PM2.5长期暴露诱导对人支气管上皮细胞上皮-间质转化行为的影响
陆润泽,崔 健,张程程,李晓波*

(东南大学公共卫生学院,江苏 南京 210009)

PM2.5; 支气管上皮细胞; 上皮-间质转化

Influence of long-term PM2.5 exposure induced epithelial-mesenchymal transition of human bronchial epithelial cells
LU Runze,CUI Jian,ZHANG Chengcheng,LI Xiaobo*

(School of Public Health,Southeast University,Nanjing 210009,China)

PM2.5; bronchial epithelial cells; epithelial-mesenchymal transition

DOI: 10.6043/j.issn.0438-0479.201807033

备注

为探讨PM2.5诱导人支气管上皮(HBE)细胞发生的慢性损害作用,用0,100,500 μg/mL的PM2.5分别处理HBE细胞多代后,经细胞计数试剂盒(CCK-8)法检测发现暴露组的细胞活性较对照组显著增强.进而选择细胞活性差异最大的一组观察PM2.5长期暴露对HBE细胞形态、功能和上皮-间质转化标志物分子水平的影响,结果显示:暴露组细胞发生形态变化,周期较对照组表现为G1期阻滞,但凋亡率未出现明显改变; 与对照组相比,暴露组细胞的克隆数目和迁移能力存在浓度依赖性的增加; 暴露组细胞中上皮标志物的表达水平下调,而间质标志物的表达水平上调.此外,将长期暴露的HBE细胞(P35)经裸鼠尾静脉注射入体内21 d后,高剂量暴露注射组的小鼠肺组织出现肺泡炎症,但未观察到肿瘤细胞定植.采用动物全身动态暴露系统对小鼠进行21 d的PM2.5吸入染毒后,应用微计算机断层扫描(Micro-CT)和苏木精-伊红(HE)组织染色技术观察到小鼠肺部出现PM2.5颗粒沉积和炎症改变,且部分肺组织中存在纤维增生与黏液栓阻塞.综上可知,PM2.5暴露可诱导正常HBE细胞发生功能改变,使其具备一定的上皮-间质转化特征.

To investigate the chronic damage induced by PM2.5 in human bronchial epithelial(HBE)cells,HBE cells were treated with PM2.5 of 0,100 and 500 μg/mL respectively for several passages,followed by the CCK-8 assay.The results showed that the cell activity of the exposure group was significantly higher than that of the control group.The group with the greatest difference in cell activity was selected to observe the effects of long-term exposure to PM2.5 on cellular morphology,function and molecular levels of epithelial-mesenchymal transition markers in HBE cells.The results showed that the morphological changes were observed in the exposed cells.The cell cycle was blocked by G1 phase compared with the control group,but the apoptosis rate did not change significantly.Compared with the control group,the number of cell clones and migration ability of the exposed group increased in a concentration-dependent manner,the expression of epithelial markers was down-regulated,and the expression of interstitial markers was up-regulated in the exposed cells.In addition,long-term exposed HBE cells(P35)were injected through the tail vein into the body of nude mice.After 21 d tail vein injection,alveolar inflammation emerged in the lung of high-dosage injected mice, but no signs of tumor formation were found in the lung of nude mice.After the mice were subjected to dynamic inhalation of PM2.5 for 21 d with the systemic dynamic exposure system,particulate matter deposition,inflammatory infiltration and fibrosis in the lungs were observed using Micro-CT and tissue hematoxylin-eosin staining technologies.In conclusion,PM2.5 exposure can induce functional changes in normal HBE cells and make them possess certain epithelial-mesenchymal transition characteristics.