SARS-CoV-2-specific T cell memory is long-lasting in the majority of convalsecent COVID-19 individuals

Li, Z.; Liu, J.; Deng, H.; Yang, X.; Wang, H.; Feng, X.; Zelinskyy, G.; Trilling, M.; Sutter, K.; Lu, M.; Wang, B.; Yang, D.; Zheng, X.

doi:10.1101/2020.11.15.383463

bioRxiv · 10.1101/2020.11.15.383463

SARS-CoV-2-specific T cell memory is long-lasting in the majority of convalsecent COVID-19 individuals

Li, Z.·Liu, J.·Deng, H.·Yang, X.·Wang, H.·Feng, X.·Zelinskyy, G.·Trilling, M.·Sutter, K.·Lu, M.·Wang, B.·Yang, D.·Zheng, X.

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Abstract

An unaddressed key question in the current coronavirus disease 2019 (COVID-19) pandemic is the duration of immunity for which specific T cell responses against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are an indispensable element. Being situated in Wuhan where the pandemic initiated enables us to conduct the longest analyses of memory T cell responses against SARS-CoV-2 in COVID-19 convalescent individuals (CIs). Magnitude and breadth of SARS-CoV-2 memory CD4 and CD8 T cell responses were heterogeneous between patients but robust responses could be detected up to 9 months post disease onset in most CIs. Loss of memory CD4 and CD8 T cell responses were observed in only 16.13% and 25.81% of CIs, respectively. Thus, the overall magnitude and breadth of memory CD4 and CD8 T cell responses were quite stable and not inversely correlated with the time from disease onset. Interestingly, the only significant decrease in the response was found for memory CD4 T cells in the first 6-month post COVID-19 disease onset. Longitudinal analyses revealed that the kinetics of SARS-CoV-2 memory CD4 and CD8 T cell responses were quite heterogenous between patients. Loss of memory CD4 T cell responses was observed more frequently in asymptomatic cases than after symptomatic COVID-19. Interestingly, the few CIs in which SARS-CoV-2-specific IgG responses disappeared showed more durable memory CD4 T cell responses than CIs who remained IgG-positive for month. Collectively, we provide the first comprehensive characterization of the long-term memory T cell response in CIs, suggesting that SARS-CoV-2-specific T cell immunity is long-lasting in the majority of individuals.

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Li, Z., Liu, J., Deng, H., Yang, X., Wang, H., Feng, X., Zelinskyy, G., Trilling, M., Sutter, K., Lu, M., Wang, B., Yang, D., Zheng, X.. 2020-11-16. SARS-CoV-2-specific T cell memory is long-lasting in the majority of convalsecent COVID-19 individuals. https://doi.org/10.1101/2020.11.15.383463

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