ERK1/2信号传导途径参与调控NK细胞的杀伤活性  

Signal transduction pathway ERK1/2 involved in cytotoxicity of NK cell lines

作　　者：梁淑娟 孙汭[1] 魏海明[1] 冯进波[1] 许晓群[1] 田志刚[2] 

机构地区：[1]中国科技大学免疫学研究所,合肥230027 [2]中国科技大学生命科学院,合肥230027

出　　处：《中国免疫学杂志》2003年第9期591-594,598,共5页Chinese Journal of Immunology

基　　金：国家自然科学基金 ( 3 9970 82 8;3 9870 2 9;3 9970 64 9);国家杰出青年科学基金 ( 3 0 12 5 0 3 8);国家科技部"973"项目 ( 2 0 0 1CB5 10 0 10 );中国科学院知识创新工程重大项目 (KSCX2 2 0 8)

摘　　要：目的 :阐明NK细胞系持续活化的信号通路ERK1 2在调节NK细胞增殖和杀伤活性中可能发挥的作用。方法 :制备NK 92和YT细胞的全细胞提取物 ,进行Westernblot,检测在细胞系中持续活化的信号传导途径 ,信号通路特异性阻断剂PD0 980 5 9阻断ERK1 2活化 ,MTT方法评价ERK1 2在调节NK细胞杀伤和增殖活性中发挥的作用 ,RT PCR检测阻断试剂作用前后杀伤相关分子表达水平的变化。结果 :2个代表性的NK细胞系 (YT ,IL 2非依赖 ;NK 92 ,IL 2依赖 )中存在ERK1 2 (p4 4 4 2MAPK)、NF κB和STAT3信号通路的持续磷酸化 ,去除IL 2和血清较长时间后仍保持活化状态 ,而其它信号途径 (STAT1、STAT6、PI 3K、p38MAPK)则未见活化。特异性阻断剂PD0 980 5 92 0 0 μmol L阻断ERK1 2活化后 ,NK细胞杀伤K5 6 2靶细胞的能力显著降低 ,但细胞的增殖活性不受影响。RT PCR证实 ,PD0 980 5 9阻断ERK1 2抑制NK细胞毒活性的同时 ,杀伤相关分子IFNγ、FasL、perforin的表达水平也不同程度地下调。结论 :NK细胞系中持续性活化的ERK1 2主要传递与NK细胞细胞毒性相关的信号 ,并不参与调节细胞的增殖 ,该途径通过控制杀伤相关分子IFNγ、FasL、perforin的基因表达从而主导NK对靶细胞的杀伤。Objective:To determine the roles of constitutively activated signal transduction pathway ERK1/2(p44/42 MAPK)in controlling cytotoxicity or proliferation activity of natural killer cell lines.Methods:Whole cell extracts from human NK cell lines(YT,IL 2 independent;NK 92,IL 2 dependent) was used in Western blot to detect the constitutively activated signal transduction pathway(s) in human NK cell lines. Specific inhibitor PD098059 was used to abrogate phosphorylation of ERK1/2 for further evaluation. A MTT based method was applied to analyze the cytotoxicity and proliferation capability of NK cell lines before and after specific inhibition of ERK1/2 activation by PD098059.RT PCR protocol was applied to analyze the cytotoxic related molecules possibly engaged with the ERK1/2 signal transduction pathway.Results:Western blot showed that signal transduction pathway ERK1/2,NF κB and STAT3 was constitutively phosphorylated in two representative human NK cell lines YT and NK 92 which killed NK sensitive K562 target efficiently,other sigal pathways(STAT1,STAT6,p38 MAPK and PI 3K) were not activated.ERK1/2 inhibitor PD098059 apparently inhibited cytotoxicity of NK cell lines but did not influence their proliferation potential, RT PCR analysis revealed that the expression of lytic related molecules including IFNγ,FasL,and perforin was downregulated to distince degree by PD098059 as it blocked the phosphorylation of ERK1/2 in NK cell lines.Conclusion:The constitutively phosphorylated signal pathway ERK1/2 in NK cell lines mainly involved in transducing signals controlling the cytotoxic capacity but not the proliferation potential of NK cells,ERK1/2 regulated the lytic capacity of NK cells by inducing the expression level of lytic related molecules including IFNγ、FasL and perforin. [

关 键 词：ERK1/2 信号传导途径 调控 NK细胞 杀伤活性 细胞免疫学 

分 类 号：R392.12[医药卫生—免疫学]