儿童重症肺炎支原体肺炎中TLR7、TLR9和IFN-Ⅰ的变化及意义

Changes and significance of TLR7/9 and IFN-Ⅰlevels in children with severe mycoplasma pneumoniae pneumonia

目的研究儿童重症肺炎支原体肺炎(SMPP)中Toll样受体7(TLR7)、TLR9和Ⅰ型IFN的变化及意义。方法纳入80例肺炎支原体肺炎(MPP)患儿,分为非重症MPP组(MPP组)和重症MPP组(SMPP组);选择同期于门诊体检的26名健康儿童为健康对照组。收集各组儿童血清,并收集SMPP组影像学检查仅表现为单侧肺实变、肺不张、肺脓肿或肺组织坏死的26例患儿患侧和对侧肺泡灌洗液(BALF),采用ELISA检测血清及BALF中TLR7、TLR9、髓样分化因子88(MyD88)、IFN-α、IFN-β的含量。结果与健康对照组相比,SMPP组和MPP组血清中TLR7、TLR9、MyD88、IFN-α、IFN-β水平均升高,且SMPP组血清中各因子的水平均高于MPP组(P均<0.05)。患侧BALF中TLR7、TLR9、MyD88、IFN-α、IFN-β的水平均高于对侧(P均<0.01)。TLR7和MyD88水平预测SMPP的受试者操作特征曲线的曲线下面积分别为0.709、0.723。结论过度诱导和生成的TLR7、TLR9、IFN-α和IFN-β可能是儿童SMPP发生及局部肺组织严重损伤的致病因素。TLR7、MyD88可以作为SMPP的预测指标以指导临床治疗。

Objective To investigate the changes and significance of Toll-like receptor 7(TLR7),TLR9 and type I interferon(IFN-Ⅰ)in children with severe mycoplasma pneumoniae pneumonia(SMPP).Methods 80 children with mycoplasma pneumoniae pneumonia(MPP)were divided into the non-severe MPP(MPP group)and SMPP groups(SMPP group).26 healthy children who underwent outpatient physical examination were chosen as the control group.Serum samples in each group were collected.In the SMPP group,bronchoalveolar lavage fl uid(BALF)on the affected and contralateral sides of 26 children with unilateral lung consolidation,atelectasis,lung abscess or lung tissue necrosis on imaging examination were collected.The levels of TLR7,TLR9,myeloid differentiation factor 88(MyD88),interferon-α(IFN-α)and IFN-βin the serum and BALF samples were determined by enzyme-linked immunosorbent assay(ELISA).Results The serum levels of TLR7,TLR9,MyD88,IFN-αand IFN-βin the SMPP and MPP groups were significantly higher than those in the control group,and the levels of all cytokines in the SMPP group were significantly higher compared with those in the MPP group(all P<0.05).The levels of TLR7,TLR9,MyD88,IFN-αand IFN-βin the BALF on the affected side were significantly higher than those on the contralateral side(all P<0.01).The area under the receiver operating characteristic curve(AUC)of serum TLR7 and MyD88 levels for predicting SMPP was 0.709 and 0.723.Conclusions Over-induced and generated TLR7,TLR9,IFN-αand IFN-βmay be pathogenic factors for the incidence of SMPP and severe local lung tissue injury in children with SMPP.TLR7 and MyD88 can be used as predictors of SMPP to guide clinical treatment.