结核杆菌抗原诱导的人γδT细胞表达L-选择素的调控机制  

The modulatory mechanism on the L-selectin expression from activated human γδT cells induced by Mycobacterium tuberculosis peptide antigen

作　　者：武文娟[1] 李柏青[2] 

机构地区：[1]蚌埠医学院生物化学与分子生物学教研室,蚌埠233030 [2]安徽省感染与免疫重点实验室(蚌埠医学院)

出　　处：《现代免疫学》2006年第5期413-417,共5页Current Immunology

基　　金：国家自然科学基金资助项目(3007021);安徽省高校省级重点科研资助项目(2004sys008);蚌埠医学院科研基金资助项目(BY0508)

摘　　要：采用CD62L生物素-链霉亲和素染色流式细胞术检测L-选择素在细胞表面表达的方法，分别观察新鲜PBMC和刺激后培养3～21d的γδT细胞表面L-选择素的表达，并研究培养6～7d的MtbAT预先用LY294002（PI3K途径抑制剂）、SB203580（p38途径抑制剂）、PD98059（MEK抑制剂）分别处理20min，然后用Mtb-Ag再刺激3h时γδT细胞表面L-选择素的表达情况。结果显示新鲜PBMC中γδT细胞L-选择素的表达率为（43．9％±6．7％），γδT细胞L-选择素的表达率为（76．6％±7．9％），有显著差异（P〈0．05）。用Mtb-Ag激活后培养第6天时L-选择素在γδT细胞的表达达到高峰（90．7％）；以后L-选择素表达逐渐下降，15～21dγδT细胞L-选择素的表达在低水平（16．2％～10．6％）维持；Mtb—Ag再刺激MtbAT诱导γδT细胞L-选择素表达下调为69．5％，预先加入LY294002或PD98059，则L-选择素表达率分别为83．1％和78．7％；而加入SB203580未见明显影响。提示γδT细胞活化时L-选择素表达调控与PI3K、Ras／Erk途径有关，但与p38MAPK途径无关。The expression of L-selectin on the surface of γδT cells induced by Mycobacterium tuberculosis peptide antigen （Mtb- Ag） in fresh PBMC cultures cultivated for 3-21 days was detected by means of the flow cytometry （FCM） with the CD62L-biotin-streptavidin RED-670 staining, in which the Mtb-Ag-induced cell cultures cultivated for 6-7 days were pre-treated with SB203580 （an inhibitor for p38 pathway）, LY294002 （an inhibitor for PI3K pathway） or PD980590 （an hihibitor for MEK） for 20 minutes and then restimulated with Mtb-Ag for 3 hours. It was demonstrated that the percentage of L-selectin from γδT cells in the fresh PBMC was significantly lower than that of αβ T cells （43. 9% versus 76. 6%）. The expression of CD62L reached its climax on day 6 of γδT cell cultures （90. 7%）, then decreased and maintained at lower level . Meanwhile, the expression of L-selectin from γδT ceils maintained at lower level from 15-21 days （16.2%-10.6%）, but it was down-regulated to 69.5%, when the Mtb-Ag induced γδT cells was restimulated with Mtb-Ag. In addition, pretreatment of the Mtb-Ag induced ceils with LY294002 or PD98059 could induce the appearance of the L-selectin expression rates of 83.1% and 78.7 respectively, but no any influence could be observed when pretreated with SB203580. These results suggest that the signal pathways including PI3K and Ras/Erk, but not p38 MAPK, participate in the L-selectin expression from activated human γδT cells restimulated by Mycobacterium tuberculosis peptide antigen.

关 键 词：L-选择素 ΓΔT细胞 结核杆菌抗原 信号转导 

分 类 号：R329.25[医药卫生—人体解剖和组织胚胎学]