TGFB2 and primary biliary cholangitis: Northern blot analysis has revealed enhanced expression of TGF-β1, TGF-β2, TGF-β3, and their receptors in human liver cirrhosis [129]; TGF-β2 has been identified as an actively transcribed TGF-β gene during the progression of liver fibrosis in biliary atresia [130]; statistically significant changes in serum TGF-β1 levels have been demonstrated in common bile duct-ligated rats and in PBC patients [131–133]; an overexpression of TGF-β3 has been observed in hepatocytes in PBC patients [134].