实验性矽肺大鼠中IP-10和TARC的表达及意义

Changes and significance of IP-10 and TARC in lungs of experimental silicotic rat

目的研究Th1相关趋化性细胞因子IP-10(IFN-γ-inducible protein,干扰素诱导蛋白10)和Th2相关趋化性细胞因子TARC(thymus and activation regulated chemokine,胸腺和活化调节趋化因子)在实验性矽肺大鼠染尘后不同时间点的表达水平及意义。方法将54只雄性SD大鼠随机分为模型组和对照组各27只。模型组采用非暴露式气管内一次性注入1 ml生理盐水二氧化硅悬液建立大鼠矽肺模型,对照组气管内注入1 ml灭菌生理盐水。分别在染尘后第1、7、14、21、28、35、77、106、126天处死两组大鼠各3只,结扎右肺,对左肺进行肺泡灌洗,收集其肺泡灌洗液并用ELISA法检测IP-10和TARC含量;免疫组化S-P法分析右肺组织中IP-10和TARC的表达情况。结果成功构建大鼠矽肺模型;模型组肺泡灌洗液中IP-10在第1、7、14、21天明显增多,与对照组相比差异有统计学意义(P<0.05);TARC在第1、7、14、21、28、35天明显增多,与对照组相比差异有统计学意义(P<0.05)。肺组织免疫组化结果用图像分析系统进行半定量分析,与对照组相比,染尘后第1、7、14、21天,模型组大鼠矽肺组织中IP-10表达差异有统计学意义(P<0.05);染尘后第1、7、14、21、28、35天,模型组大鼠矽肺组织中TARC表达差异有统计学意义(P<0.05)。结论 Th1和Th2相关趋化性细胞因子募集Th1及Th2细胞到肺组织中参与大鼠矽肺病变的免疫调节过程。

Objective To investigate changes and their significance of Th1/Th2 related chemokines in lungs of rat silicosis models at dif- ferent developmental stages. Methods Fifty-four male SD rats were randomly divided into the silica exposure group and the control group. One ml silica suspension （40 g · L^-1） was administrated via intratraeheal instillation once while equal amount of saline was in- stilled to the rats of control group. Animals were sacrificed at the 1st ,7th ,14th ,21st ,28th ,35th ,77th ,106th ,and 126th day after the instilla- tion. After ligation of the fight lung,the left lung was lavaged and Bronchoalveolar Lavage Fluid （BALF） collected. The contents of IP-10 and TARC in BALF were assayed by enzyme linked immunosorbent assay （ELISA） ;the expressions of IP-10 and TRAC in lungs were observed by immunohistochemistry method. Results The rat silicosis model was constructed successfully. In early stage of the experi- ment （1st ,7th, 14th ,21st day） ,levels of IP-10 in the lungs of silicotie rats obviously increased than those in control group （P 〈 0.05 ）, and in later stage of the experiment the levels of IP-IO had no obvious difference with control group （ P 〉 0.05 ）. The levels of TARC in lungs of silicotie rats were higher than those in control group in early stage （1 st ,7th, 14th ,21 st, 28t h, 35th day） （P 〈 0.05 ） and in later stage of experiment the levels had no obvious difference with control group （ P 〉 0. 05 ）. Conclusion Th1/Th2 related chemokines play roles in the immune regulation process in rats with silicosis.