肺炎衣原体假定蛋白Cpn0423通过NOD2信号途径诱导炎症反应的作用机制  

Contribution of NOD2 signal pathway to Chlamydia pneumonia Cpn0423-induced inflammatory response

作　　者：李佳艳[1] 罗良贤[1] 周洲 周安文[1] 何蓓 江扬华 李胜涛[1,3] 吴移谋 陈虹亮 Li Jiayan;Luo Liangxian;Zhou Zhou;Zhou Anwen;He Bei;Jiang Yanghua;Li Shengtao;Wu Yimou;Chen Hongliang(Chlamydia R&D Center of Chenzhou,Chenzhou NO.1 People′s Hospital,Chenzhou 423000,China;Institute of Pathogenic Biology,Hengyang Medical College,University of South China,Hengyang 421001,China;Department of Laboratory Medicine,Chenzhou Hospital Affiliated to Southern Medical University,Chenzhou 423000,China)

机构地区：[1]郴州市第一人民医院,郴州市衣原体疾病防治技术研发中心,423000 [2]南华大学衡阳医学院病原生物学研究所,421001 [3]南方医科大学附属郴州医院检验医学中心,423000

出　　处：《中华微生物学和免疫学杂志》2020年第9期690-696,共7页Chinese Journal of Microbiology and Immunology

基　　金：国家自然科学基金(81802022);湖南科技厅计划项目(2018SK50309);郴州市科技局(yfzx201908,zdyf201941)。

摘　　要：目的了解肺炎衣原体(Chlamydia pneumoniae,Cpn)假定蛋白Cpn0423的生物学活性及其诱导宿主细胞炎症反应的作用途径。方法生物信息学软件初步分析Cpn0423的生物学特性,激光共聚焦显微技术检测核苷酸结合寡聚化结构域样受体2(nucleotide-binding oligomerization domain-like receptor 2,NOD2)在骨髓源性的巨噬细胞(bone marrow-derived macrophages,BMDMs)中的亚细胞定位。采用NOD2-siRNA干扰试验检测其抑制BMDMs细胞中NOD2的表达水平,ELISA法检测Cpn0423诱导BMDMs细胞分泌的巨噬细胞炎性蛋白2(MIP-2)和IL-6,PCR法检测Cpn阳性患者支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF)中Cpn0423 DNA水平。结果Cpn0423与衣原体Ⅲ型分泌系统效应蛋白同源性为85%~93%。NOD2-siRNA能有效抑制BMDMs细胞中NOD2 mRNA的表达水平。NOD2-siRNA干扰后,Cpn0423诱导BMDMs细胞分泌的细胞因子MIP-2[(920.5±99.1)pg/ml vs(130.1±11.5)pg/ml,P<0.001]和IL-6[(266.2±58.4)pg/ml vs(165.7±21.5)pg/ml,P<0.001]水平显著降低。83.3%(10/12)Cpn阳性患者BALF中Cpn0423 DNA为阳性,对照组未检出Cpn0423 DNA。结论Cpn0423通过NOD2途径诱导宿主细胞免疫应答,与Cpn引起机体慢性炎症损伤密切相关。Objective To understand and determine the biological properties of Chlamydia pneumonia(Cpn)hypothetical protein Cpn0423 and the mechanisms of which involved in Cpn0423-induced inflammatory response.Methods The biological properties of Cpn0423 gene were analyzed using bioinformatic software.The subcellular localization of nucleotide-binding oligomerization domain-like receptor 2(NOD2)in bone marrow-derived macrophages(BMDMs)was detected by confocal microscope.NOD2-siRNA was used to inhibit the expression of NOD2 at mRNA level.Cpn0423-induced macrophage inflammatory protein 2(MIP-2)and IL-6 production in BMDMs were detected by ELISA.PCR was performed to detect Cpn0423 DNA in bronchoalveolar lavage fluid(BALF)of Cpn-positive patients.Results The homology between Cpn0423 and other typeⅢsecretion system effector proteins of Chlamydia ranged from 85%to 93%.NOD2-siRNA could effectively inhibit the expression of NOD2 at mRNA level in BMDMs(P<0.001).Moreover,Cpn0423-induced production of MIP-2[(920.5±99.1)pg/ml vs(130.1±11.5)pg/ml,P<0.001]and IL-6[(266.2±58.4)pg/ml vs(165.7±21.5)pg/ml,P<0.001]in BMDMs were decreased following NOD2-siRNA pre-treatment.Cpn0423 DNA was detected in the BAlF of 83.3%(10/12)of Cpn-positive cases,but not in Cpn-negative cases.Conclusions Cpn0423 induced inflammatory response in host cells through NOD2 pathway,which was closely related to the chronic inflammatory injury caused by Cpn.

关 键 词：肺炎衣原体 Cpn0423 NOD2 炎症反应 

分 类 号：R392[医药卫生—免疫学]