[In-vitro and in-vivo studies on the antitumor activity of LICC in Km mice]

In order to investigate a more efficient effector cell than the classical LAK cell in tumor immunotherapy, anti-tumor activity of lymphokine-induced cytotoxic cell (LICC) was studied. The results showed that LICC had greater cytotoxicity to YAC-1, HL60, P815 and H22 tumor cells in vitro than the control spleen cells. In vivo, LICC revealed a prominent inhibiting effect on the growth of H22 cells. A mixture of LICC and H22 in the ratio of 100: 1 was injected subcutaneously into the subaxillary tissue of Km mice (Group 1). Tumor developed in 8% of the experimental animals within 10 weeks, while all of the control animals inoculated with H22 cells died from tumor in the same period (P < 0.001). In the other groups, H22 cells were injected as in group 1, but the LICC cells were administered through the tail vein (Group 2) or to the abdominal cavity (Group 3) once every week. In group 2, tumor developed in 25% of the experimental mice and 100% of the control mice (P < 0.001). In group 3, there was no significant difference in the frequency of tumor development between the experimental and control animals.