tetano
Editor, Senior Moderator
Vaccines (Basel)
. 2021 Jan 11;9(1):E35.
doi: 10.3390/vaccines9010035.
SARS-CoV-2 Epitope Mapping on Microarrays Highlights Strong Immune-Response to N Protein Region
Angelo Music?[SUP] 1 [/SUP], Roberto Frigerio[SUP] 1 [/SUP], Alessandro Mussida[SUP] 1 [/SUP], Luisa Barzon[SUP] 2 [/SUP], Alessandro Sinigaglia[SUP] 2 [/SUP], Silvia Riccetti[SUP] 2 [/SUP], Federico Gobbi[SUP] 3 [/SUP], Chiara Piubelli[SUP] 3 [/SUP], Greta Bergamaschi[SUP] 1 [/SUP], Marcella Chiari[SUP] 1 [/SUP], Alessandro Gori[SUP] 1 [/SUP], Marina Cretich[SUP] 1 [/SUP]
Affiliations
Abstract
A workflow for rapid 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 155-71) providing good diagnostic performance in discriminating Covid-19 positive vs. healthy individuals. Using this epitope, 92% sensitivity and 100% specificity were reached for IgG detection in Covid-19 samples, and no cross-reactivity with common cold coronaviruses was detected. Likewise, IgM immunoreactivity in samples collected within the first month after symptoms onset showed discrimination ability. Overall, epitope 155-171 from N protein represents a promising candidate for further development and rapid implementation in serological tests.
Keywords: Covid-19; SARS-CoV-2; click chemistry; epitope mapping; peptide microarrays; serological test.
. 2021 Jan 11;9(1):E35.
doi: 10.3390/vaccines9010035.
SARS-CoV-2 Epitope Mapping on Microarrays Highlights Strong Immune-Response to N Protein Region
Angelo Music?[SUP] 1 [/SUP], Roberto Frigerio[SUP] 1 [/SUP], Alessandro Mussida[SUP] 1 [/SUP], Luisa Barzon[SUP] 2 [/SUP], Alessandro Sinigaglia[SUP] 2 [/SUP], Silvia Riccetti[SUP] 2 [/SUP], Federico Gobbi[SUP] 3 [/SUP], Chiara Piubelli[SUP] 3 [/SUP], Greta Bergamaschi[SUP] 1 [/SUP], Marcella Chiari[SUP] 1 [/SUP], Alessandro Gori[SUP] 1 [/SUP], Marina Cretich[SUP] 1 [/SUP]
Affiliations
- PMID: 33440622
- DOI: 10.3390/vaccines9010035
Abstract
A workflow for rapid 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 155-71) providing good diagnostic performance in discriminating Covid-19 positive vs. healthy individuals. Using this epitope, 92% sensitivity and 100% specificity were reached for IgG detection in Covid-19 samples, and no cross-reactivity with common cold coronaviruses was detected. Likewise, IgM immunoreactivity in samples collected within the first month after symptoms onset showed discrimination ability. Overall, epitope 155-171 from N protein represents a promising candidate for further development and rapid implementation in serological tests.
Keywords: Covid-19; SARS-CoV-2; click chemistry; epitope mapping; peptide microarrays; serological test.