Representative images of senescence associated marker (β-galactosidase) and cell cycle markers (p16^INK4a, p21^cip1 and p53).

<p>SA-βgal expression (turquoise blue) in fresh liver sections of the recipients with end stage liver disease. <b>(A–B)</b> Intense SA-βgal in canals of Hering (cH), interlobular bile ducts (bd) and cholangioles (ch) in a patient with biliary atresia. (case 2) Magnification: 20×, 60×. <b>(C)</b> Ductular transformation of hepatocytes (dt) exhibiting SA-βgal in a patient with fulminant hepatic failure (case 4). Magnification: 40×. <b>(D–I)</b> Nuclear staining in formalin fixed paraffin embedded livers with end stage liver disease. <b>(D)</b> p53 canals of Hering (cH) and interlobular bile ducts (bd) in a patient with biliary atresia (case 3). <b>(E)</b> Canals of Hering (cH), interlobular bile ducts (bd) and hepatocyte ductular transformation (dt) in a patient with acute liver failure (case 4). <b>(F)</b> Hepatocytes in the regenerative nodules (h) and in the bile duct in the fibrotic bands (bd) in a patient with tyrosinemia (case 1), Magnification: 40×. <b>(G)</b> p16^INK4a staining in the hepatocytes (h) inside a regenerative nodule (case 1). Magnification: 20×, <b>(H)</b> p21^cip1, staining in bile duct (bd) in the fibrotic bands and in the hepatocytes (h) inside a regenerative nodule (case 1). Magnification: 40×. <b>(I)</b> p21^cip1 staining in the nuclei of cells that aggregate to form ductular transformation structures (dt) (case 4). Magnification 40×.