Immunosuppressive Action Of FTY720 In Rat Homogeneity Hepatocellular Transplantation

Objective:To master the way of isolating and purifying hepatocyte through an in-situ collagenase cycle perfusion.To investigate the immunosuppressive effect of FTY720 on T lymphocyte subsets and the number of lymphocyte in rat allograft hepatocyte transplantation model and the immunosuppressive mechanisms.Methods:Preparation of ALF model:10%D-gal solution was prepared and injected to rates via abdominal cavity with dosage of 1.0g/kg respectively.Cell separation and purification: Collagenase perfusion was performed on SD rats to separate liver cells and suspension was counted.SD rats with ALF induced by D-gal was performed intrasplenic hepatocyte transplantation(approximately 2×10~7)and were randomly divided into two groups:GroupⅠandⅡ.GroupⅡreceived FTY720 5mg/kg.day by administration.Liver function,the splenic pathohistological,the number of lymphocyte in the recipients was performed.The T lymphocyte subsets and the IL-2Rα(CD25~+)were detected by using immunohisto-chemistry technique.Results:after 24 hours,the hepatic failure model was performed.The comparison between groupⅠand groupⅡshows that significant differences were found in ALT and TBil after FTY720 was given by administration(p＜0.05).The number of lymphocyte in peripheral blood of groupⅡis evidently lower than groupⅠ(p＜0.05).T lymphocyte subsets CD4~+,in groupⅡwas significantly decreased compared with groupⅠ,so did the CD4~+/CD8~+.At the same time,the IL-2Rα(CD25~+) was decreased significantly too.Conclusion:FTY720 raise the survival rat of hepatocellular transplantation; significantly decreased the CD4~+ T lymphocyte subsets;and the percentage of CD4~+/CD8~+ is inverted.At last,the IL-2Rα(CD25~+) was decreased significantly,depress the clone of T lymphocyte.