卫生研究

目的检测Th1/Th2型细胞因子在实验性矽肺大鼠肺组织中的动态表达水平。方法将SPF级成年雄性SD大鼠随机分为染尘组和对照组,每组42只。模型组采用非气管暴露法一次性注入1 m L二氧化硅悬液(100 mg/m L)建立大鼠矽肺模型,对照组气管内注入等量灭菌生理盐水。分别在染尘第1天、1周、2周、3周、6周、9周和12周各处死6只大鼠,采用酶联免疫吸附实验(ELISA)检测大鼠肺组织匀浆中肿瘤坏死因子-α(TNF-α)、干扰素-γ(IFN-γ)、白介素18(IL-18)、白介素4(IL-4)、白细胞介素10(IL-10)及IFN-γ/IL-4的表达水平。结果染尘组TNF-α表达量均高于对照组(P<0.05);染尘组IFN-γ在染尘第1天²周表达量高于对照组(P<0.05);染尘组IL-18表达量均高于对照组,差异无统计学意义;染尘组IL-4在染尘第1周表达量低于对照组(P<0.05),第9周及12周高于对照组(P<0.05);染尘组IL-10在染尘第6⁹周表达量高于对照组(P<0.05);染尘组Th1/Th2比值随染尘时间增长而降低,染尘组Th1/Th2在染尘第1天²周比值高于对照组(P<0.05)。结论在矽肺的发生发展过程中细胞因子发生变化:Th1型细胞因子持续高表达,Th2型细胞因子表达量先降低后升高。

Objective To determine the role of Th1 / Th2 cytokines in lung tissue of experimental silicotic rat. Methods 84 healthy SPF male SD rats were randomly divided into silica exposure group and control group. Silica suspension at 1 m L( 100 mg / m L) was administrated once by injection of non-exposure bronchus while equal amount of saline was instilled to the rats in control group,rats were sacrificed at 1^st day,1^st,2^th,3^th,6^th,9^th and 12 ^th week after instillation. Cytokines in lung tissue were detected by ELISA. Results Compared with healthy control,the levels of TNF-α was increased at each point in silica exposure group( P < 0. 05). The IFN-γ in silica exposure group was increased in 1^st day,1^st and 2^th week( P < 0. 05). There was no significant difference about IL-18 between silica exposure group and control group. The IL-4 in silica exposure group was decreased in 1^stweek,and increased in 9thweek and 12^th week( P < 0. 05). The IL-10 in silica exposure group increased in 6^th and 9^th week( P < 0. 05). The ratio of Th1 / Th2 of silica exposure group was increased in 1^stday,1^stand 2^th week( P < 0. 05). Conclusion The expression of Th1 cytokines are kept at a high level,Th2 cytokines decrease firstly and increase subsequently. Differential expressions of cytokines play an important role in development of silicosis.