SDC1 and COVID-19: Endotheliopathy is marked by an increased level of plasma von Willebrand factor (VWF), E-selectin, plasminogen activator inhibitor-1 (PAI-1), soluble thrombomodulin (sTM), and syndecan-1 [8], which is strongly associated with a poor outcome in patients with severe COVID-19 [9,10].