For WB analysis, the protein concentrations of the samples were equalized and the proteins were separated by electrophoresis using an 8% polyacrylamide gel with 0.1% sodium dodecyl sulfate according to the Laemmli method. Protein transfer, control of the quality and uniformity of transfer, blocking with 5% nonfat milk, blotting with primary rabbit antibodies against rat ceruloplasmin (Cp) that cross-reacted with murine Cp, and visualization of the immune complexes were performed as described previously.6 (link) Hybond enhanced chemiluminescence (ECL) nitrocellulose membrane, ECL reagent, ECL hyperfilm (GE Healthcare, Piscataway, NJ, USA), and horseradish peroxidase-conjugated goat anti-rabbit secondary antibodies (Abcam, Cambridge, UK) were used. The film was processed using the method reported by Aldridge et al.7 (link) Protein markers with molecular masses ranging from 14.4 to 116 kDa were purchased from Thermo Scientific (Swedesboro, NJ, USA).