[Effect of two different acellular lung matrices on α-SMA expression in A549 cells]

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.