肺炎链球菌表面蛋白A诱导人中性粒细胞生产CXCL8的机制  

Mechanisms of up-reguation of chemokine CXCL8 in human neutrophils induced by Streptococcus pneumoniae surface protein A

作　　者：徐蕾[1] 陈丹 甘萍[3] 曹炬[4] 

机构地区：[1]重庆医科大学病原生物学教研室,重庆400016 [2]重庆建设医院药剂科,重庆400050 [3]重庆三峡中心医院儿童分院儿内科,重庆404000 [4]重庆医科大学附属第一医院检验科,重庆400016

出　　处：《细胞与分子免疫学杂志》2013年第1期14-17,共4页Chinese Journal of Cellular and Molecular Immunology

摘　　要：目的研究肺炎链球菌表面暴露的毒性表面蛋白A(PspA)促进CXCL8分泌的可能机制。方法使用炎症相关的信号分子NF-κB、p38MARK、ERK、JNK的抑制剂预处理人嗜中性粒细胞后,观察PspA对CXCL8分泌作用的影响。从受PspA刺激的人嗜中性粒细胞中分别提取细胞总蛋白和细胞核提取物,用ELISA法测定p38MAPK蛋白的活力和NF-κB的浓度的改变,并且采用Western blot方法进一步验证PspA对p38MAPK和IkB-α蛋白磷酸化水平的影响。结果使用NF-κB,p38MARK的抑制剂预处理人嗜中性粒细胞后,可以扭转PspA促中性粒细胞分泌CXCL8的现象;而ERK,JNK的抑制剂无此效果。另一方面,PspA可以上调中性粒细胞中的P38 MAPK蛋白的含量和NF-κB的浓度,也可以提高p38MAPK和NF-κB通路抑制蛋白IkB-α的磷酸化水平。结论肺炎链球菌PspA诱导人体中性粒细胞释放CXCL8受p38蛋白和NF-κB途径的调控。Objective To study the mechanisms by which pneumococcal surface protein A （PspA） up-regulates chemokine CXCL8 in human neutrophils. Methods Human neutrophils were treated by the inhibitors of NF-kB, p38MARK, ERK, JNK respectively, and then CXCL8 concentration in the cell-free supernatants after stimulation with PspA was measured by ELISA. The total cellular proteins and nuclear extracts of neutrophils after stimulation with PspA were prepared to detect p38MARK and NF-kB contents by ELISA. The total cellular proteins were also used for the determination of the phosphorylation levels of p38MAPK and IkB-α by Western blotting. Results NF-kB or p38MARK inhibitor instead of ERK or JNK inhibitor significantly suppressed the release of CXCL8 induced by PspA. In addition, PspA also increased the activity of p38MAPK and the concentration of NF-KB in the neutrophils. Western blotting indicated that PspA enhanced the phosphorylation levels of p38MAPK and IkB-α. Conclusion The secretion of CXCL8 in human neutrophiis induced by PspA is regulated by p38MAPK and NF-kB pathways.

关 键 词：肺炎链球菌 中性粒细胞 CXCL8 p38MARK NF-ΚB 

分 类 号：R392.1[医药卫生—免疫学] R378.14[医药卫生—基础医学]