人B7-2瘤苗与DC瘤苗体外联合诱导抗食管癌的作用

Combination effect of human B7-2 and dentric cells vaccines in anti-esophageal cancer in vitro

AIM: To investigate the roles of human B7-2 combined with dentric cell (DC) vaccine in inducing anti-tumor immunity against esophageal cancer in vitro. METHODS: Human esophageal cancer cell line EC9706 was transfected with the vector of pEGFP-N3-B7-2 by lipofectamine method. The mononuclear cells (MNCs) were separated from cord blood by density gradient centrifuga-tion (Ficall-Hypaque) and then were induced to differentiate by cell factors. On the 3rd day, EC9706 cytolysis antigen was added into the medium, in which DCs gradually matured and expressed special tumor antigen. After the matured DCs were co-cultured with autologous T cells derived from cord blood for 3 days, the T cells were activated to become tumor specific cytotoxic T lymphocytes (CTL). The inhibition of CTL on the transfected and untransfected EC9706 cells was detected by methyl thiazolyl tetrazolium (MTT) assay. RESULTS: The EGFP-B7-2 fusion gene was expressed mainly on the membrane of EC9706 cells, which proved the transfection was successful. Mature DCs with tumor cytolysis antigene was able to activate naive T cells to become tumor specialized CTL, and the CTL had significant inhibitory effect or killing response on EC9706 cells transfected with pEGFP-N3-B7-2(F= 21.672,P= 0.000). CONCLUSION: The human B7-2 combined with DC vaccine can induce significant killing response on esophageal cancer cell.