In an activated Mdr2 (an ortholog of human ABCB4 gene) mouse model for PFIC3, hydrophobic BAs toxicity induces liver injury such as in PFIC3 patients with cholangitis, ductular proliferation, periportal fibrosis, susceptibility to the formation of gallstones and HBCs occurrence. This evidence concerns the gene ABCB4 and fibrosis.