Cellular-mediated immunity against SARS-CoV-2

Generation of adaptive immunity to SARS-CoV-2 is most likely key for protection against secondary infection. In the wake of long-lived anti-SARS-CoV-2 antibodies, cellular-mediated, T cell, responses are likely critical to dampen the severity of SARS-CoV-2 re-infection. Our specific aim in this proposal is to understand if people with COVID-19 develop durable cellular-mediated responses against SARS-CoV-2. The collection of unique longitudinal human samples together with the usage of cutting-edge single-cell methods will be the central tenet of this project proposal to answer this overall question. We are working in close collaboration with a team of clinicians and researchers at Karolinska to obtain samples longitudinally from a large cohort of patients, including those that returned from endemic areas (mostly northern Italy) and were tested PCR+ for SARS-CoV-2 despite having no to mild symptoms in early March. Based on preliminary data, we hypothesize that convalescent patients develop a functional B and T cell response against SARS-CoV-2 - i.e. immunity. Our aim is to continue the collection of samples from convalescent patients, blood donors and other patient groups during the entire 2020 and 2021 to understand if cellular-mediated immunity is more "long-lasting" than antibody responses as implicated in SARS-CoV-1 and other infections.Our gained knowledge might have a direct impact on the society and policymakers and be directly translated into new vaccine concepts. Infektionsmedicin