Abstract: OBJECTIVE: To evaluate the modified culture method and the therapeutic efficiency of immune-killer cells (IKCs) on a hepatocarcinoma cell line BEL-7402. METHODS：IKCs were induced and amplified from PBMC cells in a modified NK culture method. The immunophenotype changes were analyzed by flow cytometry. The proliferation of the cells were evaluated by Trypan-blue staining. The killing activities on BEL-7402 cell line were detected by Alamar Blue staining and their effect on BEL-7402 tumor in the nude mice model were examined by monitoring tumor growth. RESULTS：The IKCs cultured for 14 days multiplied approximately 300 times. Cell subsets of CD3+CD56+，CD3-CD56+ and CD8+ were the major components. Both ratios of CD3+CD56+ and CD3-CD56+ were higher than 85%，while the ratio of CD8+ was higher than 77%. At the effector-target ratio of 25：1 and 100：1，the killing activity against BEL-7402 cells of IKCs was 66.5% (P＜0.01) and 97.8% (P＜0.01)，respectively. Treatment with IKCs on BEL-7402 tumor in nude mice showed a noticeable higher therapeutic effect than that of control，with an inhibition ratio on tumor growth of 69% (P＜0.01). CONCLUSION：The modified culture method for IKCs was practicable and effective. The research might provide experimental basis for clinical immunotherapy of IKCs on hepatocarcinoma.

Key words: immune-killer cells, hepatocarcinoma, killing activity