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bioRxiv · 10.1101/2020.11.09.374082

SARS-CoV-2 epitope mapping on microarrays highlights strong immune-response to N protein region

Musico, A.·Frigerio, R.·Mussida, A.·Barzon, L.·Sinigaglia, A.·Riccetti, S.·Gobbi, F.·Piubelli, C.·Bergamaschi, G.·Chiari, M.·Gori, A.·Cretich, M.
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Abstract

A workflow for SARS-CoV-2 epitope discovery on peptide microarrays is herein reported. The process started with a proteome-wide screening of immunoreactivity based on the use of a high-density microarray followed by a refinement and validation phase on a restricted panel of probes using microarrays with tailored peptide immobilization through a click-based strategy. Progressively larger, independent cohorts of Covid-19 positive sera were tested in the refinement processes, leading to the identification of immunodominant regions on SARS-CoV-2 Spike (S), Nucleocapsid (N) protein and Orf1ab polyprotein. A summary study testing 50 serum samples highlighted an epitope of the N protein (region 155-171) providing 92% sensitivity and 100% specificity of IgG detection in Covid-19 samples thus being a promising candidate for rapid implementation in serological tests.

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Musico, A., Frigerio, R., Mussida, A., Barzon, L., Sinigaglia, A., Riccetti, S., Gobbi, F., Piubelli, C., Bergamaschi, G., Chiari, M., Gori, A., Cretich, M.. 2020-11-09. SARS-CoV-2 epitope mapping on microarrays highlights strong immune-response to N protein region. https://doi.org/10.1101/2020.11.09.374082

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