白细胞介素-1β在气道重塑中作用的实验研究

目的研究前炎症因子白细胞介素-1β(IL-1β)对气道上皮细胞(BEC)转化生长因子-β1(TGF-β1)的调控,以探讨其在气道重塑中的作用。方法选择原代分离新西兰种白兔的BEC作为研究对象,体外培养,将培养细胞随机分4组:对照组和IL-1β处理A、B、C组。A、B、C组分别加入终浓度为0·1、1、10mg/L的IL-1β作用24h,对照组加入等量无血清培养液,采用原位杂交和免疫细胞化学染色的方法观察各组TGF-β1mRNA和蛋白的表达。结果TGF-β1mRNA和蛋白表达IL-1β处理A组(0·162±0·023、0·156±0·003)、B组(0·318±0·013、0·614±0·020)、C组(0·644±0·016、0·917±0·050)均较对照组(0·098±0·020、0·138±0·009)显著增强,差异有统计学意义(P均<0·01),A、B、C组两两比较差异有统计学意义(P均<0·01),其中IL-1β处理C组TGF-β1mRNA和蛋白表达均最强,随IL-1β浓度的增加,TGF-β1mRNA和蛋白表达呈剂量依赖性增加。结论前炎症因子IL-1β可上调气道上皮细胞TGF-β1的表达,当过度调节后可导致气道重塑。

Effect of interleukin-1β on airway remodeling

Objective To evaluate the effect of interleukin-1β(IL-1β) on the expression of transforming growth factor (TGF)-β_1 in the bronchial epithelial cell and the effect of IL-1β on airway remodeling.Methods Primary bronchial epithelial cells were obtained from rabbit trachea and cultured in vitro.After cell growing up to colony,it was divided randomly into 4 groups:normal control group,IL-1β treated groups A,B and C,stimulated by IL-1β(0.1,1,10 mg/L,repectilvely)for 24 hours,and the normal control group incubated with equal serum free conditioned medium.Cell-coated dishes were attained, then the expression of TGF-β_1 was measured by in situ hybridization and immunocytochemistry.Results ①Cell morphology and identification:Bronchial epithelial cells grew in a typical epithelial fashion forming a fully confluent monolayer with cobblestone appearance and its characteristics were identified by positive immunostaining of keratin.②Effect of IL-1β on expression of TGF-β_1 mRNA:The expression of TGF-β_1 mRNA in IL-1β treated groups A(0.162±0.023),B(0.318±0.013)and C(0.644±0.016)was significantly higher than that in normal control group(0.098±0.020)(P<0.01),and there was significant difference in groups A,B and C in terms of TGF-β_1 mRNA expression (P<0.01).③Effect of IL-1β on expression of TGF-β_1 protein:The expression of TGF-β_1 protein in IL-1β treated groups A(0.156±0.003),B(0.614±0.020),and C(0.917±0.050)was significantly higher than that in normal control group(0.138±0.009)(P<0.01), and there was significant difference in groups A, B and C in terms of TGF-β_1 protein expression (P<0.01).Conclusion Pre-inflammatory cytokine IL-1β can upregulate the expression of TGF-β_1 mRNA and protein in bronchial epithelial cell.The ability of IL-1β to modulate TGF-β_1 release may contribute to both abnormal airway repair and development of airway remodeling.