SERPINE1 and severe acute respiratory syndrome: Also called PAI1 or PLANH1, SERPINE1 (serpin family E member 1) encodes a member of the serine proteinase inhibitor (serpin) superfamily, which is the suppressor of tissue plasminogen activator (tPA) and urokinase (uPA), and it is also capable of inhibiting the fibrinolysis process.[46] During the epidemic of SARS, Wu et al have already found that the SERPINE1 level raised.[47] A similar elevation reappeared in COVID-19 patients during the pandemic.