细菌溶解产物口服治疗通过影响T细胞平衡改善PM2.5所致大鼠气道炎症

Oral medication of bacterial lysates ameliorates PM2.5 exposure-induced airway inflammation by regulating Th cell immune balance in rats

目的本研究旨在从Th1/Th2及Th17/Treg平衡轴的角度探讨PM2.5暴露及细菌溶解产物Broncho-Vaxom(BV)治疗与健康大鼠气道炎症的关系。方法PM2.5暴露组鼻内滴注PM2.5混悬液,口服生理盐水;BV治疗组暴露与PM2.5暴露组相同,口服BV溶液;对照组均用生理盐水代替。对大鼠鼻黏膜进行组织病理学检查;用流式细胞仪和酶联免疫吸附试验(ELISA)检测Th1/Th2/Th17/Treg细胞的表达和功能。结果PM2.5暴露组大鼠鼻黏膜出现炎症细胞浸润;Th2细胞和Th17细胞显著上调,Treg细胞显著下调;血清中相关细胞因子IL-4、IL-5、IL-13及IL-17显著升高,IFN-γ和IL-10显著下降。BV干预后鼻黏膜炎性细胞浸润减少、Th细胞相关免疫失衡减轻。结论PM2.5可诱导健康大鼠产生气道炎症,PM2.5暴露所诱导的气道炎症可能与Th1/Th2和Th17/Treg细胞免疫失衡有关,BV可减轻PM2.5诱导的气道炎症及Th细胞相关免疫失衡。

Atmospheric particulate matter(PM)is the primary pollutant of air quality in most cities of China.This study was designed to explore the relationship of PM2.5 exposure and bacterial lysate Broncho-Vaxom(BV)treatment with airway inflammation in healthy rats from the perspective of Th1/Th2 and Th17/Treg balance.In the PM2.5 exposure group,PM2.5 suspension was instilled intranasally for 15 consecutive days,and normal saline was orally administered on the 16th to 90th days.The treatment of the BV treatment group on days 1-15 was the same as that of the PM2.5 exposure group,and oral BV solution was given on days 16-90.In the control group,normal saline was used instead of nasal drip and oral phase.The rat nasal mucosa was stained with HE to evaluate the degree of airway inflammation.Flow cytometry and ELISA were used to detect the expression and function of Th1/Th2/Th17/Treg cells.Data showed that the nasal mucosa of rats in the PM2.5 exposure group demonstrated inflammatory cell infiltration.Th2 cells and Th17 cells in the PM2.5 exposure group were significantly up-regulated,and Treg cells were significantly down-regulated;cytokines IL-4,IL-5,IL-13 and IL-17 were significantly increased,and IFN-γand IL-10 were significantly decreased.After BV intervention,inflammatory cell infiltration of the nasal mucosa was reduced,and Th cell-related immune imbalance was ameliorated.Taken together,PM2.5 can induce airway inflammation in healthy rats,and the airway inflammation induced by PM2.5 exposure may related to the immune imbalance of Th1/Th2 and Th 17/Treg cells.BV can reduce PM2.5-induced airway inflammation and Th cell related immune imbalance.