度普利尤单抗对特应性皮炎模型小鼠TLR3表达的影响

Effect of Dupilumab on the Expression of TLR3 in Atopic Dermatitis Model Mice

目的 探讨皮下注射度普利尤单抗对特应性皮炎(AD)模型小鼠Toll样受体3(Toll-like recepter 3,TLR3)表达的影响。方法 将32只BALB/c小鼠(6周龄,24 g左右)随机分为对照(NC)组、AD组、度普利尤单抗10mg/kg组、25mg/kg组,每组8只。NC组小鼠两侧耳部应用无水乙醇涂抹,其余各组小鼠两侧耳部涂抹2 nmol/L卡泊三醇(MC903)擦剂,1次/d,重复14 d。2周造模结束后,度普利尤单抗组分别给予10 mg/kg和25mg/kg的度普利尤单抗皮下注射,2次/周。AD组、NC组则给以等体积生理盐水腹腔注射,4组小鼠均干预1周,再过1周后处死小鼠并采集组织。采用HE染色观察皮损病理学形态特征,甲苯胺蓝染色观察皮损肥大细胞数量,免疫组织化学及Western blot实验检测皮损中IL-4、IL-13Rα1、TLR3的蛋白表达情况。结果 AD组小鼠出现典型的特应性皮炎样皮损及相应的组织病理学改变,度普利尤单抗组观察到小鼠皮损较AD组红斑明显减轻,表皮增生程度减轻,炎症细胞浸润减轻等。与NC组相比,AD组的小鼠皮损组织中的IL-4、IL-13Rα1、TLR3高表达,度普利尤单抗组小鼠皮损组织中的IL-4、IL-13Rα1、TLR3较AD组表达则降低。结论 皮下注射度普利尤单抗能明显改善AD模型小鼠的皮损,且剂量依赖性降低皮损组织中IL-4、IL-13Rα1、 TLR3的蛋白表达。

Objective To explore the impact of dupilumab on TLR3 expression in a mouse model of atopic dermatitis(AD).Methods Thirty-two BALB/c mice(6 weeks old,approximately 24 g) were randomly divided into four groups:normal control(NC),AD,dupilumab 10 mg/kg and dupilumab 25 mg/kg groups,with 8 mice in each group.The NC group mice had ethanol applied to both ears,while the other groups had 2 nmol/L MC903 applied to both ears once daily for 14 days to induce AD.After the two-week modeling period,the dupilumab groups received subcutaneous injections of dupilumab at doses of 10 mg/kg and 25 mg/kg,respectively,and twice every week.The AD group and NC group were given intraperitoneal injection of 0.9% normal saline,and the mice in the four groups were intervened for 1 week,and the mice were sacrificed and tissues collected after 1 week.Histopathological features of skin lesions were observed using HE staining,and the number of mast cells in skin lesions was assessed by toluidine blue staining.Protein expression of IL-4,IL-13Rα1 and TLR3 in skin lesions was detected by IHC and Western blot,respectively.Results The AD group mice exhibited typical atopic dermatitis-like skin lesions and corresponding histopathological changes.In the dupilumab groups,mice showed a noticeable reduction in erythema,decreased epidermal hyperplasia,and reduced inflammatory cell infiltration compared to the AD group.Compared to the NC group,the expression of IL-4,IL-13Rα1 and TLR3 was elevated in the skin lesions of the AD group,while the dupilumab groups showed decreased expression of IL-4,IL-13Rα1 and TLR3 compared to the AD group.Conclusion Subcutaneous injection of dupilumab significantly improved skin lesions in a mouse model of atopic dermatitis,and the improvement was dose-dependent,accompanied by a decrease in the protein expression of IL-4,IL-13Rα1 and TLR3.