周期性机械牵张对人肺泡上皮细胞穿透素-3表达的影响

目的探讨人肺泡上皮细胞穿透素-3(PTX3)在呼吸机相关性肺损伤中的可能作用。方法应用FX4000T细胞应变加载系统,对体外培养的人肺泡上皮细胞A549周期性施加20%应变,频率为0.3Hz,加载时间为1、2、4、6h,然后采用实时定量RT-PCR检测肺泡上皮细胞PTX3表达的变化、Western blot检测分泌到培养液上清PTX3蛋白,同时检测细胞活性。结果(1)周期性牵张诱导肺泡上皮细胞表达PTX3;(2)牵张引起肺泡上皮细胞的凋亡;(3)PTX3的水平与肺泡上皮细胞的凋亡水平显著相关。结论本研究提示PTX3在呼吸机相关性肺损伤的发病机制中可能起重要的作用。

In vitro pentraxin-3 expression in human alveolar epithelial cells induced cyclic stretch

Objective To study the effect of mechanical stretch on pentraxin-3 (PTX3) expression and release in human alveolar epithelial cells(A549). Methods The cells grown on collagen 1 BioFlex plates were exposed to square cyclic stretch at 0.3Hz using the Flexercell system with 20% elongation of cells. After stretching for 1,2,4,6 hours, conditioned media were collected and the levels of PTX3 protein were measured by Western blotting. Real-time PCR of PTX3 mRNA extracted from stretched cells was performed. Apoptosis? and viability of the cells following treatments were routinely monitored. Results The results of this study showed that: 1) cyclic stretch led to increase gene expression and release of PTX3 from alveolar epithelial cells ;2 ) stretch induced apoptosis? in alveolar epithelial cells; 3) PTX3 levels correlated with severity of apoptosis of alveolar epithelial cells.C onclusion The above results suggest that PTX3 may act as an important mediator for tissue damage and play an important role for ventilator-induced lung injury