Considering that neutrophils are the most abundant leukocytes in humans [33], that blood leukocytes infiltrate tissues by transmigrating through the vascular endothelium, and that S-proteins can be shed and are present in bodily fluids, microvessels, and tissues of SARS-CoV-2 infected patients [7,17], we investigated the effect of S-proteins and endothelial–neutrophils interactions on the adhesion molecule P-selectin, markers of endothelial injury and increased coagulopathy (vWF), NETosis (cit-H3) and inflammation (IL-6). This evidence concerns the gene PROS1 and blood coagulation disease.