Which cells are critically contributing to CSS in severe COVID-19?
CSS encompasses the activation of large numbers of blood cells, including B cells, natural killer cells, macrophages, dendritic cells, neutrophils, monocytes, resident tissue cells and epithelial and endothelial cells. Their activation cause a massive release of pro-inflammatory cytokines, which drives pathology.68The cells involved in CSS during COVID-19 have not been fully determined yet. In SARS-CoV and MERS-CoV infection, airway epithelial cells, dendritic cells and macrophages were the most important cell types releasing a large amount of proinflammatory cytokines.49,69