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bioRxiv · 10.1101/2022.10.14.512324

SARS-CoV-2 multi-antigen protein microarray for detailed characterization of antibody responses in COVID-19 patients

Celikgil, A.·Massimi, A. B.·Nakouzi, A.·Herrera, N. G.·Morano, N. C.·Lee, J. H.·Yoon, H. a.·Garforth, S. J.·Almo, S. C.
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Abstract

Antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) target multiple epitopes on different domains of the spike protein, and other SARS-CoV-2 proteins. We developed a SARS-CoV-2 multi-antigen protein microarray with the nucleocapsid, spike and its domains (S1, S2), and variants with single (D614G, E484K, N501Y) or double substitutions (N501Y/Deletion69/70), allowing a more detailed high-throughput analysis of the antibody repertoire following infection. The assay was demonstrated to be reliable and comparable to ELISA. We analyzed antibodies from 18 COVID-19 patients and 12 recovered convalescent donors. S IgG level was higher than N IgG in most of the COVID-19 patients, receptor-binding domain of S1 showed high reactivity, but no antibodies were detected against heptad repeat domain 2 of S2. Furthermore, antibodies were detected against S variants with single and double substitutions in COVID-19 patients who were infected with SARS-CoV-2 early in the pandemic. Here we demonstrated that SARS-CoV-2 multi-antigen protein microarray is a powerful tool for detailed characterization of antibody responses, with potential utility in understanding the disease progress and assessing current vaccines and therapies against evolving SARS-CoV-2.

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Celikgil, A., Massimi, A. B., Nakouzi, A., Herrera, N. G., Morano, N. C., Lee, J. H., Yoon, H. a., Garforth, S. J., Almo, S. C.. 2022-10-16. SARS-CoV-2 multi-antigen protein microarray for detailed characterization of antibody responses in COVID-19 patients. https://doi.org/10.1101/2022.10.14.512324

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