NKT细胞在MRSA感染性肺炎中作用的初步研究  

Preliminary study on role of NKT cells in MRSA infectious pneumonia

作　　者：侯晓睿 黄钊霞 易夏玉 朱平 刘北一(指导) HOU Xiaorui;HUANG Zhaoxia;YI Xiayu;ZHU Ping;LIU Beiyi(Department of Immunology,School of Basic Medical Sciences,Southern Medical University,Guangdong Provincial Key Laboratory of Functional Proteomics,Guangzhou 510515,China)

机构地区：[1]南方医科大学基础医学院免疫学教研室,广东省功能蛋白质组学重点实验室,广州510515

出　　处：《中国免疫学杂志》2023年第9期1803-1808,共6页Chinese Journal of Immunology

基　　金：广东省基础与应用基础研究基金项目(2021A1515011229);广东省医学科学技术研究基金项目(B2022119)。

摘　　要：目的:初步探讨NKT细胞在耐甲氧西林金葡菌(MRSA)感染性肺炎模型中的作用。方法:MRSA经鼻黏膜感染C57BL/6野生型(WT)小鼠和CD1d^(-/-)小鼠。观察小鼠生存率,检测肺组织中细菌载量,ELISA检测肺组织中细胞因子TNF-α、IFN-γ、IL-17、IL-6含量,流式细胞术检测肺组织中CD3^(+)CD8^(+)T细胞、NK细胞和NKT细胞百分比。结果:MRSA致死剂量感染5 d,WT小鼠生存率显著低于CD1d^(-/-)小鼠(46.2%vs 90.0%,P<0.05)。感染12~48 h,WT小鼠肺组织中细菌载量显著高于CD1d^(-/-)小鼠(P<0.01);WT小鼠肺组织中TNF-α、IFN-γ、IL-6和IL-17含量较CD1d^(-/-)小鼠明显增高(P<0.01)。MRSA感染24 h,WT小鼠肺组织中NKT细胞、NK细胞百分比显著高于CD1d^(-/-)小鼠(P<0.01),而CD3^(+)CD8^(+)T细胞百分比低于CD1d^(-/-)小鼠(P<0.01)。结论:在MRSA肺炎中,NKT细胞被激活,从而加重肺部炎症反应,降低生存率,减缓细菌清除。Objective:To explore the role of NKT cells in pneumonia model infected by methicillin-resistant Staphylococcus aureus(MRSA).Methods:C57BL/6 mice(wild-type,WT)and CD1d^(−/−)mice were infected with MRSA via intranasal,respectively.Survival rate was examined for mice,the bacteria load was measured,and the level of cytokines,including TNF-α,IFN-γ,IL-17 and IL-6 in lung homogenate were determined by ELISA.Percentages of CD3+CD8+T cells,NK cells,and NKT cells in lung tissue were detected by flow cytometry,respectively.Results:The 5-day survival rate of WT mice was significantly lower than that of CD1d^(−/−)mice(46.2%vs 90.0%,P<0.05).Bacterial load in lung homogenate of WT mice was significantly higher than that of CD1d^(−/−)mice(P<0.01).Levels of TNF-α,IFN-γ,IL-6 and IL-17 in lung homogenate of WT mice were also significantly higher(P<0.01).After 24 h infection,percentages of NKT cells and NK cells in lung of WT mice were significantly higher than that of CD1d^(−/−)mice(P<0.01),while percentage of CD3+CD8+T cells was significantly lower as compared to CD1d^(−/−)mice(P<0.01).Conclusion:In MRSA pneumonia mice,NKT cell activation may promote pulmonary and systemic proinflammatory response,reduce survival rate and slow the bacterial clearance.

关 键 词：NKT细胞 CD1D 耐甲氧西林金葡菌(MRSA) 肺炎 

分 类 号：R392.12[医药卫生—免疫学]