Evaluation of Neutralizing Antibodies Against Highly Pathogenic Coronaviruses: A Detailed Protocol for a Rapid Evaluation of Neutralizing Antibodies Using Vesicular Stomatitis Virus Pseudovirus-Based Assay

Emerging highly pathogenic human coronaviruses (CoVs) represent a serious ongoing threat to the public health worldwide. The spike (S) proteins of CoVs are surface glycoproteins that facilitate viral entry into host cells via attachment to their respective cellular receptors. The S protein is believed to be a major immunogenic component of CoVs and a target for neutralizing antibodies (nAbs) and most candidate vaccines. Development of a safe and convenient assay is thus urgently needed to determine the prevalence of CoVs nAbs in the population, to study immune response in infected individuals, and to aid in vaccines and viral entry inhibitors evaluation. While live virus-based neutralization assays are used as gold standard serological methods to detect and measure nAbs, handling of highly pathogenic live CoVs requires strict bio-containment conditions in biosafety level-3 laboratories. On the other hand, use of replication-incompetent pseudoviruses bearing CoVs S proteins could represent a safe and useful method to detect nAbs in serum samples under biosafety level-2 conditions. Here, we describe a detailed protocol of a safe and convenient assay to generate vesicular stomatitis virus (VSV)-based pseudoviruses to evaluate and measure nAbs against highly pathogenic CoVs. The protocol covers methods to produce VSV pseudovirus bearing the S protein of the Middle East respiratory syndrome-CoV (MERS-CoV) and the severe acute respiratory syndrome-CoV-2 (SARS-CoV-2), pseudovirus titration, and pseudovirus neutralizing assay. Such assay could be adapted by different laboratories and researchers working on highly pathogenic CoVs without the need to handle live viruses in biosafety level-3 environment.

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Comparison of Four SARS-CoV-2 Neutralization Assays

Vaccines ◽

10.3390/vaccines9010013 ◽

2020 ◽

Vol 9 (1) ◽

pp. 13

Author(s):

Lydia Riepler ◽

Annika Rössler ◽

Albert Falch ◽

André Volland ◽

Wegene Borena ◽

...

Keyword(s):

Vesicular Stomatitis Virus ◽

Neutralizing Antibodies ◽

The Other ◽

In Vitro Assays ◽

The Novel ◽

Effective Protection ◽

Vaccine Candidates ◽

Vesicular Stomatitis ◽

Novel Coronavirus

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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Safety, Immunogenicity and Efficacy of a Recombinant Vesicular Stomatitis Virus Vectored Vaccine Against Severe Fever with Thrombocytopenia Syndrome and Heartland Bandaviruses

10.1101/2021.11.29.470508 ◽

2021 ◽

Author(s):

Phillip Hicks ◽

Jonna B. Westover ◽

Tomaz B Manzoni ◽

Brianne Roper ◽

Gabrielle L Rock ◽

...

Keyword(s):

Vesicular Stomatitis Virus ◽

Neutralizing Antibodies ◽

Genetic Manipulation ◽

Case Fatality ◽

Vaccine Platform ◽

Vesicular Stomatitis ◽

Immunocompetent Mice ◽

Vectored Vaccine ◽

Severe Fever ◽

Promising Vaccine Candidate

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a recently emerged tickborne virus in east Asia with over 8,000 confirmed cases. With a high case fatality ratio, SFTSV has been designated a high priority pathogen by the WHO and the NIAID. Despite this, there are currently no approved therapies or vaccines to treat or prevent SFTS. Vesicular stomatitis virus (VSV) represents an FDA-approved vaccine platform that has been considered for numerous viruses due to its low sero-prevalence in humans, ease in genetic manipulation and promiscuity in incorporating foreign glycoproteins into its virions. In this study, we developed a recombinant VSV (rVSV) expressing the SFTSV glycoproteins Gn/Gc (rVSV-SFTSV) and assessed its safety, immunogenicity and efficacy in mice. We demonstrate that rVSV-SFTSV is safe when given to immunocompromised animals and is not neuropathogenic when injected intracranially into young immunocompetent mice. Immunization of Ifnar-/- mice with rVSV-SFTSV resulted in high levels of neutralizing antibodies and protection against lethal SFTSV challenge. Additionally, passive transfer of sera from immunized IFNAR-/- mice into naïve animals was protective when given pre- or post-exposure. Finally, we demonstrate that immunization with rVSV-SFTSV cross protects mice against challenge with the closely related Heartland virus despite low neutralizing titers to the virus. Taken together, these data suggest that rVSV-SFTSV is a promising vaccine candidate.

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Effective screening of SARS-CoV-2 neutralizing antibodies in patient serum using lentivirus particles pseudotyped with SARS-CoV-2 spike glycoprotein

Scientific Reports ◽

10.1038/s41598-020-76135-w ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Ritesh Tandon ◽

Dipanwita Mitra ◽

Poonam Sharma ◽

Martin G. McCandless ◽

Stephen J. Stray ◽

...

Keyword(s):

Mammalian Cells ◽

Neutralizing Antibodies ◽

Transduction Efficiency ◽

Pseudotyped Virus ◽

Spike Glycoprotein ◽

Highly Pathogenic ◽

Mammalian Cell Lines ◽

Serological Studies ◽

Pathogenic Viruses ◽

Vesicular Stomatitis

Abstract Pseuodotyped particles have significant importance and use in virology as tools for studying the biology of highly pathogenic viruses in a lower biosafety environment. The biological, chemical, and serological studies of the recently emerged SARS-CoV-2 will be greatly aided by the development and optimization of a suitable pseudotyping system. Here, we pseudotyped the SARS-CoV-2 Spike glycoprotein (SPG) on a traditional retroviral (MMLV) as well as a third generation lentiviral (pLV) vector and tested the transduction efficiency in several mammalian cell lines expressing SARS-CoV-2 receptor hACE2. While MMLV pseudotyped the vesicular stomatitis virus G glycoprotein (VSV-G) efficiently, it could not pseudotype the full-length SPG. In contrast, pLV pseudotyped both glycoproteins efficiently; however, much higher titers of pLV-G particles were produced. Among all the tested mammalian cells, 293Ts expressing hACE2 were most efficiently transduced using the pLV-S system. The pLV-S particles were efficiently neutralized by diluted serum (>:640) from recently recovered COVID-19 patients who showed high SARS-CoV-2 specific IgM and IgG levels. In summary, pLV-S pseudotyped virus provides a valid screening tool for the presence of anti SARS-CoV-2 specific neutralizing antibodies in convalescent patient serum.

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Rapid Quantification of SARS-CoV-2-Neutralizing Antibodies Using Propagation-Defective Vesicular Stomatitis Virus Pseudotypes

Vaccines ◽

10.3390/vaccines8030386 ◽

2020 ◽

Vol 8 (3) ◽

pp. 386 ◽

Cited By ~ 8

Author(s):

Ferdinand Zettl ◽

Toni Luise Meister ◽

Tanja Vollmer ◽

Bastian Fischer ◽

Jörg Steinmann ◽

...

Keyword(s):

Vesicular Stomatitis Virus ◽

Neutralizing Antibodies ◽

Neutralization Test ◽

Pearson Correlation ◽

Spike Protein ◽

Virus Neutralization ◽

Pseudotype Virus ◽

Vesicular Stomatitis ◽

Level 1 ◽

Biosafety Level

Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2, a new member of the genus Betacoronavirus, is a pandemic virus, which has caused numerous fatalities, particularly in the elderly and persons with underlying morbidities. At present, there are no approved vaccines nor antiviral therapies available. The detection and quantification of SARS-CoV-2-neutralizing antibodies plays a crucial role in the assessment of the immune status of convalescent COVID-19 patients, evaluation of recombinant therapeutic antibodies, and the evaluation of novel vaccines. To detect SARS-CoV-2-neutralizing antibodies, classically, a virus-neutralization test has to be performed at biosafety level 3, considerably limiting the general use of this test. In the present work, a biosafety level 1 pseudotype virus assay based on a propagation-incompetent vesicular stomatitis virus (VSV) has been used to determine the neutralizing antibody titers in convalescent COVID-19 patients. The neutralization titers in serum of two independently analyzed patient cohorts were available within 18 h and correlated well with those obtained with a classical SARS-CoV-2 neutralization test (Pearson correlation coefficients of r = 0.929 and r = 0.939, respectively). Most convalescent COVID-19 patients had only low titers of neutralizing antibodies (ND50 < 320). The sera of convalescent COVID-19 patients also neutralized pseudotype virus displaying the SARS-CoV-1 spike protein on their surface, which is homologous to the SARS-CoV-2 spike protein. In summary, we report a robust virus-neutralization assay, which can be used at low biosafety level 1 to rapidly quantify SARS-CoV-2-neutralizing antibodies in convalescent COVID-19 patients and vaccinated individuals.

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Vesicular stomatitis virus vectors expressing avian influenza H5 HA induce cross-neutralizing antibodies and long-term protection

Virology ◽

10.1016/j.virol.2007.04.021 ◽

2007 ◽

Vol 366 (1) ◽

pp. 166-173 ◽

Cited By ~ 42

Author(s):

Jennifer A. Schwartz ◽

Linda Buonocore ◽

Anjeanette Roberts ◽

Amorsolo Suguitan ◽

Darwyn Kobasa ◽

...

Keyword(s):

Avian Influenza ◽

Vesicular Stomatitis Virus ◽

Neutralizing Antibodies ◽

Virus Vectors ◽

Vesicular Stomatitis

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A single dose of replication-competent VSV-vectored vaccine expressing SARS-CoV-2 S1 protects against virus replication in a hamster model of severe COVID-19

10.1101/2021.01.29.428442 ◽

2021 ◽

Author(s):

Delphine C. Malherbe ◽

Drishya Kurup ◽

Christoph Wirblich ◽

Adam J. Ronk ◽

Chad Mire ◽

...

Keyword(s):

Animal Model ◽

Vesicular Stomatitis Virus ◽

Neutralizing Antibodies ◽

Specific Binding ◽

Vaccine Dose ◽

Spike Protein ◽

Hamster Model ◽

Rapid Control ◽

Vesicular Stomatitis ◽

Vectored Vaccine

SUMMARYThe development of effective countermeasures against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the agent responsible for the COVID-19 pandemic, is a priority. We designed and produced ConVac, a replication-competent vesicular stomatitis virus (VSV) vaccine vector that expresses the S1 subunit of SARS-CoV-2 spike protein. We used golden Syrian hamsters as animal model of severe COVID-19 to test the efficacy of the ConVac vaccine. A single vaccine dose elicited high levels of SARS-CoV-2 specific binding and neutralizing antibodies; following intranasal challenge with SARS-CoV-2, animals were protected from weight loss and viral replication in the lungs. No enhanced pathology was observed in vaccinated animals upon challenge, but some inflammation was still detected. The data indicate rapid control of SARS-CoV-2 replication by the S1-based VSV-vectored SARS-CoV-2 ConVac vaccine.

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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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