Regenerating liver cells

The morphogenesis of hepatocytes after massive hepatic necrosis to recovery through liver cell regeneration has not been fully understood. Sequential biopsies were performed on the native liver of a 22-year old man who underw ent auxiliary partial orthotopic liver transplantation 1 month after fulmin ant hepatitis. Auxiliary partial orthotopic liver transplantation was succe ssful, and the biopsy samples permitted us to examine the regenerating proc ess of hepatocytes after massive necrosis. At the time of auxiliary partial orthotopic liver transplantation (postoperative day 0), 95% of hepatocytes were lost and a few ductules were found in the portal areas. The ductules stained with cytokeratin 19. At postoperative day 7, the ductules began to increase in size and number and became dilated over a period of 1 month, wh en individual hepatocytes with clear cytoplasm appeared from ductules. As t he differentiation of hepatocytes increased the expression of cytokeratin 1 9 was found to decrease. From 2 to 3 months, all of the ductules were trans formed into hepatocytes, and they began to form round clusters. From 3 to 6 months, the round cell clusters became organized into trabecula with fibro sis. From 6 to 12 months, a lobular architecture was established, and by 14 months, the necrotic liver was fully recovered to normal. This study by ex amination of sequential biopsies demonstrates the progression of the regene rating profess from total hepatic necrosis to complete recovery.