Mechanism of development and progression of chronic lung injury --- An approach from mechanical property of cultured lung fibroblasts -

我们研究了由肺成纤维细胞组成的细胞片在包被纤维连接蛋白的硅胶膜上的压力-体积曲线。在培养皿底部打一个大洞，在培养皿外面粘贴一层厚度为20微米的硅胶膜。培养皿底部涂有小牛纤维连接蛋白。将人胚胎肺成纤维细胞粘附在RBMI-1640培养基（细胞片）中涂有纤维连接蛋白的硅酮膜上。通过注射和抽吸介质使细胞片膨胀和收缩，并保持一个圆顶。检测了穹顶的体积变化和穹顶内的压力。得到的压力和体积值绘制在X-Y坐标上。硅胶膜本身在本研究中施加的应力范围内在同一轨迹上膨胀和收缩。纤维连接蛋白包覆硅氧烷膜和细胞片的压力-体积曲线呈现迟滞回线。显微镜检查显示，在压力-体积偏移前后，细胞没有脱离薄片。含有edta的胰蛋白酶处理分离成纤维细胞后，细胞片的迟滞环似乎比胰蛋白酶处理前的细胞片变小。我们的结论是，肺成纤维细胞的力学特性可以用这种方法来测量。

We studied the pressure-volume curve of a cell-sheet consisted of lung fibroblasts cultured on fibronectin-coated silicone membrane. A large hole was made in the bottom of a culture dish and a silicone membrane(20micron in thickness)was pasted up on the outside of the dish. The bottom of the dish was coated with calf fibronectin. Human embryo lung fibroblasts were allowed to adhere to the fibronectin-coated silicone membrane in RBMI-1640 medium(cell-sheet). Cell-sheet was inflated and deflated with keeping a dome by injecting and withdrawing medium. Volume change of the dome and the pressure inside the dome were detected-. Obtained pressure and volume values were plotted on a X-Y coordinate. Silicone membrane itself expanded and contracted on the same locus within the stress applied in this study. Pressure-volume curve of fibronectin-coated silicone membrane and cell-sheet showed hysteresis loop. microscopical check showed no detachment of the cells from the sheet before and after pressure-volume excursion. The hysteresis loop of cell-sheet from which fibroblasts were detached by EDTA-containing trypsin treatment seemed to become smaller than that of cell-sheet before trypsin treatment. We conclude that mechanical property of lung fibroblasts may be able to be measured in this way.