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bioRxiv · 10.1101/2020.10.19.344911

SARS-CoV-2 genome-wide mapping of CD8 T cell recognition reveals strong immunodominance and substantial CD8 T cell activation in COVID-19 patients

Saini, S. K.·Hersby, D. S.·Tamhane, T.·Povlsen, H. R.·Amaya Hernandez, S. P.·Nielsen, M.·Gang, A. O.·Hadrup, S. R.
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Abstract

To understand the CD8+ T cell immunity related to viral protection and disease severity in COVID-19, we evaluated the complete SARS-CoV-2 genome (3141 MHC-I binding peptides) to identify immunogenic T cell epitopes, and determine the level of CD8+ T cell involvement using DNA-barcoded peptide-major histocompatibility complex (pMHC) multimers. COVID-19 patients showed strong T cell responses, with up to 25% of all CD8+ lymphocytes specific to SARS-CoV-2-derived immunodominant epitopes, derived from ORF1 (open reading frame 1), ORF3, and Nucleocapsid (N) protein. A strong signature of T cell activation was observed in COVID-19 patients, while no T cell activation was seen in the non-exposed and high exposure risk healthy donors. Interestingly, patients with severe disease displayed the largest T cell populations with a strong activation profile. These results will have important implications for understanding the T cell immunity to SARS-CoV-2 infection, and how T cell immunity might influence disease development.

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Saini, S. K., Hersby, D. S., Tamhane, T., Povlsen, H. R., Amaya Hernandez, S. P., Nielsen, M., Gang, A. O., Hadrup, S. R.. 2020-10-19. SARS-CoV-2 genome-wide mapping of CD8 T cell recognition reveals strong immunodominance and substantial CD8 T cell activation in COVID-19 patients. https://doi.org/10.1101/2020.10.19.344911

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