quantification was established based on VSV-SARS-CoV-2-Sdel18 pseudovirus and human angiotensin-converting enzyme 2 (ACE2) overexpressed BHK21 cell (BHK21-hACE2). The experimental results can be obtained by automatically counting EGFP positive cell number at 12 hours after infection, making the assay convenient and high-throughput. The serum neutralizing titer of COVID-19 convalescent patients measured by VSV-SARS-CoV-2-Sdel18 pseudovirus assay has a good correlation with live SARS-CoV-2 assay. Seven neutralizing monoclonal antibodies targeting receptor binding domain (RBD) of SARS-CoV-2-S were obtained. This efficient and reliable pseudovirus assay model could facilitate the development of new drugs and vaccines.

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Ethanol susceptibility of SARS-CoV-2 and other enveloped viruses

10.21203/rs.3.rs-379468/v1 ◽

2021 ◽

Author(s):

Toshihito Nomura ◽

Tanuza Nazmul ◽

Reiko Yoshimoto ◽

Akifumi Higashiura ◽

Kosuke Oda ◽

...

Keyword(s):

Influenza Virus ◽

Vesicular Stomatitis Virus ◽

Newcastle Disease ◽

Ethanol Concentration ◽

Effective Concentration ◽

The Novel ◽

Enveloped Viruses ◽

The Family ◽

Vesicular Stomatitis ◽

Novel Coronavirus

Abstract Ethanol is an effective disinfectant against the novel coronavirus SARS-CoV-2. However, its effective concentration has not been shown, and we therefore analyzed the effects of different concentrations of ethanol on SARS-CoV-2. When SARS-CoV-2 was treated with varying ethanol concentrations and examined for changes in infectivity, the ethanol concentration at which 99% of the infectious titers were reduced was 24.3%(w/w) [30.0%(v/v)]. For reference, ethanol susceptibility was also examined with other envelope viruses, including influenza virus, vesicular stomatitis virus in the family Rhabdoviridae, and Newcastle disease virus in the family Paramyxoviridae, and the 99% inhibitory concentrations were found to be 28.8%(w/w) [34.8%(v/v)], 24.0%(w/w) [29.2%(v/v)], and 13.4%(w/w) [16.5%(v/v)], respectively. Some differences from SARS-CoV-2 were observed, but the differences were not significant. It was concluded that ethanol at a concentration of 30%(w/w) [36.2%(v/v)] almost completely inactivates SARS-CoV-2.

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Qualitatively distinct modes of Sputnik V vaccine-neutralization escape by SARS-CoV-2 Spike variants

10.1101/2021.03.31.21254660 ◽

2021 ◽

Author(s):

Satoshi Ikegame ◽

Mohammed N. A. Siddiquey ◽

Chuan-Tien Hung ◽

Griffin Haas ◽

Luca Brambilla ◽

...

Keyword(s):

Vesicular Stomatitis Virus ◽

Neutralizing Antibodies ◽

Response Curve ◽

Vaccine Development ◽

Herd Immunity ◽

The Novel ◽

Serum Samples ◽

Egfp Reporter ◽

Vesicular Stomatitis ◽

Reduced Activity

The novel pandemic betacoronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected at least 120 million people since its identification as the cause of a December 2019 viral pneumonia outbreak in Wuhan, China. Despite the unprecedented pace of vaccine development, with six vaccines already in use worldwide, the emergence of SARS-CoV-2 variants of concern (VOC) across diverse geographic locales suggests herd immunity may fail to eliminate the virus. All three officially designated VOC carry Spike (S) polymorphisms thought to enable escape from neutralizing antibodies elicited during initial waves of the pandemic. Here, we characterize the biological consequences of the ensemble of S mutations present in VOC lineages B.1.1.7 (501Y.V1) and B.1.351 (501Y.V2). Using a replication-competent EGFP-reporter vesicular stomatitis virus (VSV) system, rcVSV-CoV2-S, which encodes S from SARS coronavirus 2 in place of VSV-G, coupled with a clonal HEK-293T ACE2 TMPRSS2 cell line optimized for highly efficient S-mediated infection, we determined that 8 out of 12 (75%) of serum samples from 12 recipients of the Russian Sputnik V Ad26 / Ad5 vaccine showed dose response curve slopes indicative of failure to neutralize rcVSV-CoV2-S: B.1.351. The same set of sera efficiently neutralized S from B.1.1.7 and showed only moderately reduced activity against S carrying the E484K substitution alone. Taken together, our data suggest that control of emergent SARS-CoV-2 variants may benefit from updated vaccines.

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Ethanol susceptibility of SARS-CoV-2 and other enveloped viruses

10.21203/rs.3.rs-379468/v3 ◽

2021 ◽

Author(s):

Toshihito Nomura ◽

Tanuza Nazmul ◽

Reiko Yoshimoto ◽

Akifumi Higashiura ◽

Kosuke Oda ◽

...

Keyword(s):

Influenza Virus ◽

Vesicular Stomatitis Virus ◽

Newcastle Disease ◽

Ethanol Concentration ◽

Effective Concentration ◽

The Novel ◽

Enveloped Viruses ◽

The Family ◽

Vesicular Stomatitis ◽

Novel Coronavirus

Abstract Ethanol is an effective disinfectant against the novel coronavirus SARS-CoV-2. However, its effective concentration has not been shown, and we therefore analyzed the effects of different concentrations of ethanol on SARS-CoV-2. When SARS-CoV-2 was treated with varying ethanol concentrations and examined for changes in infectivity, the ethanol concentration at which 99% of the infectious titers were reduced was 24.1%(w/w) [29.3%(v/v)]. For reference, ethanol susceptibility was also examined with other envelope viruses, including influenza virus, vesicular stomatitis virus in the family Rhabdoviridae, and Newcastle disease virus in the family Paramyxoviridae, and the 99% inhibitory concentrations were found to be 28.8%(w/w) [34.8%(v/v)], 24.0%(w/w) [29.2%(v/v)], and 13.3%(w/w) [16.4%(v/v)], respectively. Some differences from SARS-CoV-2 were observed, but the differences were not significant. It was concluded that ethanol at a concentration of 30%(w/w) [36.2%(v/v)] almost completely inactivates SARS-CoV-2.

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Ethanol susceptibility of SARS-CoV-2 and other enveloped viruses

10.21203/rs.3.rs-379468/v2 ◽

2021 ◽

Author(s):

Toshihito Nomura ◽

Tanuza Nazmul ◽

Reiko Yoshimoto ◽

Akifumi Higashiura ◽

Kosuke Oda ◽

...

Keyword(s):

Influenza Virus ◽

Vesicular Stomatitis Virus ◽

Newcastle Disease ◽

Ethanol Concentration ◽

Effective Concentration ◽

The Novel ◽

Enveloped Viruses ◽

The Family ◽

Vesicular Stomatitis ◽

Novel Coronavirus

Abstract Ethanol is an effective disinfectant against the novel coronavirus SARS-CoV-2. However, its effective concentration has not been shown, and we therefore analyzed the effects of different concentrations of ethanol on SARS-CoV-2. When SARS-CoV-2 was treated with varying ethanol concentrations and examined for changes in infectivity, the ethanol concentration at which 99% of the infectious titers were reduced was 24.3%(w/w) [30.0%(v/v)]. For reference, ethanol susceptibility was also examined with other envelope viruses, including influenza virus, vesicular stomatitis virus in the family Rhabdoviridae, and Newcastle disease virus in the family Paramyxoviridae, and the 99% inhibitory concentrations were found to be 28.8%(w/w) [34.8%(v/v)], 24.0%(w/w) [29.2%(v/v)], and 13.3%(w/w) [16.5%(v/v)], respectively. Some differences from SARS-CoV-2 were observed, but the differences were not significant. It was concluded that ethanol at a concentration of 30%(w/w) [36.2%(v/v)] almost completely inactivates SARS-CoV-2.

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The Political Impact of Affective Polarization: How Partisan Animus Shapes COVID-19 Attitudes

10.31234/osf.io/ztgpn ◽

2020 ◽

Cited By ~ 1

Author(s):

James Druckman ◽

Samara Klar ◽

Yanna Krupnikov ◽

Matthew Levendusky ◽

John B. Ryan

Keyword(s):

21St Century ◽

American Politics ◽

The Other ◽

Policy Discourse ◽

The Political ◽

The Novel ◽

Political Impact ◽

Novel Coronavirus ◽

Citizens Attitudes

Affective polarization is a defining feature of 21st century American politics—partisans harbor considerable dislike and distrust of those from the other party. Does this animus have consequences for citizens’ opinions? Such effects would highlight not only the consequences of polarization, but also shed new light onto how citizens form preferences more generally. Normally, this question is intractable, but the outbreak of the novel coronavirus allows us to answer it. We find that affective polarization powerfully shapes citizens’ attitudes about the pandemic, as well as the actions they have taken in response to it. However, these effects are conditional on the local severity of the outbreak, as the effects decline in areas with high caseloads—threat vitiates partisan reasoning. Our results clarify that closing the divide on important issues requires not just policy discourse but also attempts to reduce inter-partisan hostility.

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The Antiviral and Antimalarial Drug Repurposing in Quest of Chemotherapeutics to Combat COVID-19 Utilizing Structure-Based Molecular Docking

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323999200824115536 ◽

2020 ◽

Vol 23 ◽

Author(s):

Sisir Nandi ◽

Mohit Kumar ◽

Mridula Saxena ◽

Anil Kumar Saxena

Keyword(s):

Molecular Docking ◽

In Silico ◽

Drug Repurposing ◽

Clinical Settings ◽

The Novel ◽

In Silico Docking ◽

Biochemical Mechanisms ◽

Novel Coronavirus ◽

In Silico Molecular Docking

Background: The novel coronavirus disease (COVID-19) is caused by a new strain (SARS-CoV-2) erupted in 2019. Nowadays, it is a great threat that claims uncountable lives worldwide. There is no specific chemotherapeutics developed yet to combat COVID-19. Therefore, scientists have been devoted in the quest of the medicine that can cure COVID- 19. Objective: Existing antivirals such as ASC09/ritonavir, lopinavir/ritonavir with or without umifenovir in combination with antimalarial chloroquine or hydroxychloroquine have been repurposed to fight the current coronavirus epidemic. But exact biochemical mechanisms of these drugs towards COVID-19 have not been discovered to date. Method: In-silico molecular docking can predict the mode of binding to sort out the existing chemotherapeutics having a potential affinity towards inhibition of the COVID-19 target. An attempt has been made in the present work to carry out docking analyses of 34 drugs including antivirals and antimalarials to explain explicitly the mode of interactions of these ligands towards the COVID-19protease target. Results: 13 compounds having good binding affinity have been predicted towards protease binding inhibition of COVID-19. Conclusion: Our in silico docking results have been confirmed by current reports from clinical settings through the citation of suitable experimental in vitro data available in the published literature.

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Synthetic and semi-synthetic drugs as promising therapeutic option for the treatment of COVID-19

Mini-Reviews in Medicinal Chemistry ◽

10.2174/1389557520666201204162103 ◽

2020 ◽

Vol 20 ◽

Author(s):

Ekta Shirbhate ◽

Preeti Patel ◽

Vijay K Patel ◽

Ravichandran Veerasamy ◽

Prabodh C Sharma ◽

...

Keyword(s):

Therapeutic Option ◽

Antiviral Treatment ◽

The Novel ◽

Clinical Experiences ◽

Synthetic Compounds ◽

Synthetic Drugs ◽

Global Pandemic ◽

The World ◽

Novel Coronavirus

: The novel coronavirus disease-19 (COVID-19), a global pandemic that emerged from Wuhan, China has today travelled all around the world, so far 216 countries or territories with 21,732,472 people infected and 770,866 deaths globally (as per WHO COVID-19 update dated August 18, 2020). Continuous efforts are being made to repurpose the existing drugs and develop vaccines for combating this infection. Despite, to date, no certified antiviral treatment or vaccine prevails. Although, few candidates have displayed their efficacy in in vitro studies and are being repurposed for COVID-19 treatment. This article summarizes synthetic and semi-synthetic compounds displaying potent activity in their clinical experiences or studies against COVID-19 and also focuses on mode of action of drugs being repositioned against COVID-19.

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