Induction of specific anti-tumor immune responses against pancreatic cancer by transfected dendritic cells with pancreatic cancer MUC1 mRNA

Abstract

Objective To investigate the induction of specific anti-tumor immune response by transfected dendritic cells (DCs) with MUC1 mRNA of human pancreatic cancer,and to provide the experimental evidences for the treatment of human pancreatic cancer with DC vaccine.Methods DCs were isolated and cultured from peripheral blood mononuclear cells (PBMCs),and then were identified by cell morphology and surface markers.After being transcripted and amplified,MUC1 mRNA was transfected into DCs by electroporation.The expression of MUC1 in DCs at different time points was detected by quantitative real-time PCR and Western blot.The survival rate of DCs before and after tramrfection was determined by MTT method.The induction of specific cytotoxic T lymphocyte (CTL) response by MUC1 mRNA transfected DCs was measured by 51Cr standard cytotoxicity test.The released amount of IFN-γ was evaluated by ELISA method.Results The cultured cells appeared typical characteristics with regard to morphology and phenotype (CD40 +,HLA-DR+,CD83 +,CD86 + ).After MUC1 mRNA transfection for 48 h,the expression of MUC1 mRNA of DCs reached the highest point ( 38.43 ) and the MUC1 protein expression also reached the highest point at 72 h.The survival rate of DCs was stabilized around 80％ after transfection.The DCs transfected with MUC1 mRNA could effectively induce HLA-A2+/MUC1 + specific CTL immune responses.Stimulated by pancreatic cancer cell line Capan-2 cells or the DCs transfected with MUC1 mRNA,the IFN-γ released in 24 h by MUC1 specific CTL were ( 28.44 ± 4.96 ) U/m1 and ( 16.31 ± 2.54) U/ml,respectively.The difference between the two groups was statistically significant (P ＜0.05 ).Conclusions DCs transfected with human pancreatic cancer MUC1 mRNA could induce CTLs and produce specific anti-tumor immunity. Key words: Dendritic cells; RNA,messenger; Transfection; Pancreatic neoplasms; T-lymphocytes,cytotoxic