The value of isolated hepatocyte transplantation as a temporary support in acute hepatic failure remains controversial regarding the functional capacities of freshly isolated and transplanted hepatocytes. To evaluate the survival rate of intrasplenically transplanted liver cells and their response to a proliferation stimulus like partial hepatectomy, 3H-thymidine incorporation into hepatic and auxiliary transplanted hepatocyte DNA was determined. The survival rate of intrasplenically transplanted hepatocytes was evaluated by analyses of m-albumin-RNA within the splenic tissue and compared to the morphological findings. The histological results show a marked decrease (greater than x 100) of intrasplenically transplanted hepatocytes within 1 week after injection. The amount of surviving cells then remained constant for 3 months without any signs of proliferation. After partial hepatectomy a stimulation of hepatic regeneration was observed in the remaining liver tissue but not in auxiliary transplanted hepatocytes. M-albumin-RNA determination of auxiliary transplanted hepatocytes revealed a decrease of m-albumin-RNA concentration of greater than 100 times within 24 h after transplantation indicating early cell necrosis of the transplanted cells. Since intrasplenically transplanted hepatocytes underwent an early cell necrosis without any evidence for a directly postoperatively inducible cell proliferation, it is concluded that a sufficient metabolic support in acute hepatic failure cannot be taken into consideration.