The Study Of Myeloid Leukemic Cells Induced To Differentiate Into Dendritic Cells

OBJECTIVE: To induce and differentiate into dendritic cells from leukemic cells of patients with myeloid leukemia. MATERIAL AND METHODS: Nonadherent cells from bone marrow or peripheral blood mononuclear cells of 20 patients with myeloid leukemia and adherent cells from 8 healthy volunteers were cultured with rhGM-CSF and rhIL-4. The cytokines were supplemented every three days. RhTNF-αwas used at the ninth day. All the cells were harvested at the twelfth day. The morphology of cells were detected by using microscope, invert microscope and electron microscope, while the phenotypes were analyzed by using flow cytometry. The proliferation of T cells was performed by methyl thiazolyl tetrazolium (MTT) assay. RESULT: After culture, cells from 17 samples and all the 8 healthy volunteers' samples exhibited typical morphogical features of DCs. Through flow cytometry , we found the expression of HLA-DR of 17 leukemic samples was increased from 23.66±20.02% to 46.85±24.07%, CD86 was increased from 5.13±5.04% to 15.69±13.96%, CD1a was increased from 13.82±13.22% to 28.35±19.74%. There were significantly statistical difference among them(P<0.01), but there were no statistical difference compared to that of healthy volunteers(P>0.05). These leukemic-DCs had more powerful capacity than that of control in mixed leukocyte responses. CONCLUSION: Myeloid leukemic cells can differentiate into dendritic like cells which exhibited DC's morphology, phenotypes and functions.