PROS1 and blood coagulation disease: The observed decrease of PROS1 anticoagulant protein in SARS-CoV-2 positive biopsies strengthens the association between coagulopathies development and SARS-CoV-2 in situ presence, possibly through PROS1 impairment by proteolytic activity, carried out by SARS-CoV-2 PLpro viral protease [40] (Figure 4).