Objective: To explore the effect of acellular normal and fibrotic lung matrices on alpha smooth muscle actin (α-SMA) expression in human lung adenocarcinoma cell line A549. Methods: Twenty adult SD rats were randomly divided into normal group and idiopathic pulmonary fibrosis(IPF)group (n=10 each). The pulmonary fibrosis was induced by Bleomycin. Normal and fibrotic decellularized lungs were made, then sections with 500 μm thick were cut by a standard Vibratome. None scaffold was set as control group. A549 cells were seeded dropwise into different slices (normal and fibrotic scaffolds), and cultured for one week in vitro. The expression of α-SMA was measured by immunofluorescence staining and quantitative real time polymerase chain reaction (qRT-PCR). Results: In control group, the expression of α-SMA protein was positive in A549 cells by immunofluorescence staining. However, it expressed weakly both in normal and fibrotic scaffold group, and the fluorescence intensity in fibrotic scaffold group was significant lower than that in normal group (P<0.05). The relative expression amount of α-SMA mRNA in normal and fibrotic scaffold group were (0.70±0.11) and (0.55±0.12), which were significant lower than that of control group (1.28±0.21) (P<0.05). Moreover, the relative expression of α-SMA mRNA in fibrotic scaffold group was decreased compared to that in normal scaffold group (P<0.05). Conclusions: Acellular normal and fibrotic lung scaffold can downregulate the expression of α-SMA in human lung adenocarcinoma cell line A549. It may inhibit the movement of A549 cells in acellular normal and fibrotic lung matrices, especially in acellular fibrotic lung scaffold.
目的： 观察正常及纤维化肺去细胞支架对人肺腺癌A549细胞α平滑肌肌动蛋白(α－SMA)表达的影响。 方法： 成年SD大鼠20只，按随机数字表法分为正常对照组与肺纤维化组各10只，肺纤维化组予博来霉素诱导建模，分别制备厚度为500 μm的正常去细胞与纤维化肺去细胞支架。根据A549细胞植入的支架不同分成正常支架组和纤维化支架组，单独培养的无支架A549细胞设为无支架对照组，各组分别体外培养1周，免疫荧光染色检测各组A549细胞α－SMA蛋白表达，实时荧光定量－PCR检测细胞α－SMA mRNA表达。 结果： 无支架对照组A549细胞α－SMA免疫荧光染色呈阳性表达，正常支架组与肺纤维化支架组免疫荧光染色呈弱阳性表达，其中肺纤维化支架组α－SMA免疫荧光强度显著低于正常支架组(P<0.05)；正常支架组、肺纤维化支架组α－SMA mRNA相对表达量均显著低于无支架对照组(0.70±0.11、0.55±0.12比1.28±0.21)，且肺纤维化支架组显著低于正常支架组(均P<0.05)。 结论： 正常及纤维化肺去细胞支架在体外可不同程度下调A549细胞α－SMA表达，其中纤维化肺去细胞支架作用尤为明显。.
Keywords: Cytoskeleton; Decellularization; Lung neoplasms; Pulmonary fibrosis; α-smooth muscle actin.