ABSTRACT
Objective To investigate the specific anti-tumor immune response induced by dendritic cells (DCs) transfected with total RNA of human pancreatic cancer Capan-2 cells.Methods DCs were isolated and cultured from peripheral blood mononuclear cells (PBMCs) derived from six patients with pancreatic cancer.Total RNA of Capan-2 cells and MUC4 mRNA were transfected into DCs by electroporation.The survival rate of transfected DCs was determined by MTT method and the expression of MUC4 mRNA in DCs was detected by Western blotting.The activity of cytotoxic T lymphocyte cells (CTLs) induced by DCs transfected with total RNA of Capan-2 cells were evaluated by IFN-γ ELISA and the induction of specific CTL response to the killing effect on pancreatic cancer cell in vitro were measured by 51 Cr standard cytotoxicity test.Results The survival rate of DCs transfected with total RNA of Capan-2 cells (DC-Capan-2-total RNA) showed a decrease in a time dependent manner and the survival rate was reduced to 60.81％ after transfection for 96 h.The survival rate of MUC4 mRNA transfection DCs (DC-MUC4 mRNA) was stable at around 80％.The difference of DCs surviral rate between the two groups was statistically significant (P ＜ 0.05).The amount of MUC4 protein expression of DC-Capan-2-total RNA was significantly lower than that of DC-MUC4 mRNA (P ＜0.05).The quantity of CTL IFN-γ release induced by DC-Capan-2-total RNA was (89.34 ± 3.85)U/mL and the quantity of DC-MUC4 mRNA induced CTL IFN-γ release was (21.77 ± 21.77)U/ml There was statistically significant between the two groups (P ＜0.05).In addition,the specific CTLs induced by DC-Capan-2-total RNA could effectively identify and kill the HLA-A2+/MUC4+ Capan-2 and the HLA-A2+/MUC4-PANC 1 cells,and could not effectively identify and kill the HLA-A2 /MUC4-MiaPaCa-2 cells and the HLA-A2-/MUC4 + AsPC-1 cells.Conclusions A more pronounced CTL anti-tumor immune response can be induced by DCs transfected with total RNA of Capan-2 cells compared with a single tumor associated antigen,but it is limited by MHC class Ⅰ antigen presented.