[Activation of anti-tumor cytotoxic T lymphocytes by fusion of human dendritic cells and melanoma cells].

Objective To determine the effect of activation of specific anti-tumor cytotoxic T lymphocytes (CTL) and the ability of cross-presentation in vitro by fusion of HLA-A2+ human dendritic cells (DCs) with HLA-A2-melanoma cells. Methods The HLA-A2+ human dendritic cells and HLA-A2-melanoma cells were fused by PEG and were cultivated in complete RPMI1640 media containing FCS (10%) and GM-CSF for 24~48 h,and then co-cultured fusion cells with Melan-A specific T cells. HLA-A2-melanoma cells were negative control,While T2 cells and DC+Pts were positive control. The activation of anti-tumor CTL elicited by the fusion cells was detected by intracellular cytokine staining. Results The immature DC could express CD80,CD83,CD86,HLA-DR,and HLA-ABC,but the mature DC induced by TNF-α,PGE-2,and CD40L further highly expressed above molecules. The rate of specific CTL cells primed by the fusion cells was 16.72%±4.26%,negative control was 0.21%±1.84%,and positive control was 28.60%±5.67%. The CTL from vaccine by fusing DC and LAR6 induced lysis of HLA-A2+ LAR1 cells. Conclusion The HLA-A2 restricted specific anti-tumor CTL can be induced in vitro by fusion of HLA-A2+ human dendritic cells with HLA-A2-melanoma cells.