TM-TNF-α介导的反向信号协同增强sTNF-α对U937细胞的激活作用  

Reverse signaling by TM-TNF-α augments the activation of U937 induced by sTNF-α

作　　者：辛利军[1] 石文芳[1] 李清芬[1] 姜晓丹[1] 冯玮[1] 熊平[1] 徐勇[1] 龚非力[1] 李卓娅[1] 

机构地区：[1]华中科技大学同济医学院免疫学系,武汉430030

出　　处：《中华微生物学和免疫学杂志》2005年第1期44-47,共4页Chinese Journal of Microbiology and Immunology

基　　金：国家自然科学基金重点课题资助项目 (3 963 0 3 2 0 )

摘　　要：目的　用sTNFRⅠ预先激活TM TNF α介导的反向信号 ,观测其对sTNF α激活单核细胞系U937细胞的影响。方法　预先用sTNFRⅠ与U937细胞作用 30min ,洗涤后加入sTNF α作用不同时间 ,观测预激活反向信号对sTNF α刺激U937产生活性氧、胞内促炎细胞因子TNF α、IL 1 β、IL 8mRNA的转录及IκB α水平 (Westernblot)的影响。结果　单独用sTNFRⅠ激活的反向信号并不影响U937细胞的功能 ,而预激活反向信号能协同增强sTNF α刺激U937细胞产生活性氧 ,且呈sTNFRⅠ浓度、sTNF α浓度依赖关系 ;预激活反向信号协同增强sTNF α刺激U937炎性细胞因子mRNA(TNF α、IL 1 β、IL 8等 )的转录水平 ;并促进U937细胞IκB α的降解。结论　预先激活TM TNF α介导的反向信号协同增强sTNF α对U937的激活作用 ,提示反向信号可能参与机体对早期炎症反应的调节。Objective To investigate the effect of reverse signaling by transmembrane TNF-α (TM-TNF-α) on the activation of U937 induced by sTNF. Methods U937 cells were pre-incubated with sTNFRⅠ for 30 min and then stimulated with sTNF-α for different time. The biological activities of U937 cells, including the production of active oxygen, the transcription of intracellular pro-inflammatory cytokines, such as TNF-α, IL-1β, IL-8 mRNA, and expression of cytoplasmic IκB-α were measured. Results sTNFRⅠ alone did not influence the biological activities of U937 cells. Reverse signaling through TM-TNF induced by sTNFRⅠ promoted sTNF-stimulated U937 produce more active oxygen, which is dose-dependant of sTNFRⅠ and sTNF-α. Reverse signaling also enhanced mRNA transcription of cytokines such as TNF-α, IL-1β and IL-8 and accelerated the degradation of IκB-α. Conclusion Reverse signaling by TM-TNF-α induced by sTNFRⅠ augment with activation of U937 stimulated with sTNF, suggesting that reverse signaling may be involved in the regulation of early inflammation.

关 键 词：TNF-α U937细胞 TNFR 激活作用 预激 介导 IL-8 转录水平 RNA 刺激 

分 类 号：R392[医药卫生—免疫学]