p53和NF-κB信号通路在MTB感染AECⅡ细胞中的免疫调控作用研究  

Immunomodulatory effects of p53 and NF-κB signaling pathways in AECⅡcells infected with MTB

作　　者：蔡玉荣 王媛[1] 孔云逸 曾瑾[1] 王娟[1] 高蔚丰[1] 李勇(指导)[2] CAI Yurong;WANG Yuan;KONG Yunyi;ZENG Jin;WANG Juan;GAO Weifeng;LI Yong(Key Laboratory of Ministry of Education for Conservation and Utilization of Special Biological Resources in the Western China,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学西部生物资源保护与利用教育部重点实验室,银川750021 [2]宁夏大学生命科学学院,银川750021

出　　处：《中国免疫学杂志》2022年第7期769-776,782,共9页Chinese Journal of Immunology

基　　金：国家自然科学基金项目(31560694);宁夏自然科学基金项目(2018AAC03047,NZ17021)资助。

摘　　要：目的:研究在结核分枝杆菌(MTB)感染肺泡Ⅱ型上皮细胞(AECⅡ)过程中,p53和NF-κB信号通路中相关信号分子是否参与了抗结核的先天免疫调控。方法:利用实时荧光定量PCR、Western blot和蛋白芯片技术,通过过表达和抑制AECⅡ细胞中的p53和NF-κB基因,分析在牛结核分枝杆菌弱毒株卡介苗(BCG)感染过程中p53和NF-κB信号通路的信号分子和细胞炎症因子的表达变化,并探讨p53与NF-κB信号通路在AECⅡ细胞抗MTB感染免疫应答中的“cross-talk”关系。结果:在A549细胞中,p53信号通路通过p53协同CBP来负调控NF-κB、TLR-4及TRAF6的表达,从而抑制NF-κB信号通路的活化,并上调IL-6、IL-8、TNF-α、IFN-γ的表达;而NF-κB信号通路通过NF-κB协同TLR-4、TRAF6与CBP来负调控p53与MDM2的表达,从而抑制p53信号通路的激活,同时上调了IL-6、IL-8、TNF-α、IFN-γ的表达。当BCG感染A549细胞时,p53信号通路中p53协同MDM2负调控CBP,进而上调NF-κB信号通路的TLR-4和TRAF6;同时,NF-κB信号通路通过TLR-4和TRAF6协同MDM2、CBP活化p53信号通路;细胞炎症因子IL-6、IL-8、TNF-α、IFN-γ的表达均显著上调。结论:在AECⅡ细胞中p53信号通路与NF-κB信号通路间存在拮抗作用;当受到BCG刺激时,p53信号通路与NF-κB信号通路表现出协同参与AECⅡ细胞抗MTB感染的免疫调控作用,本研究为深入探讨p53和NF-κB信号通路在肺泡上皮细胞抗结核中的免疫调控机制提供了理论参考。Objective:To investigate whether relevant signaling molecules in the p53 and NF-κB signaling pathways are involved in the innate immune regulation of anti-tuberculosis during mycobacterium tuberculosis(MTB)infection of AECⅡcells.Methods:The expression of signaling molecules and cellular inflammatory factors of p53 and NF-κB signaling pathways during BCG infection of AECⅡcells which overexpressed or knocked down of p53 and NF-κB genes was analyzed by real-time fluorescent quantitative PCR,Western blot and protein microarray techniques.The"cross-talk"relationship between p53 and NF-κB signaling pathway in the immune response of AECⅡcells against MTB infection was also explored.Results:In A549 cells,p53 and CBP of the p53 signaling pathway negatively regulated the expressions of NF-κB,TLR-4 and TRAF6,inhibiting the activation of NF-κB signaling pathway and upregulating the expressions of IL-6,IL-8,TNF-α,IFN-γ.However,the NF-κB signaling pathway negatively regulated the expressions of p53 and MDM2 through NF-κB,TLR-4,TRAF6 and CBP,thereby inhibiting the activation of the p53 signaling pathway and upregulating the expressions of IL-6,IL-8,TNF-α,and IFN-γ.The p53 cooperated with MDM2 of p53 signaling pathway negatively regulated CBP in A549 cells infected with BCG,which in turn upregulated TLR-4 and TRAF6 of NF-κB signaling pathway.Meanwhile,TLR-4 and TRAF6 of NF-κB signaling pathway cooperated with MDM2 and CBP activated p53 signaling pathway.And the expression of IL-6,IL-8,TNF-α,and IFN-γwere significantly upregulated.Conclusion:The p53 signaling pathway and NF-κB signaling pathway are antagonistic in AECⅡcells.Upon stimulation of BCG,the p53 signaling pathway together with the NF-κB signaling pathway are involved in the immune regulation of AECⅡcells against MTB infection.This study provides theoretical reference for indepth study of the immune regulatory mechanism of p53 and NF-κB signaling pathway in alveolar epithelial cells against tuberculosis.

关 键 词：结核分枝杆菌 AECⅡ细胞 P53 NF-ΚB 免疫调控 

分 类 号：R392.[医药卫生—免疫学]