Migration And Differentiation Of Primordial Germ Cells In Normal Liver Microenviroment

Objectives To investigate the migration and differentiation of primordial germ cells in normal liver microenviroment.Materials and Methods 1. Materials Mouse primordial germ cells isolated from fetal urogenital ridges at 11 day DMEM/F12 and fetal bovine serum(Gibicol) Ribbit anti rat Albumin polyclone antibody(Abcam) Mouse anti Brd U monoclone antibody(Abcam) 5-bromo-2-deoxyuridine(Brd U)(Sigma,America) 2. Methods After primordial germ cells(PGCs) were cultured and proliferated in vitro, these cells were labelled with 5-bromo-2-deoxyuridine(Brd U) and transplanted by tail vein injection into the isogeneic normal mouse. The liver tissue was extracted from those mice with transplantation for 2, 4, 6 and 8 weeks and normal control mice. The 10?m cryostat liver continuous sections were prepared. The migration and differentiation of the Brd U positive transplanted cells were detected by immunohistochemistry, double immunoflorescence for Brd U and hepatic-specific marker ALB. The change of hepatic glycogen and microstructure of the mice with transplantation were analyzed by PAS and hematoxylin and eosin(HE) staining respectively.Results The ratio of Brd U positive cells labelled with Brd U in vitro was above 90%. The Brd U positive transplanted cells were found in the normal liver tissue of all mice with PGCs transplantation for 2, 4weeks. Some cells with large round nucleus were showed Brd U and ALB double positive, however, some cells with small or irragular nucleus were in single Brd U positive immunoreaction. At this time the Brd U and ALB double positive cells were with the PAS strong positive reaction. But the number of Brd U positive cells and the PAS reaction in those liver tissue with PGCs transplantation for 4 weeks were lower and less than that for 2 weeks. But the number of hepatic cells in the liver with PGCs transplantation for 4 weeks was higher than that for 2 weeks, but lower than that in normal liver tissue. Morever, the volume and its nucleus of those hepatic-like cells in the mice with PGCs transplantation were large and loose chromatin compared with the normal hepatocytes. After 6 and 8 weeks of transplantation the number of Brd U positive cells and the Brd U staining intensity was decreased, and the volume of liver cells and morphology of nuclei tended to be normal. Brd U positive hepatocytes were negative in the liver tissue of 4 mice and small mass of Brd U positive cells was observed in the liver tissue of 1 mouse with transplantation for 8 weeks.Conclusion PGCs by vein transplantation could migrate into the isogeneic normal liver tissue and differentiate into hepatocytes in the normal hepatic microenvironment. At 8 weeks after transplantation the liver microstructure was to restore normal...