ST段抬高型急性心肌梗死患者外周血中树突状细胞及其亚型的变化

The Alteration of Circulating Dendritic Cells and Subtypes in ST-Elevated Acute Myocardial Infarction

目的:探讨ST段抬高型急型心肌梗死(acute myocardial infarction,AMI)患者外周血中树突状细胞(dendritic cells,DCs)及其亚型的变化。方法:选择17例ST段抬高型AMI患者(AMI组)和14例稳定型心绞痛(stable angina pectoris,SAP)患者(SAP组)为研究对象,并以15例性别、年龄相匹配的冠状动脉造影阴性者为对照组。采用流式细胞技术三色分析法测定3组人群外周血中DCs及其亚型占外周血单个核细胞的百分比和绝对数,其中DCs以Lin1-HLA-DR+确定,髓样树突细胞(myeloid dendritic cell,mDC)以Lin1-HLA-DR+CD11c+确定,浆细胞样树突状细胞(plasmacytoid dendritic cell,pDC)以Lin1-HLA-DR+CD123+确定;并采用酶联免疫吸附试验法检测3组人群外周血中白细胞介素6(interleukin-6,IL-6)和肿瘤坏死因子(tumor necrosis factor-α,TNF-α)水平。其中ST段抬高型AMI患者在AMI发作7 d后进行随访。结果:AMI组患者急性期(<24 h)DCs占外周血单个核细胞的百分比、DCs的绝对数、mDC和pDC占外周血单个核细胞的百分比、mDC和pDC的绝对数、mDC与pDC比值均低于SAP组和对照组(P<0.01、0.05)。发作7 d后复查,AMI组DCs占外周血单个核细胞的百分比、DCs的绝对数、mDC和pDC占外周血单个核细胞的百分比、mDC和pDC的绝对数、mDC与pDC比值均高于急性期(P<0.01、0.05)。SAP组与对照组外周血中DCs占外周血单个核细胞的百分比、DCs的绝对数、mDC和pDC占外周血单个核细胞的百分比、mDC和pDC的绝对数、mDC与pDC比值差异均无统计学意义(P>0.05)。AMI患者急性期血清TNF-α及IL-6水平高于对照组和SAP组(P<0.05),发作7 d后IL-6水平明显降低(P<0.05)。结论:AMI时外周血中的DCs包括mDC及pDC在急性期均明显降低,发作7 d后恢复至正常水平,提示外周血中DCs在AMI急性期可能参与了不稳定斑块的形成。

Objective：To analyze the frequency and alteration of circulating dendritic cells（DCs）and subtypes in patients with ST-elevated acute myocardial infarction（AMI）.Methods：A total of 17 patients with ST-elevated AMI（AMI group）and 14 patients with stable angina pectoris（SAP）as SAP group and 15 people with normal coronary angiogram with matched age and gender（control group）were enrolled.The absolute number and percentage in peripheral blood mononuclear cells of circulating DCs,myeloid dendritic cell（mDC）and plasmacytoid dendritic cell（pDC）in the three groups were detected using the 3-colure staining flow cytometry.The levels of interleukin-6（IL-6）and tumor necrosis factor-α（TNF-α）were detected with enzymelinked immunosorbent assay.In the AMI group,these indexes were measured on the 7th day after the attack.Results：The percentage of circulating DCs in peripheral blood mononuclear cells and the absolute number of DCs,the percentage of circulating mDC and pDC in peripheral blood mononuclear cells and the absolute numbers of mDC and pDC and mDC/pDC ratio in the AMI group on the day of attack（24 h）were significantly lower than those in the control group and the SAP group（P〈0.01 or0.05）.In the AMI group,on the 7th day after the attack,the percentages of DCs,mDC and pDC in peripheral blood mononuclear cells and the absolute numbers of DCs,mDC and pDC and mDC/pDC ratio were higher than those on the day of attack（P〈0.01 or 0.05）.The level of IL-6 and TNF-αin the AMI group on the day of attack were significantly higher than those in the control group and SAP group（P〈0.05）,and the level of IL-6 decreased on the 7th day after the attack in the AMI group（P〈0.05）.But there was no significant difference in the percentage of DCs,mDC and pDC in peripheral blood mononuclear cells and the absolute numbers and mDC/pDC ratio between the control group and the SAP group（P〈0.05）.Conclusions：Circulating mDC and pDC are significantly reduced in patients on the day of attack of AMI,and it can increase to nearly normal on the 7th day after attack.It indicates that the possibility of DCs recruits into coronary plaques and improve the formation of unstable plaque.