Effect of a vaccine prepared by fusion of HepG2 cells with dendritic cells from patients with hepatocellular carcinoma in vitro

    ZHANG Hongª²Mei, ZHANG Liª²Wang£¬ LIU Wenª²Chao£¬PAN Boª²Rong, SI Xiaoª²Ming, REN Jun

    Center of Clinical Oncology, Xijing Hospital, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To investigate the fusion ability of hepatocellular carcinoma (HCC) patientª²derived dendritic cells (DCs) with HCC cells (HepG2) in inducing autologous T lymphocytes to elicit specific immunity against HCC in vitro. METHODS: Peripheral blood mononuclear cells (PBMCs) from HCC patients were isolated by blood separator. In the presence of recombinant human granulocyte/macrophageª²clone stimulating factor (rhGMª²CSF) and interleukinª²4 (rhILª²4), PBMCs were cultured in vitro for 1 week to induce DCs. The expression of cell surface molecules was assessed by flow cytometry. The fusion cells of DCs with HepG2 cells (DCs/HepG2) were achieved by polyethylene glycol (PEG). The ability of DCs/HepG2 to stimulate the proliferation of autologous T lymphocytes was evaluated by MTT assay and the specific lysis of HepG2 by DCs/HepG2 induced cytotoxic T lymphocytes (CTLs) was detected by cytotoxicity test. RESULTS: After fusion, DCs/HepG2 highly expressed surface molecules, including CD83 90.4%, CD80 87.7%, CD86 84.4% and HLAª²DR 98.5%. The fusion cells had a remarkably greater ability to stimulate the proliferation of autologous T lymphocytes in comparison with HepG2 and DCs. The DCs/HepG2ª²activated CTLs showed a potent specific lysis to HepG2 cells, which was (63.5¡À4.6)% with an effectorª²target ratio 20¡Ã1. CONCLUSION: The fusion of DCs derived from HCC patients with HepG2 cells can effectively stimulate autologous T lymphocytes to elicit specific antitumor immunity against HCC and may serve as a promising vaccine for immunotherapy of HCC. ......