DNA synthesis in hepatocytes during liver allograft rejection in rats

We have investigated DNA synthesis in hepatocytes after orthotopic liver transplantation in four rat combinations--DA into DA (isogeneic), DA into PVG (allogeneic, nonrejector), DA into BN (allogeneic, rejector), and DA into (BN X PVG)F1 (allogeneic, intermediate nonrejector). The methods used were assay of thymidine kinase activity in graft homogenate and staining of hepatocytes in liver sections by an antibromodeoxyuridine monoclonal antibody. Both demonstrated increased DNA synthesis in grafts in all combinations except isogeneic, and showed that its intensity and timing paralleled the occurrence of the rejection reaction. The significance of hepatocyte regeneration after liver grafting is discussed.