SERPINE2 and persistent truncus arteriosus: Then the protein expressions of serpinE2 were detected by ELISA assay and the results showed that serpinE2 protein expression was significantly increased ~2.35 fold in plasma of TAC mice compared with control mice (Fig. 1d), which was consistent well with the notion of ELISA and western blot showing ~1.29 fold (Fig. 1d) and ~1.23 fold (Fig. 1e) increases in myocardium of TAC mice.