Persistence and potency of naturally-occuring and vaccine-induced memory T cells to SARS-Cov-2 variants

The COVID-19 pandemic has led to the infection of more than 135 million people world-wide and the death of 4 million of these individuals. The development of vaccines gives us hope that we will ultimately control the pandemic. It remains to be demonstrated if mass vaccination can induce prolonged protection against reinfection in vaccinated individuals, and thus prevent virus transmission and dissemination world-wide. This collaborative project with the Coalition for Epidemic Preparedness Innovations (CEPI) proposes to evaluate if immune cells called T cells are generated and maintained in vaccinated individuals, as these T cells are essential for prolonged protection against SARS-CoV-2, the virus that induces COVID-19. Further, we propose to test if these T cells develop long-lasting immune memory and are protective against the novel and more infectious variants. Finally, we hope to identify which memory T cells are truly protective and develop simple surveillance tools to follow these memory T cells in infected or vaccinated individuals. Collectively, this project will support the development of effective and protective vaccines against coronaviruses of pandemic potential, including SARS-Cov-2.