SELL and COVID-19: When focusing on T cell subclasses, some markers of memory were over-expressed (e.g. SELL/CD62LFigure 8, CD103/ITGAESupplementary Figure 8), while others were under-expressed or unchanged (e.g. CCR7, CD27, CD28Supplementary Figure 8) in COVID-19 compared to HLTY and INFL, without matching a specific type of memory T cell.