Objective To develop a method for injecting immune cells that target the liver and suppress tumor growth there. Method A hollow fiber pad was placed into the liver subcapsule of nu-mice bearing SW480 tumors， leading to cyst formation in the subcapsule. Dendritic cells（DCs） and cytokine-induced killer cells（CIKs） were induced from human peripheral blood monocytes. The ability of CIKs to inhibit SW480 cell proliferation was measured. DCs were loaded with antigens from SW480 cells， and co-cultured with CIKs. DC-CIK co-cultures were injected into the subcapsule cyst or into the caudal vein（6×107 cells in 0.3 mL）， while the same volume of saline was injected into the cyst or caudal vein in control groups. Each group received injections twice a week for 4 weeks. At 48 h after the last injection， growth inhibition of the primary tumors in spleen and mean numbers of metastic tumors in liver were determined. Results Mixing CIKs and SW480 cells in the ratio of 60：1 inhibited SW480 proliferation by （75.3±8.42）%. CD3/CD56 were expressed on（36.4±13.2）% of CIK cells. Tumor inhibition was 32.07% in the animals injected in the cyst and 16.54% in the animals injected in the caudal vein（P<0.05）；mean numbers of metastic liver tumors were 2.47±1.02 in the group injected in the cyst and 5.05±1.06 in the group injected in the caudal vein（P<0.01）. Conclusion Injecting DC-CIKs into nu-mice may significantly inhibit the growth of primary tumors in spleen
and metastic tumors in liver， and the effects are greater when the cells are injected into the liver subcapsule than into the caudal vein.
