摘要目的 探讨CXCR4阻断剂AMD3100对白血病细胞与成骨龛黏附的影响及逆转白血病细胞耐药的作用.方法 在生物衍生骨上接种白血病患者骨髓来源的间充质细胞,并诱导其分化为成骨细胞,构建一种仿生性的成骨龛,并用ELISA法检测培养上清中SDF-1的表达水平;然后在成骨龛中接种FLT3-ITD突变阳性的白血病细胞株MV4-l1细胞,构建三维共培养体系,流式细胞术检测CXCR4的表达水平;在此共培养体系中加入AMD3100后,应用BCECF荧光标记测定白血病细胞的黏附率,流式细胞术分析阿糖胞苷(Ara-C)作用前后白血病细胞凋亡的变化.结果 ①白血病骨髓成骨细胞培养7、14、21d上清中SDF-1含量分别为(304± 18)、(410±28)和(396± 16)pg/ml,第14天达高峰;MV4-11细胞CXCR4表达水平为(72±16)％.②AM D3100作用 24 h,成骨龛对MV4-11细胞黏附率为(40.1±8.1)％,而不加药物的对照组为(65.6± 12.1)％,差异有统计学意义(P＜0.05).③加入Ara-C前,AMD3100作用组细胞的凋亡率为(5.6±0.8)％,对照组为(2.5±0.5)％.加入0.02、0.20、2.00 μg/mlAra-C后,AMD3100作用组细胞凋亡率增加为(10.0±2.4)％、(17.8±2.3)％和(25.1±2.4)％,明显高于对照组[分别为(6.7±1.0)％、(10.3±1.5)％、(16.2±3.1)％](P值均＜0.05).结论 AMD3100能够阻断骨髓成骨细胞龛和白血病细胞的相互作用,在逆转白血病细胞耐药中起重要作用.

abstractsObjective To study the blocking effect of CXCR4 inhibitor AMD3100 on the adhesion of leukemia cells to osteoblast niche,and the reversal of multidrug resistance in leukemia cells.Methods Mesenchymal stem cells (MSCs) from leukemia patients were planted on the bio-derived bone scaffolds and then induced into osteoblasts to establish the bio-osteoblast niche.The levels of SDF-lwere tested with ELISA.The leukemia cell line MV4-11 cells with FLT3-ITD mutation were inoculated into the bio-osteoblast niche to build a three-dimensional co-culture system.The expression level of CXCR4,adhesion and apoptosis rates of leukemia cells were observed by flow cytometry after incubation with AMD3100 and Ara-C for 24 h and 48 h.Results ①The supernatant levels of SDF-1 in cultured osteoblast were (304±18),(410±28) and (396±16) pg/ml on 7th,14th and 21th day,respectively.It reached the highest on 14th day.The expression level of CXCR4 in cultured MV4-11 cells was (72±16)％.②Adhesion rate of MV4-11 cells to osteoblast niche was (40.1±8.1)％ after AM D3100 treatment for 24h,while that of control group was (65.6±12.1)％ (P＜0.05).③The apoptosis rate of MV4-11 cells incubated with AMD3100 for 24h was (5.6±0.8)％,while that of control group was (2.5±0.5)％.The apoptosis rates of AMD3100-induced MV4-11 cells were (10.0±2.4)％,(17.8±2.3)％ and (25.1±2.4)％ after treatment with Ara-C at 0.02,0.20,2.00mg/ml respectively and they were (6.7±1.0)％,(10.3±1.5)％,(16.2±3.1)％ respectively in AMD3100-noninduced control group,the difference was significant (P＜0.05).Conclusion AMD3100 can block the interaction between osteoblasts niches and leukemia cells,and play an important role in the reversal of multidrug resistance in leukemia cells.