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bioRxiv · 10.1101/2023.05.29.542720

Development of a SARS-COV-2 monoclonal antibody panel and its applicability as a reagent in high-throughput fluorescence reduction neutralization and immunohistochemistry assays

Abstract

Since its emergence in late 2019, infection by SARS-CoV-2 (COVID-19 disease) has quickly spread worldwide, leading to a pandemic that has caused millions of deaths and huge socio-economic losses. Although vaccination against COVID-19 has significantly reduced disease mortality, it has been shown that protection wanes over time, and that circulating SARS-CoV-2 variants may escape vaccine-derived immunity. Therefore, serological studies are still necessary to assess protection in the population and better guide vaccine booster programs. A common measure of protective immunity is the presence of neutralizing antibodies (nAbs). However, the gold standard method for measuring nAbs (plaque reduction neutralization test, or PRNT) is laborious and time-consuming, limiting its large-scale applicability. In this study, we developed a high-throughput fluorescence reduction neutralization assay (FRNA) to detect SARS-CoV-2 nAbs. Because the assay relies on immunostaining, we also developed and characterized in-house monoclonal antibodies (mAbs) to lower assay costs and reduce the vulnerability of the test to reagent shortages. Using samples collected before the pandemic and from individuals vaccinated against COVID-19, we showed that the results of the FRNA we developed using commercial and in-house mAbs strongly correlated with those of the standard PRNT method while providing results in 70% less time. In addition to providing a fast, reliable, and high-throughput alternative for measuring nAbs, the FRNA can be easily customized to assess other SARS-CoV-2 variants of concern (VOCs).

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BibTeXRIS

Mattoso, G., Cataneo, A., Raboni, S. M., Nogueira, M. B., Vaz de Paula, C., Almeida, A. C., Rogerio, V., Zanchin, N., de Noronha, L., Zanluca, C., Duarte dos Santos, C. N.. 2023-05-29. Development of a SARS-COV-2 monoclonal antibody panel and its applicability as a reagent in high-throughput fluorescence reduction neutralization and immunohistochemistry assays. https://doi.org/10.1101/2023.05.29.542720

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