Robust T cell immunity in convalescent individuals with asymptomatic or mild COVID-19

Sekine, T.; Perez-Potti, A.; Rivera-Ballesteros, O.; Straling, K.; Gorin, J.-B.; Olsson, A.; Llewellyn-Lacey, S.; Kamal, H.; Bogdanovic, G.; Muschiol, S.; Wulliman, D. J.; Kammann, T.; Emgard, J.; Parrot, T.; Folkesson, E.; Rooyackers, O.; Eriksson, L. I.; Sonnerborg, A.; Allander, T.; Albert, J.; Nielsen, M.; Klingstrom, J.; Gredmark-Russ, S.; Bjorkstrom, N. K.; Sandberg, J. K.; Price, D. A.; Ljunggren, H.-G.; Aleman, S.; Buggert, M.; Karolinska COVID-19 Study Group,

doi:10.1101/2020.06.29.174888

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bioRxiv · 10.1101/2020.06.29.174888

Robust T cell immunity in convalescent individuals with asymptomatic or mild COVID-19

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Abstract

ABSTRACTSARS-CoV-2-specific memory T cells will likely prove critical for long-term immune protection against COVID-19. We systematically mapped the functional and phenotypic landscape of SARS-CoV-2-specific T cell responses in a large cohort of unexposed individuals as well as exposed family members and individuals with acute or convalescent COVID-19. Acute phase SARS-CoV-2-specific T cells displayed a highly activated cytotoxic phenotype that correlated with various clinical markers of disease severity, whereas convalescent phase SARS-CoV-2-specific T cells were polyfunctional and displayed a stem-like memory phenotype. Importantly, SARS-CoV-2-specific T cells were detectable in antibody-seronegative family members and individuals with a history of asymptomatic or mild COVID-19. Our collective dataset shows that SARS-CoV-2 elicits robust memory T cell responses akin to those observed in the context of successful vaccines, suggesting that natural exposure or infection may prevent recurrent episodes of severe COVID-19 also in seronegative individuals.Competing Interest StatementThe authors have declared no competing interest.View Full Text

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Sekine, T., Perez-Potti, A., Rivera-Ballesteros, O., Straling, K., Gorin, J.-B., Olsson, A., Llewellyn-Lacey, S., Kamal, H., Bogdanovic, G., Muschiol, S., Wulliman, D. J., Kammann, T., Emgard, J., Parrot, T., Folkesson, E., Rooyackers, O., Eriksson, L. I., Sonnerborg, A., Allander, T., Albert, J., Nielsen, M., Klingstrom, J., Gredmark-Russ, S., Bjorkstrom, N. K., Sandberg, J. K., Price, D. A., Ljunggren, H.-G., Aleman, S., Buggert, M., Karolinska COVID-19 Study Group,. 2020-06-29. Robust T cell immunity in convalescent individuals with asymptomatic or mild COVID-19. https://doi.org/10.1101/2020.06.29.174888

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