Heparanase is a heparan sulfate degrading enzyme, which also has affinity for UFH.45Heparanase activity seems to be increased during inflammatory disease including sepsis-associated lung injury or bacterial and viral infection.46Evidence for increased heparanase expression in COVID-19 is lacking, but based on its ability to cleave UFH it could be involved in the ethology of heparin resistance in COVID-19 and may also be a potential target for further research. Here, HPSE is linked to viral infectious disease.