Expansion of dendritic cells derived from patients with chronic myeloid leukemia in vitro

AIM: To investigate the expansion and the function of dendritic cells derived from chronic myeloid leukemia cells. METHODS: DC was cultured in two steps: first CD34 + or mononuclear cells isolated from CML patients' bone marrow and peripheral blood with rhFlt3 L and rhTPO was cultured for 7 days and then they were coincubated with rhGM CSF, rhTNF and rhIL 4 to induce DCs for 14 days. A directly DCs induced system was established for comparison. DCs were identified by immunophenotype, chromsome and electric microscopy analysis. The function of stimulating T cells proliferation and cytotoxicity of CML cells was confirmed by MTT assay. RESULTS: After the two step culture, CD34 + cells had a total cell number with (76.56±5.17) fold expansion and the yield of (39.10± 8.03 )% DCs respectively for 21 days, both of which were higher than those by the system without expansion culture ( P 0.01). This DCs stimulated T cells to?proliferate and finally killed the leukemia cells. CONCLUSION: Two step culture can obviously improve the cell number and the production of DCs, better than directly inducing method. DCs derived from CML cells can induce the generation of anti leukemia immunization.