[Induction of anti-hepatocellular carcinoma immunity by Hyper-IL-6 gene in vivo].

AIM: To prepare the mouse hepatocellular carcinoma (HCC) cells with the stable expression of Hyper-IL-6 and explore the possibility of inducing active anti-HCC immune response by Hyper-IL-6 gene. METHODS: Hyper-IL-6 gene was transfected into mouse HCC cells MM45T.Li using Lipofectamine(TM);2000. G418-resistant clones named MM45T-HIL-6 were selected and detected for the expression of Hyper-IL-6 gene by RT-PCR and ELISA. Mouse HCC cells transfected with pEGFP-C1, named MM45T-mock, were prepared as controls. Tumor models were established by injecting subcutaneously 5×10(5); cells of MM45T.Li, MM45T- mock and MM45T-HIL-6 on the right anterior limb of BALB/c mouse, respectively. In vivo experiments were performed to observe the tumorigenicity of MM45T.Li, MM45T-mock and MM45T-HIL-6. The levels of CD4(+); and CD8(+); T cells in mouse peripheral blood were detected by flow cytometry (FCM). RESULTS: RT-PCR and ELISA showed that Hyper-IL-6 gene was expressed in the MM45T-HIL-6 cells, but not in the control cells. We observed that the tumorigenicity of MM45T-HIL-6 decreased compared with control cells after they were inoculated subcutaneously into mice. FCM results indicated that the levels of CD4(+); and CD8(+); T cells in the peripheral blood significantly increased in the mice inoculated with MM45T-HIL-6 compared with the ones inoculated with MM45T.Li and MM45T-mock cells (P<0.05). CONCLUSION: The mouse HCC cells with the stable expression of Hyper-IL-6 can induce active anti-HCC immune response after inoculated subcutaneously into mice.