Abstract: Abstract Objective: To investigate the killing effects of stem cell-derived Dendritic Cells (DC) co-cultured with cytokine induced killer (CIK) on Leukemia Stem Cells（LSC）from the same source. Methods: Bone marrow mononuclear cells were isolated from CML-AP donors, CD34+CD38-CD44+ cells were sorted by flow cytometry, cultured and induced to DC. The mononuclear cells from the same doner were induced to CIK. DC and CIK were co-cultured to determined killing effects. The expressions of DC's and CIK's markers typical、P-gp resistance protein were detected by flow cytometry. The expressions of bcr/abl fusion gene of leukemia stem cells and DC were detected by fluorescence in situ hybridization (FISH). The cytotoxicity activity was measured by lactate dehydrogenase release assay. Results: DC and CIK showed typical immunophenotype. DC expressed P-gp resistance protein, and DC's bcr/abl fusion gene was positive. The killing effect increased with effector-target ratio. It was showed that under an effector-target ratio of 40:1 the killing effect was highest. At this level, killing rate can reach to (59.13±12.82)%. Conclusion: Leukemia stem cell-derived DC's functions were normal, and killing effects can be found when they were co-cultured with CIK.

Key words: dendritic cells, chronic myelogenous leukemia, Leukemia Stem Cells, cytokine induced killer, P-glycoprotein