长期血液透析患者内皮祖细胞变化与同型半胱氨酸的关系

Changes of endothelial progenitor cells and the correlation with the hyperhomocysteinemia in chronic renal failure patients subject to long-term hemodialysis.

目的检测长期血液透析患者内皮祖细胞（EPCs）数量和功能的改变，并探讨其与同型半胱氨酸的关系。方法采用密度梯度离心法分离培养长期血液透析患者和健康者的外周血单个核细胞，将其接种在人纤维连接蛋白包被培养板，7d后取贴壁细胞进行Dil—LDL和FITC—UEA-I双染色，并通过流式细胞仪检测其表面标志CD34、CD133、KDR，以鉴定EPCs。采用改良的Boyden小室、粘附功能检测评价其迁移和粘附能力，并与患者血清半胱氨酸含量进行相关性分析。结果患者EPCs的数量和迁移、粘附功能都低于健康者，差异有统计学意义（P〈0．05）；患者血清半胱氨酸含量[（57．10±24．76）umol／L]显著高于健康者[（6．75±3．58）umol／L]（P〈0．05），并且含量与患者EPCs的数量和迁移、粘附功能分别呈明显负相关（P〈0．05）。结论长期血液透析患者的EPCs数量减少，功能降低，可能与患者的高同型半胱氨酸血症有关。

Objective To investigate the change of endothelial progenitor cells （EPCs） in pa tients subject to long term hemodialysis and the correlation with the hyperhomocysteinemia. Methods Total mononuclear ceils were isolated from peripheral blood of patients subject to long-term hemodial ysis and a normal control group by Ficoll density gradient centrit＇ugation and then were plated on human fibronectin-coated dishes. After culture for 7 days, EPCs were characterized as adherent cells by double staining FITC-UEA-I binding and Dil LDL, and were further documented by demonstrating the expression of CD34, CD133 and KDR by using flow cytometry. EPCs migration was determined by modified Boyden chamber assay. EPCs adhesive assay was performed by replanting EPCs on humanfibronectin-coated plates and then counting the adherent cells. The relationship between the number and activity of EPCs and hyperhomocysteinemia was also assessed. Results Number of EPCs and migratory and adhesive capacity were significantly reduced （P〈0. 05）, and serum homocysteine level was significantly increased in patients with high Hcy as compared with control subjects [ （57. 10 ± 24. 76） umol/L vs （6. 75 ± 3.58）umol/L, P〈0. 05]. The serum homocysteine level of the patients with high Hcy were significantly correlated with a reduction of EPCs level and activity （P〈0. 05）. Conclusions The number and activity of EPCs were decreased in patients subject to long term hemodialysis, and these were probably correlated with hyperhomocysteinemia of patients.