Liu Fang-jun, Deng Chun, Guo Chun-bao, Fu Zhou
Chongqing International Science and Technology Cooperation, Childrens Hospital, Chongqing, China.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi. 2012 May;28(5):474-7.
To investigate the effect of hyperoxia and TGF-β1 on epithelial-mesenchymal transition (EMT)of type II alveolar epithelial cells (AEC-II) of mice.
AEC-II cells (MLE-12 lines) were randomly divided into following groups: air exposure group, hyperoxia exposure group, air exposure combined with TGF-β1 treatment group, hyperoxia exposure combined with TGF-β1 treatment group. The morphological changes of cells in each group were observed at 6, 12, 24, 48 hours. The protein and mRNA expressions of AECII specific marker lung surfactant protein B(SP-B)and fibroblast specific marker fibroblast specific protein (FSP1)were detected by double-labeled immunofluorescence and real time-PCR at the same time point, respectively.
Along with the time of exposure to hyperoxia and TGF-β1, AECIIcells gradually changed from pebble-like shape to spindle shape, and showed some fibroblast appearances. Synchronously, the protein expression of SP-B in AECII cells decreased, whereas the expression of FSP1 increased. The co-expressed were observed at 24 hours. Comparing with that of the air exposure group, the mRNA expression of SP-B in the hyperoxia exposure group, air exposure combined with TGF-β1 treatment group, hyperoxia exposure combined with TGF-β1 treatment group decreased significantly, whereas the mRNA expression of FSP1 increased significantly at 24 hours and 48 hours (P<0.01).
Hyperoxia and TGF-β1 can induce EMT of type II alveolar epithelial cells in a time-dependent manner.
探讨高氧及转化生长因子-β1（TGF-β1）对小鼠Ⅱ型肺泡上皮细胞（AEC-II）上皮-间质转化（EMT）的影响。
将AEC-II细胞（MLE-12细胞系）随机分为以下几组：空气暴露组、高氧暴露组、空气暴露联合TGF-β1处理组、高氧暴露联合TGF-β1处理组。分别在6、12、24、48小时观察各组细胞的形态变化。同时在同一时间点通过双标免疫荧光和实时定量PCR检测AECII特异性标志物肺表面活性蛋白B（SP-B）和成纤维细胞特异性标志物成纤维细胞特异性蛋白（FSP1）的蛋白及mRNA表达。
随着高氧及TGF-β1暴露时间的延长，AECII细胞逐渐由鹅卵石样形态转变为纺锤形，并呈现出一些成纤维细胞的外观。同时，AECII细胞中SP-B的蛋白表达下降，而FSP1的表达增加。在24小时时观察到两者共表达。与空气暴露组相比，高氧暴露组、空气暴露联合TGF-β1处理组、高氧暴露联合TGF-β1处理组中SP-B的mRNA表达在24小时和48小时时显著下降，而FSP1的mRNA表达在24小时和48小时时显著增加（P<0.01）。
高氧和TGF-β1可呈时间依赖性诱导Ⅱ型肺泡上皮细胞发生EMT。
