TUNEL-positive hepatocytes in alcoholic liver disease. A retrospective biopsy study using DNA nick end-labelling

Alcohol-induced damage to the liver results in a wide array of typical alterations. Whereas the mechanisms involved in the pathogenesis of fatty change, hepatocyte ballooning, Mallory body formation and fibrosis have been studied in detail, little is known about hepatocyte apoptosis in alcoholic liver disease (ALD). In this retrospective study we analysed parenchymal cell death in ALD systematically by the use of in situ DNA nickend labelling (ISEL/TUNEL). We show that increased hepatocyte TdT labelling occurs in ALD. Labelling is observed more frequently in parenchymal areas exhibiting advanced damage (ballooning degeneration with or without Mallory bodies, cholestasis and perisinusoidal fibrosis). In addition, hepatocyte TdT labelling is higher where there is septal fibrosis and nodular remodelling. Conversely, it is not elevated in ballooning hepatocytes themselves, but rather in the apparently normal hepatocytes in their vicinity.