脐血AC133~+细胞迁移率与趋化因子受体CXCR4相关性研究

目的探讨脐血AC133+细胞迁移率与趋化因子受体CXCR4相关性。方法采用双色直接免疫荧光标记法,使用流式细胞仪测定在含干细胞因子(SCF)、Flt3配体(FL)、血小板生成素(TPO)培养条件下,在培养的第0、4、7、10、14天脐血AC133+细胞表面CXCR4表达水平,并用跨膜迁移实验(Transwell实验)来评价在相同趋化因子基质细胞衍生因子(SDF)-1浓度条件下细胞迁移率。结果重组人造血生长因子组合SCF、FL、TPO体外培养AC133+细胞时,培养的早期,SDF-1受体CXCR4的表达升高,同时迁移率也升高。但随着培养时间的延长,CXCR4表达量渐渐降低,迁移率随之降低。结论通过Transwell Plate可以有效地模拟细胞穿越内皮现象。AC133+细胞迁移率与趋化因子受体CXCR4表达量间存在相关性,应用CXCR4阻断抗体后AC133+细胞迁移率与未加SDF-1差异无统计学意义。

Correlation between the migration rate of cord blood AC133+cells and the expression of CXCR4

Objective To explore the correlation between the migration rate of cord blood AC133^＋ cells and the expression of chemokine receptor CXCR4. Methods The expressions of CXCR4 in fresh and cultured CB AC133^＋ cells （days 0, 4, 7, 10 and 14） were analyzed with two-color direct immunofluorescence flow cytometry, in the presence of SCF, Flt3 ligand and TPO. Cell migration rate with specified concentration of SDF-1 was detected in a Transwell System. Results When AC133^＋ cells were cultured in vitro with a combination of hemopoietic growth factors, the expression of CXCR4 showed an early increase, but declined over time, which was parallel with the change of migration rate of AC133^＋ cells. Conclusion Transwell Plate was shown to perfectly simulate the cell penetration of endothelium. There was a correlation between the migration rate of AC133^＋ cells and the expression of chemokine receptor CXCR4. There was no difference in the migration rate of cord blood AC133^＋ cells between the group using CXCR4-blocking antibody and the group without SDF-1.