Studies of anti-tumor effect of human IL-12 using SCID mouse engrafted human cancer cells

We investigated the anti tumor effect of human interleukin 12 upon human cancer cells through PBMC or NK cell. In Experiment 1, we engrafted lung squamous cancer cell line, 2E9, subcutaneously and injected IL-12 intraperitoneally for 4 weeks. No effects on tumor growth were observed comparing with the controls. In Experiment 2, we injected gastric cancer cell line, MKN 45, PBMC and IL-12 intraperitoneally. A follow up injection of IL- 12 was given for 4 weeks. The tumor was completely rejected in the MKN 45+PBMC+IL-12 group. Serum levels of human immunoglobulin and IFN γ in MKN 45+PBMC+IL-12 group were significantly enhanced over PBMC group and MKN 45+PBMC group. The Western blot analysis showed that the specific human antibodies to MKN 45 were produced in the serum of mice in the MKN 45+PBMC+IL-12 group.