呼吸道合胞病毒毛细支气管炎患儿中TREM-1/DAP12通路关键信号节点的表达

Expression of the key proteins in TREM-1/DAP12 signaling pathway in children with respiratory syncytial virus bronchiolitis

目的探讨呼吸道合胞病毒(RSV)毛细支气管炎患儿中TREM-1/DAP12蛋白的表达及该通路与炎症反应的潜在关联。方法选取2017年1月—2019年1月四川省广安市人民医院RSV毛细支气管炎患儿作为病例组(分为轻症组和重症组),选取同期体检的健康儿童作为对照组,对血清中炎症因子含量及外周血单个核细胞(PBMCs)中TREM-1、DAP12表达进行检测。构建RSV感染人支气管上皮(NHBE)细胞的体外细胞模型,将人支气管上皮细胞(NHBE)分为对照组、RSV感染组、RSV+siRNA-Control组和RSV+siRNA-TREM-1组,并对细胞中TREM-1、DAP12的表达及上清液中炎症因子含量进行检测。结果轻症组、重症组儿童血清中白细胞介素-1β(IL-1β)等炎症因子含量、PBMCs中TREM-1、DAP12表达量均高于对照组,且重症组高于轻症组(均P<0.05)。RSV感染组、RSV+siRNA-Control组TREM-1、DAP12表达量均高于对照组、RSV+siRNA-TREM-1组(均P<0.05)。RSV+siRNA-TREM-1组上清液中炎症因子含量均低于RSV感染组、RSV+siRNA-Control组(均P<0.05)。结论TREM-1/DAP12信号通路在RSV毛细支气管炎患儿中高表达。RSV诱导NHBE细胞高表达TREM-1,沉默TREM-1可以下调DAP12表达,抑制炎症因子分泌。

Objective To investigate expression of TREM-1/DAP12 protein in children with respiratory syncytial virus(RSV)bronchiolitis as well as potential relationship between this pathway and inflammation.Methods From January 2017 to January 2019,children with RSV bronchiolitis in Guangan People’s Hospital of Sichuan Province were selected as case group(they were divided into mild group and severe group),healthy children who had physical examination during the same period were selected as control group,levels of inflammatory factors in serum and expression of TREM-1 and DAP12 in peripheral blood mononuclear cells(PBMCs)were detected.In vitro cell model of human bronchial epithelial(NHBE)cells infected by RSV was constructed,NHBE cells were divided into control group,RSV-infected group,RSV+siRNA-Control group and RSV+siRNA-TREM-1 group.Expression of TREM-1 and DAP12 in cells as well as level of inflammatory factors in supernatant were detected.Results Serum levels of inflammatory factors such as interleukin-1β(IL-1β)and expression levels of TREM-1 and DAP12 in PBMCs in children in mild and severe groups were both higher than those in control group,and severe group were higher than mild group(all P<0.05).The expression of TREM-1 and DAP12 in RSV-infected group and RSV+siRNA-Control group were both higher than control group and RSV+siRNA-TREM-1 group(both P<0.05).Levels of inflammatory factors in supernatant of RSV+siRNA-TREM-1 group were all lower RSV-infected group and RSV+siRNA-Control group(all P<0.05).Conclusion TREM-1/DAP12 signaling pathway is highly expressed in children with RSV bronchiolitis.RSV induces overexpression of TREM-1 in NHBE cells,and silencing TREM-1 can down-regulate DAP12 expression and inhibit the secretion of inflammatory factors.