Durability of SARS-CoV-2-specific T cell responses at 12-months post-infection

Lu, Zhongyan; Laing, Eric D.; Pena-Damata, Jarina; Pohida, Katherine; Tso, Marana S.; Samuels, Emily C.; Epsi, Nusrat J.; Dorjbal, Batsukh; Lake, Camille; Richard, Stephanie A.; Maves, Ryan C.; Lindholm, David A.; Rozman, Julia; English, Caroline; Huprikar, Nikhil; Mende, Katrin; Colombo, Rhonda E.; Colombo, Christopher J.; Broder, Christopher C.; Ganesan, Anuradha; Lanteri, Charlotte A.; Agan, Brian K.; Tribble, David; Simons, Mark P.; Dalgard, Clifton L.; Blair, Paul W.; Chenoweth, Josh; Pollett, Simon D.; Snow, Andrew L.; Burgess, Timothy H.; Malloy, Allison M.W.

Background Characterizing the longevity and quality of cellular immune responses to SARS-CoV-2 is critical to understanding immunologic approaches to protection against COVID-19. Prior studies suggest SARS-CoV-2-specific T cells are present in peripheral blood 10 months after infection. Further analysis of the function, durability, and diversity of the cellular response long after natural infection, over a wider range of ages and disease phenotypes, is needed to further identify preventative and therapeutic interventions. Methods We identified participants in our multi-site longitudinal, prospective cohort study 12-months post SARS-CoV-2 infection representing a range of disease severity. We investigated the function, phenotypes, and frequency of T cells specific for SARS-CoV-2 using intracellular cytokine staining and spectral flow cytometry. In parallel, the magnitude of SARS-CoV-2-specific antibodies was compared. Results SARS-CoV-2-specific antibodies and T cells were detected at 12-months post-infection. Severity of acute illness was associated with higher frequencies of SARS-CoV-2-specific CD4 T cells and antibodies at 12-months. In contrast, polyfunctional and cytotoxic T cells responsive to SARS-CoV-2 were identified in participants over a wide spectrum of disease severity. Conclusions Our data show that SARS-CoV-2 infection induces polyfunctional memory T cells detectable at 12-months post-infection, with higher frequency noted in those who originally experienced severe disease.