SARS-CoV-2 neutralization and serology testing of COVID-19 convalescent plasma from donors with non-severe disease

Gniadek, T. J.; Thiede, J. M.; Matchett, W. E.; Gress, A. R.; Pape, K. A.; Jenkins, M. K.; Menachery, V. D.; Langlois, R. A.; Bold, T. D.

doi:10.1101/2020.08.07.242271

bioRxiv · 10.1101/2020.08.07.242271

SARS-CoV-2 neutralization and serology testing of COVID-19 convalescent plasma from donors with non-severe disease

Gniadek, T. J.·Thiede, J. M.·Matchett, W. E.·Gress, A. R.·Pape, K. A.·Jenkins, M. K.·Menachery, V. D.·Langlois, R. A.·Bold, T. D.

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Abstract

We determined the antigen binding activity of convalescent plasma units from 47 individuals with a history of non-severe COVID-19 using three clinical diagnostic serology assays (Beckman, DiaSorin, and Roche) with different SARS-CoV-2 targets. We compared these results with functional neutralization activity using a fluorescent reporter strain of SARS-CoV-2 in a microwell assay. This revealed positive correlations of varying strength (Spearman r = 0.37-0.52) between binding and neutralization. Donors age 48-75 had the highest neutralization activity. Units in the highest tertile of binding activity for each assay were enriched (75-82%) for those with the highest levels of neutralization.

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Gniadek, T. J., Thiede, J. M., Matchett, W. E., Gress, A. R., Pape, K. A., Jenkins, M. K., Menachery, V. D., Langlois, R. A., Bold, T. D.. 2020-08-10. SARS-CoV-2 neutralization and serology testing of COVID-19 convalescent plasma from donors with non-severe disease. https://doi.org/10.1101/2020.08.07.242271

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