Biologic activity of immature dendritic cells modified by FasL and TGF-β1 gene

Abstract

Objective To investigate the biological activities of immature dendritic cells (imDCs)modified by hFasL and hTGF-β1 gene,from bone marrow stem cells of rats.Methods The experiment was divided into six groups:mDC group,imDC group,empty vector group,hFasL gene modification group (FasL group),hTGF-β1 gene modification group (TGF group) and hFasL-hTGF-β1 co-transfection group (namely F-T group).The plasmids of pIRES2-EGFP-hFasL or(and) pIRES2-EGFP-hTGF-β1 were transfected into imDCs which were cultivated for six days.The expression of hFasL and hTGF-β1 gene was detected by using fluorescence microscopy,ELISA,Western blotting,flow cytometry and MLR after imDCs were transfected for 24-48 h.Results After transfection,green fluorescence was observed in the transfected imDCs under the fluorescence microscopy.ELISA revealed that the expression of hTGF-β1 in F-T group and TGF group was significantly higher than that in other groups (P ＜0.01 ) ; the expression of hTGF-β1 in imDC group,empty vector group and FasL group was significantly higher than that in mDC group (P ＜0.05) ; and the hFasL gene expression among groups had no significant difference ( P ＞ 0.05 ).Western blotting showed the positive expression of hFasL and hTGF-β1 protein in hFasL and hTGF-β1 gene modification groups.After the plasmids of pIRES2-EGFP-hFasL or(and) pIRES2-EGFP-hTGF-β1 were transfected into imDCs,CD86 and CD80 expression on the imDCs surface were lower than in mDC group by flow cytometry.The result of MLR demonstrated that the imDCs induced lower T-cells in F-T group than in TGF group (P ＜ 0.05 ) and FasL group ( P ＜ 0.05 ).Conclusion The ability of imDCs with hFasL and hTGF-β1 co-transfection was stronger than that transfected by single hFasL or hTGF-β1 in inducing allogeneic immunology tolerance. Key words: Dendritic cells; FasL; TGF-β1 ; Gene modification; Liver transplantation