骨髓增生异常综合征中CD34^+细胞CXCR4的表达及其与细胞迁移的相关性

CXCR4 expression of bone marrow CD34^+ cells in myelodysplastic syndromes and its correlation with cell migration

目的:探讨不同危险度骨髓增生异常综合征(myelodysplasticsymdromes,MDS)中骨髓CD34+细胞CXCR4的表达情况及其与细胞迁移率的相关性。方法:收集40例骨髓增生异常综合征患者的骨髓标本,根据IPSS积分系统进行危险度分组。低危组20例:IPSS积分0~1.5分;高危组20例:IPSS积分≥1.5分;同时采集10例健康者的骨髓标本作为对照。分离纯化骨髓CD34+细胞,通过流式细胞术检测CXCR4膜蛋白的表达;研究SDF-1α趋化作用下CD34+细胞的迁移率及CD34+细胞对骨髓基质细胞的迁移率。结果:高危组MDS患者CD34+细胞CXCR4的表达率明显高于低危组和正常对照组(P<0.000 1);低危组和正常对照组之间CXCR4的表达率无显著性差异(P>0.05)。高危组CD34+细胞对SDF-1α及骨髓基质细胞的迁移率显著高于低危组及正常组(均P<0.000 1),且其对骨髓基质细胞的迁移率与CXCR4的表达呈正相关(P=0.000 1)。结论:高危组MDS患者CD34+细胞CXCR4的表达量及其对骨髓基质细胞的迁移率均明显高于低危组患者,且其迁移率随CXCR4表达量的增加而升高,不同风险组的MDS患者存在SDF-1及其受体CXCR4表达和功能上的差异,SDF-1及其受体CXCR4在MDS发病中具有重要作用。

Objective： To evaluate the expression of CXCR4 and the migration rate of bone marrow stromal CD34 cells in different risk groups with myelodysplastic syndromes （MDS） using correlation analysis. Methods： Forty MDS patients were divided into low- and high-risk groups based on the International Prognosis Scoring System （IPSS）. The former was composed of 20 patients with IPSS〈1.5, whereas the latter was composed of 20 patients with IPSS 〉 1.5. Bone marrow （BM） samples of these patients and 10 normal controls were collected. CD34 cells were separated and purified. The expression of CXCR4 was determined by flow cytometry. The migration rate of CD34 cells on the chemotactic effect of SDF-1 and on the effect of bone marrow stromal cells were measured. Results： The expression rate of CXCR4 was higher in the high-risk MDS group than in the low-risk and control groups （P〈0.000 1）. No significant differences existed between the low-risk and the control groups （〉0.05）. The migration rate of CD34＋ cells on the ef fects of SDF-1 a and marrow stromal cells were significantly increased in the high-risk MDS group compared with those in the low-risk and control groups （P〈0.000 1）. Migration rate of CD34 cells on the effect of marrow stromal cells was positively correlated with CX- CR4 expression （P=0.000 1）. Conclusion： The CXCR4 expression and migration rates of CD34＋ cells on the effect of marrow stromal cells are significantly higher in the high-risk MDS group than in the low-risk group. Migration rate has a positive correlation with the CXCR4 expression, which further indicates that MDS is a heterogeneous group of hematopoietic stem cell malignancies. The expres- sion and function of SDF-1 and its receptor CXCR4 differ within each group with various risks. SDF-1 and CXCR4 may be involved inMDS pathogenesis.