The T cell response to SARS-CoV-2: kinetic and quantitative aspects and the case for their protective role
Abstract SARS-CoV-2, the etiological agent of COVID-19, triggers an adaptive immunity in the infected host that results in the production of virus-specific antibodies and T cells. While kinetic and quantitative aspects of antibodies have been analyzed in large patient cohorts, similar information about SARS-CoV-2-specific T cells are scarce. We summarize in this review the available knowledge of quantitative and temporal features of the SARS-CoV-2 T cell response. Currently, most of the data derived only from the analysis of the circulatory compartment. Despite this limitation, early appearance, multi-specificity and functionality of SARS-CoV-2-specific T cells are associated with accelerated viral clearance and with protection from severe COVID-19.