Abstract: | To analyze the antitumor potential and mechanism of action of simultaneous Newcastle disease virus (NDV) hemagglutinin-neuraminidase(HN) and human interleukin 18(hIL-18) gene transfer in C57BL/6 mice with H22 hepatoma,the mouse model with H22 hepatoma was established in C57BL/6 mice, and the antitumor effects of the combined application of NDV HN and hIL-18 were evaluated in vivo. The results show that the growth of established tumors in mice immunized with adenovirus(Ad)-HN in conjunction with Ad-hIL-18 was significantly inhibited compared with that in mice immunized with Ad-HN, Ad-hIL-18 alone, or the empty vector(Ad-mock). Furthermore, the immunization of mice with Ad-HN in conjunction with Ad-hIL-18 elicited strong natural killer activity and H22 tumor-specific cytotoxic T lymphocyte(CTL) responses in vivo. In addition, T cells from the lymph nodes of mice immunized with Ad-hIL-18 or Ad-HN+Ad-hIL-18 secreted high levels of the Th1 cytokine IL-2 and interferon-γ (IFN-γ), indicating that the regression of tumor cells is related to a Th1-type dominant immune response. These results demonstrate that vaccination with NDV HN together with hIL-18 may be a novel and powerful strategy for cancer immunotherapy. |