慢性髓性白血病人源树突状细胞的细胞毒作用及其体外扩增(英文)

Expansion in vitro and Cytotoxicity of Dendritic Cells from Patients with Chronic Myeloid Leukemia

本研究观察来源于慢性髓性白血病患者的CD34+细胞经两步培养扩增后产生的树突状细胞的抗白血病 免疫功能。从慢性髓性白血病患者骨髓或外周血中分离出CD34+细胞或外周血单个核细胞分别进行两步培养。 首先将其与rhFlt3-L和rhTPO共育7天,再与rhGM-CSF、rhTNF-α及rhIL-4共同培养14天,以诱导树突状细胞产 生:同时以rhGM-CSF、rhTNF-α及rhIL-4直接诱导体系作对照。获得的DC通过流式细胞仪检测免疫表型,电镜分 析细胞超微结构及G显带法进行的染色体分析后,并用MTT法检测DC刺激T细胞增殖能力及T细胞对CML细 胞的杀伤作用.结果表明:慢性髓性白血病的CD34+细胞经过rhFlt3-L和rhTPO的初始扩增培养7天后,CD34+细 胞总数扩增77±5倍。用rhGM-CSF、rhTNF-α及rhIL-4诱导培养14天,DC产率达到(39±8)％,细胞扩增倍数及 DC比例均明显高于直接诱导产生的培养方法(P<0.01),且此DC能刺激自体或异体T细胞增殖,进而杀伤CML 细胞。结论:两步法体外扩增培养可明显提高DC前体总数及产率,优于直接诱导培养;CML细胞来源的DC可诱 导产生抗白血病免疫反应。

The study was aimed to investigate the extensive amplification and the cytotoxicity of dendritic cells (DC) derived from chronic myeloid leukemia cells. DC were cultured in two steps: firstly, extensive amplification in primary culture of CD34 + or mononuclear cells isolated from CML patients' bone marrow and peripheral blood with rhFlt3-L and rhTPO for 7 days; secondly, inducing culture of DC with rhGM-CSF, rhTNF and rhIL-4 for 14 days. A system inducing DC directly were established for comparison. DC were identified by immunophenotype with flow cytometry, chromosome analysis by displaying G banding and electric microscopy analysis. The function of stimulating T cells proliferation and cytotoxicity of CML cells were confirmed through MTT assay. The results showed that after first extensive amplification in primary culture with rhFlt3-L and rhTPO for 7 days, CD34+ cells had a total cell number with (77 ±5) fold expansion, and DC were(39 ±8)% of total cell respectively after induction culture of DC with rhGM-CSF, rhTNF and rhIL-4 for 14 days. Both the amplification of cell number and yield of DC were higher than the system without extensively culture ( P <0. 01). Such DC could stimulate T cells to proliferate and kill leukemia cells finally. In conclusion, two-step culture method can obviously improve the cell number of DC required, that is better than inducing them directly. DC derived from CML cells induce the generation of anti-leukemia immunization.