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

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.

doi:10.1101/2023.05.29.542720

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

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.

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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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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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