Immunological memory to SARS-CoV-2 assessed for greater than six months after infection

Dan, J. M.; Mateus, J.; Kato, Y.; Hastie, K. M.; Faliti, C.; Ramirez, S. I.; Frazier, A.; Yu, E. D.; Grifoni, A.; Rawlings, S. A.; Peters, B.; Krammer, F.; Simon, V.; Saphire, E. O.; Smith, D.; Weiskopf, D.; Sette, A.; Crotty, S.

doi:10.1101/2020.11.15.383323

bioRxiv · 10.1101/2020.11.15.383323

Immunological memory to SARS-CoV-2 assessed for greater than six months after infection

Dan, J. M.·Mateus, J.·Kato, Y.·Hastie, K. M.·Faliti, C.·Ramirez, S. I.·Frazier, A.·Yu, E. D.·Grifoni, A.·Rawlings, S. A.·Peters, B.·Krammer, F.·Simon, V.·Saphire, E. O.·Smith, D.·Weiskopf, D.·Sette, A.·Crotty, S.

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Abstract

Understanding immune memory to SARS-CoV-2 is critical for improving diagnostics and vaccines, and for assessing the likely future course of the COVID-19 pandemic. We analyzed multiple compartments of circulating immune memory to SARS-CoV-2 in 254 samples from 188 COVID-19 cases, including 43 samples at [≥] 6 months post-infection. IgG to the Spike protein was relatively stable over 6+ months. Spike-specific memory B cells were more abundant at 6 months than at 1 month post symptom onset. SARS-CoV-2-specific CD4+ T cells and CD8+ T cells declined with a half-life of 3-5 months. By studying antibody, memory B cell, CD4+ T cell, and CD8+ T cell memory to SARS-CoV-2 in an integrated manner, we observed that each component of SARS-CoV-2 immune memory exhibited distinct kinetics.

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Dan, J. M., Mateus, J., Kato, Y., Hastie, K. M., Faliti, C., Ramirez, S. I., Frazier, A., Yu, E. D., Grifoni, A., Rawlings, S. A., Peters, B., Krammer, F., Simon, V., Saphire, E. O., Smith, D., Weiskopf, D., Sette, A., Crotty, S.. 2020-11-16. Immunological memory to SARS-CoV-2 assessed for greater than six months after infection. https://doi.org/10.1101/2020.11.15.383323

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