STI571对慢性髓细胞白血病树突状细胞发育的影响

Effects of STI571 on the development of dendritic cells derived from bone marrow mononuclear cells in patients with chronic myeloid leukemia

目的研究STI571对慢性髓细胞白血病(CML)树突状细胞(DC)发育的影响。方法分离CML患者及正常人的骨髓单个核细胞,将实验分为CML实验组、CML对照组及正常对照组。CML对照组及正常对照组:在培养体系中加入重组人粒单核细胞集落刺激因子(rhGM-CSF)和重组人白细胞介素4(rhIL-4)培养;CML实验组:在对照组的基础上,再加入药物STI571培养。于实验第8天,各组加入重组人肿瘤坏死因子α(rhTNF-α)进一步刺激成熟。Wright染色观察细胞形态,流式细胞仪检测细胞表型,荧光原位杂交(FISH)进行细胞遗传学分析,混合淋巴细胞反应(MLR)检测抗原递呈功能;ELISA法检测培养上清中血管内皮生长因子(VEGF)的浓度。结果各组均呈现典型的树突状细胞形态;CML实验组CD80、CD86、CD83和HLA-DR的表达均显著高于CML对照组(P<0．05),经FISH证实,CML DC来源于白血病细胞;各组DC均具有刺激同种异体T淋巴细胞增殖的能力,CML实验组刺激淋巴细胞增殖的能力显著高于CML对照组(P<0．05),而与正常对照组相似(P>0．05); CML实验组VEGF的浓度较CML对照组显著降低(P<0．D5)。结论STI571可促进CML骨髓来源DC的活化,可能与其抑制了CML细胞VEGF的过度分泌,从而解除了VEGF对CML DC的分化抑制有关。

Objective To investigate the effects of STI571 on the development of dendritic cells （DC） derived from bone marrow mononuclear cells of patients with chronic myeloid leukemia（CML）. Methods Bone marrow mononuclear cells （BMMNC） from CML patients and healthy volunteers were cultured initially using multiple cytokine combinations as follows： recombinant human granulocyte/ macrophage colony-stimulating-factor （rhGM-CSF） plus recombinant human interleukin-4 （rhlL-4） as CML and normal control groups, rhGM-CSF plus rhlL-4 and STI571 as CML experimental groups, and from day 8 recombinant human tumor necrosis factor-α （rhTNF-α） was added to stimulate DC maturation. The morphologic features of cells were observed by Wright＇s staining and phenotypes were assessed by flow cytometry. Cytogenetic analysis was performed by fluorescence in-situ hybridization （FISH）, and the antigen-presenting function was assayed by mixed lymphocyte reaction （MLR）. The concentration of VEGF was detected by ELISA. Results CML experimental groups treated with STI571 displayed morphological features similar to those of control groups with delicate membrane projections. However, in comparison with the CML control groups, the CML experimental groups showed an increased expression of CD80, CD86, CD83 and HLA-DR and showed more intense abilities of allogeneic antigen presentation, which were similar to those of normal control groups. FISH confirmed that DCs of both CML groups were of leukemic origin. The concentration of VEGF was dramatically reduced in CML experimental groups. Conclusion In vitro, STI571 promotes the activation/maturation of DCs derived from BMMNCs of patients with CML and decreases VEGF production by the leukemic cells. The promotion of DC maturation may be partially due to decreased inhibitory effect of VEGF.