COVID-19 vaccine booster induces a strong CD8+ T cell response against Omicron variant epitopes in HLA-A*02:01+ individuals

Nguyen, A. T.; Szeto, C.; Chatzileontiadou, D. S. M.; Tong, Z. W. M.; Dewar-Oldis, M. J.; Cooper, L.; Murdolo, L. D.; Chew, K. Y.; Lineburg, K. E.; Riboldi-Tunicliffe, A.; Williamson, R.; Gardiner, B. J.; Jayasinghe, D.; Lobos, C. A.; Ahn, Y. M.; Grant, E. J.; Smith, C.; McMahon, J.; Good-Jacobson, K. L.; Barnard, P. J.; Short, K. R.; Gras, S.

doi:10.1101/2022.01.12.473243

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bioRxiv · 10.1101/2022.01.12.473243

COVID-19 vaccine booster induces a strong CD8+ T cell response against Omicron variant epitopes in HLA-A*02:01+ individuals

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Abstract

The >30 mutated residues in the Omicron spike protein have led to its rapid classification as a new SARS-CoV-2 variant of concern. As a result, Omicron may escape from the immune system, decreasing the protection provided by COVID-19 vaccines. Preliminary data shows a weaker neutralizing antibody response to Omicron compared to the ancestral SARS-CoV-2 virus, which can be increased after a booster vaccine. Here, we report that CD8+ T cells can recognize Omicron variant epitopes presented by HLA-A*02:01 in both COVID-19 recovered and vaccinated individuals, even 6 months after infection or vaccination. Additionally, the T cell response was stronger for Omicron variant epitopes after the vaccine booster. Altogether, T cells can recognize Omicron variants, especially in vaccinated individuals after the vaccine booster. One-Sentence SummaryCD8+ T cells response against Omicron variant epitopes is stronger after the vaccine booster.

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Nguyen, A. T., Szeto, C., Chatzileontiadou, D. S. M., Tong, Z. W. M., Dewar-Oldis, M. J., Cooper, L., Murdolo, L. D., Chew, K. Y., Lineburg, K. E., Riboldi-Tunicliffe, A., Williamson, R., Gardiner, B. J., Jayasinghe, D., Lobos, C. A., Ahn, Y. M., Grant, E. J., Smith, C., McMahon, J., Good-Jacobson, K. L., Barnard, P. J., Short, K. R., Gras, S.. 2022-01-13. COVID-19 vaccine booster induces a strong CD8+ T cell response against Omicron variant epitopes in HLA-A*02:01+ individuals. https://doi.org/10.1101/2022.01.12.473243

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