High-throughput detection of antibodies targeting the SARS-CoV-2 Spike in longitudinal convalescent plasma samples

Anand, S. P.; Prevost, J.; Richard, J.; Perreault, J.; Tremblay, T.; Drouin, M.; Fournier, M.-J.; Lewin, A.; Bazin, R.; Finzi, A.

doi:10.1101/2020.10.20.346783

bioRxiv · 10.1101/2020.10.20.346783

High-throughput detection of antibodies targeting the SARS-CoV-2 Spike in longitudinal convalescent plasma samples

Anand, S. P.·Prevost, J.·Richard, J.·Perreault, J.·Tremblay, T.·Drouin, M.·Fournier, M.-J.·Lewin, A.·Bazin, R.·Finzi, A.

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Abstract

BackgroundThe SARS-CoV-2 virus is the cause of the ongoing coronavirus disease 2019 (COVID-19) pandemic, infecting millions of people and causing more than a million deaths. The SARS-CoV-2 Spike glycoproteins mediate viral entry and represent the main target for antibody responses. Humoral responses were shown to be important for preventing and controlling infection by coronaviruses. A promising approach to reduce the severity of COVID-19 is the transfusion of convalescent plasma. However, longitudinal studies revealed that the level of antibodies targeting the receptor-binding domain (RBD) of the SARS-CoV-2 Spike declines rapidly after the resolution of the infection. Study Design and MethodsTo extend this observation beyond the RBD domain, we performed a longitudinal analysis of the persistence of antibodies targeting the full-length SARS-CoV-2 Spike in the plasma from 15 convalescent donors. We generated a 293T cell line constitutively expressing the SARS-CoV-2 Spike and used it to develop a high-throughput flow cytometry-based assay to detect SARS-CoV-2 Spike specific antibodies in the plasma of convalescent donors. Results and ConclusionWe found that the level of antibodies targeting the full-length SARS-CoV-2 Spike declines gradually after the resolution of the infection. This decline was not related to the number of donations, but strongly correlated with the decline of RBD-specific antibodies and the number of days post-symptom onset. These findings help to better understand the decline of humoral responses against the SARS-CoV-2 Spike and provide important information on when to collect plasma after recovery from active infection for convalescent plasma transfusion.

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Anand, S. P., Prevost, J., Richard, J., Perreault, J., Tremblay, T., Drouin, M., Fournier, M.-J., Lewin, A., Bazin, R., Finzi, A.. 2020-10-20. High-throughput detection of antibodies targeting the SARS-CoV-2 Spike in longitudinal convalescent plasma samples. https://doi.org/10.1101/2020.10.20.346783

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