Abstract
Regenerative activity was studied in the liver surface using a monoclonal antibody against DNA polymerase alpha in 25 patients of various liver diseases. In acute viral hepatitis with confluent necrosis, active regenerative foci were found adjacent to small depressed lesion. In chronic active hepatitis, active regenerative foci were predominantly found in periportal zone surrownding the reddish markings. In cirrhotic nudules, the number of hepatocytes stained with DNA polymerase alpha was various. Accordingly, active regenerative foci were not found.