ABSTRACT
Objective:To investigate the possibility of producing vaccine with higher effect of anti-hepatoma by means of freezing the tumour cells which have been modified by TNF-? genes before. Methods: H22 cells which had been modified by TNF-? genes were treated by means of freezing and 60Co radiation or of 60Co radiation, respectively. Then, they were put to use to produce two kinds of vaccines. Effects of these two kinds of vaccines on anti- plant-hepatoma in mice were compared. Results: Effects of increasing the inhibiting rates, the levels of lectin-induced IL-2 and TNF from splenocytes, and the splentic NK activity, were all obviously seen stronger in vaccine made up of cells treated by the method combined with freezing, than that in vaccine made up of cells by no freezing. Conclusion: Method of freezing, after procedure of TNF-a gene modifying, could raise up the immunogenicity of the tumour cells, thereby enhance the anti-plant-hepatoma effect in mice induced by the vaccine.
ABSTRACT
Objective To investigate the killing activity of tumor infiltrating lymphocytes (TIL) stimulated by dendritic cells (DC) on gastric carcinoma cells in vitro. Since DC is the strongest antigen presenting cell (APC) which has been known, it can present antigens to T lymphocytes, including TIL, and can induce cytotoxic T lymphocyte (CTL) responded in vivo and vitro. Methods DC were isolated from the peripheral blood of patients with gastric carcinoma and stimulated by granulocyte/macrophage colony stimulating factor (GM CSF), interleukin 4 (IL 4) and tumor antigen. Then TIL were stimulated by DC and their killing activity on autogenous gastric carcinoma cells and SGC 7901 cells in vitro were observed. Results TIL stimulated by DC had very high killing activity on autogenous gastric carcinoma cells and the killing rate was (89.39?3.05)%, which was much higher than those of TIL not stimulated by DC and T lymphocytes stimulated by DC as well as T lymphocytes not stimulated by DC on autogenous gastric carcinoma cells. The killing rates of the last three ones were (54.37?1.50)%, (53.92?1.46)% and (3.55? 0.25) % respectively. However, their killing activity on SGC 7901 cells was lower. Conclusions The results indicate that DC from patients with gastric carcinoma can induce efficient and specific anti gastric carcinoma immune responses.