SARS-CoV-2-Specific T Cell Memory with Common TCRαβ Motifs Is Established in Unvaccinated Children Who Seroconvert after Infection

The authors recruited convalescent COVID-19 children and adults to define their circulating memory SARS-CoV-2-specific CD4+ and CD8+ T cells prior to vaccination. They analyzed epitope-specific T cells directly ex vivo using seven HLA class-I and class-II tetramers presenting SARS-CoV-2 epitopes, together with Spike-specific B cells.