中文摘要：

目的：观察镁对分离培养的健康人和哮喘患者外周血CD4＋CD25＋调节性T细胞凋亡及叉头框蛋白3（Foxp3）表达的影响.方法：经磁珠分离法分离出健康人和哮喘患者外周血CD4＋CD25＋T细胞,分镁剂干预组（10 mmol/L）及空白组培养72 h后,用流式细胞仪检测CD4＋CD25＋T细胞的凋亡率及Foxp3表达情况.结果：（1）健康人外周血CD4＋CD25＋T细胞的纯度为77.4%～92.3%,哮喘患者CD4＋CD25＋T细胞的纯度为75.2%～93.8%.（2）CD4＋CD25＋T细胞占外周血CD4＋T细胞的比例在健康组为4.12%～7.98%,在哮喘组为4.51%～8.68%,两者没有显著差异（P＞0.05）.（3）镁（10 mmol/L）可以诱导健康组及哮喘组外周血CD4＋CD25＋T细胞凋亡率增加（P＜0.05）,但对Foxp3的表达无影响（P＞0.05）.结论：镁促进CD4＋CD25＋T调节细胞凋亡增加可能为其治疗支气管哮喘的作用机制之一.

英文摘要：

AIM：To observe the apoptosis and the expression of forkhead box protein 3（Foxp3） induced by magnesium in CD4＋CD25＋ regulatory T cells isolated from healthy and asthmatic human peripheral blood. METHODS：Peripheral blood from healthy volunteers and asthma patients was collected. CD4＋CD25＋ T cells were separated by Percoll centrifugation and magnetic separation. The cells were cultured for 72 h and treated with magnesium（10 mmol/L） or control solution. The apoptotic rate and the expression of Foxp3 in the cells were analyzed by flow cytometry. RESULTS：The purity of CD4＋CD25＋T cells was 77.4%~92.3% in health group, and was 75.2%~93.8%in asthma group. The proportion of CD4＋CD25＋ T cells in CD4＋T cells was 4.12%~7.98% in healthy adults, and 4.51%~8.68% in asthma patients. No significant difference between the 2 groups was observed. Magnesium at concentration of 10 mmol/L up-regulated the apoptotic rate of CD4＋CD25＋ T cells（P〈0.05） and did not affect the Foxp3 expression in the cells in both health and asthma groups. CONCLUSION：Magnesium plays therapeutic effects on asthma by inducing the apoptosis of peripheral CD4＋CD25＋ regulatory T cells.