人γδ T细胞表型与功能特征的探讨  

Evaluation of phenotypic and functional characteristics of human γδ T cells

作　　者：李丽[1] 吴长有[1] 

机构地区：[1]中山大学医学院免疫学教研室热带传染病教育部重点实验室,广州510080

出　　处：《免疫学杂志》2008年第6期609-612,617,共5页Immunological Journal

基　　金：国家973项目(2007CB512404)

摘　　要：目的比较观察人外周血PBMCs和CBMCs中αβT和γδT细胞的表型与功能特征,进一步了解γδT细胞在免疫应答中的作用。方法分离正常人PBMCs及脐带血CBMCs,检测表面分子的表达。PMA+Ionomycin刺激PBMCs或CBMCs后,利用流式细胞术(FCM)检测其细胞因子的产生以及初始/记忆细胞标记的表达。结果与αβT细胞相比,γδT细胞高表达CD45RO,低表达CD25和CCR7;与CBMCs中γδT细胞相比,PBMCs中γδT细胞表达CD45RO升高,CD45RA与CD25降低。细胞因子表达的结果表明,与αβT细胞相比,γδT细胞分泌大量IFN-γ和TNF-α,较少分泌IL-2,且IFN-γ+细胞主要为CD45RA-CD62L-CCR7-;与PBMCs中γδT细胞不同,体外刺激CBMCs中γδT细胞后,表达IFN-γ数量较低,且IFN-γ+细胞主要为CD45RA+CD62L-CCR7-/+。结论PBMCs与CBMCs中αβT和γδT细胞的表型与功能均存在差别,记忆性γδT细胞的增加可能与其活化和免疫应答的作用相关。Objective To compare the phenotypic and functional characteristics of αβ and γδ T cells in peripheral blood mononuclear cells （PBMCs） as well as cord blood mononuclear cells （CBMCs）, and to elucidate the role of γδ T cells in immune responses. Methods PBMCs and CBMCs were isolated, and then surface markers and intracellular cytokines were detected by flow cytometry directly or after stimulation with PMA plus ionomycin. Results γδ T cells expressed higher levels of CD45RO and diminished levels of CD25 and CCR7 compared with αβ T cells. γδ T cells in PBMCs expressed higher levels of CD45RO as well as lower levels of CD45RA and CD25 compared with γδ T cells in CBMCs. After in vitro short term stimulation, γδ T cells expressed large amount of IFN-γ and TNF-α but little IL-2-compared with αβ T cells. In addition, the majority of γδ^＋ IFN-γ^＋ were CD45RA^- CD62L^- CCR7^- . Different from what observed in PBMCs, γδ T cells in CBMCs produced much less IFN-γ after in vitro stimulation, and γδ^＋ IFN-γ^＋ cells were mainly CD45RA^＋ CD62L^- CCR7^-/＋. Conclusion The phenotypic and functional characteristics of γδ T cells are different from αβ T cells in PBMCs and CBMCs. The increase of memory γδ cells may be related to its activation and function in immune responses.

关 键 词：γδ T细胞 表型 细胞因子 

分 类 号：R392.1[医药卫生—免疫学]