ACTA1 and Hepatic fibrosis: Liver fibrosis and intrahepatic bile duct reaction, measured by Sirius red staining, Western blots of α–smooth muscle actin (α-SMA) and collagen 1, and cytokeratin 19 (CK19) immunostaining, were significantly increased by BDL to a greater extent in KO mice than WT mice (Supplemental Figure 3, A–C).