Fig. (3) Secretion of prolegumain in serum from DJ-1-knockout mice.Secretion levels of legumain in serum from DJ-1-knockout mice were examined by Western blotting (A). The relative secretion level of prolegumain is shown (B). The relative secretion level of prolegumain was also examined by ELISA (C). Statistical analyses were carried out using Student’s t-test. Significance: **p<0.01, ***p<0.001.