肿瘤坏死因子-α单克隆抗体干预矽肺纤维化的实验研究

Interventive effect of TNF-α monoclonal antibody on silica-induced pulmonary fibrosis in rats

目的观察肿瘤坏死因子-α(TNF-α)单克隆抗体(英夫利西)对矽尘诱导的大鼠肺纤维化的抑制作用,探讨英夫利西治疗肺纤维化的可能机制。方法将48只雄性Wistar大鼠随机分为3组,每组16只。染尘组和干预组大鼠气管内一次性注入50 mg SiO_2粉尘,次日起干预组给予15 mg/kg英夫利西皮下注射,共5 d,染尘组仅注射等量生理盐水;对照组气管内和皮下均注射生理盐水。各组分别于建模后7 d、14 d处死大鼠各8只,以HE、Masson染色对肺组织炎症和纤维化程度进行评价。ELISA法检测血、支气管肺泡灌洗液(BALF)中TNF-α含量,Western blot检测肺组织NF-κB蛋白表达量。结果英夫利西干预后,肺泡炎评分(7 d)和纤维化评分(14 d)优化;血清TNF-α含量降低,BALF中TNF-α含量仅7 d降低,7 d时NF-κB p65蛋白表达下调,以上结果差异均具有统计学意义(P<0.05)。结论TNF-α单克隆抗体可降低TNF-α水平,进而抑制NF-κB信号通路的活化,缓解矽尘诱导的大鼠肺纤维化进程。

Objective To observe the inhibiting effect of TNF-α monoclonal antibody （infliximab） on silica-induced pulmonary fibrosis in rats, to explore the possible mechanism of infliximab in silicosis treatment. Methods Forty-eight Wistar rats were randomly divided into treatment group （n= 16） , model group （n= 16） and control group （n= 16）. 50 mg SiO2 dusts were injected into trachea of the rats of silica-exposed group and intervention group, from the second day of silica-exposure the rats of intervention group received 15 mg/kg by s. c injection of infliximab for 5 days, the rats of silica-exposed group were injec- ted with N. S; while the control rats only administrated with N. S both trachea and subcutaneous injection. 7 and 14 days after silica exposure, 8 rats of each group were killed, respectively, the lung tissue were stained with H＆E and Masson＇s trichromedye for observing inflammation and fibrosis, TNF-α levels in serum and bronchoalveolar ]avage fluid （BALF） were measured with en- zyme linked immunosorbent assay （ELISA）, NF-KB p65 expression was measured quantitatively by Western blot method. Results The results showed that after intervention of infliximab, the severity of pulmonary inflammation and fibrosis all were improved, the levels of serum TNF-α （7 d, 14 d） and BALF TNF-α （7 d） were decreased, and the rising of NF-KB p65 protein expression （7 d） was also inhibited （P〈0. 05） . Conclusion The resuhs suggested that TNF-α monoclonal antibody can reduce TNF-α level, inhibit NF-KB signal pathway and alleviate the progress of pulmonary fibrosis by silica in rats.