健康青年人HCMV特异性CD8^+T细胞频率和表型分析  

Frequency and phenotype analysis of human cytomegalovirus specific CD8^+ T cells in healthy young donors

作　　者：查庆兵[1] 徐丽慧[2] 刘芳[3] 孙荭[1] 贾仟涛[1] 李丰耀[1] 何贤辉[1] 

机构地区：[1]暨南大学生命科学技术学院组织移植与免疫实验中心 [2]暨南大学生物工程研究所 [3]暨南大学附属第一医院临床实验中心,广州510632

出　　处：《免疫学杂志》2007年第3期260-264,269,共6页Immunological Journal

基　　金：国家自然科学基金重点项目(30230350);国家自然科学基金面上项目(30371651;30572199)资助

摘　　要：目的利用负载pp65495-503抗原肽的HLA-A*0201四聚体染色结合流式细胞术,分析HLA-A2+健康青年供者外周血中HCMV pp65495-503特异性记忆CD8+T细胞的频率和表型。方法以优化的四聚体染色方法对22例中国青年供者全血进行染色,用流式细胞仪对样品进行三色荧光分析。结果健康中国青年人外周血中存在高频率的pp65495-503特异性CD8+T细胞,占CD8+T细胞的百分率为0.14~6.84%(均数2.45%);表型分析显示其CD28+细胞占四聚体阳性和四聚体阴性细胞的百分率分别为为32.5%(±21.7%)和58.58%(±10.4%)(P<0.001);CD57+细胞占四聚体阳性和四聚体阴性细胞的百分率分别为55.8%(±18.4%)和27.4%(±8.3%)(P<0.001)。同时,对三例健康青年人CD8+T细胞上多种表面分子的详细分析显示,pp65495-503特异性记忆CD8+T细胞有不同比率的细胞表达CD62L、CD45RO、CD38和CD27,而且还有一定比例的细胞表达CD45RA,但不表达活化抗原CD69分子。结论青年中国人外周血中存在高频率的HCMV特异性CD8+T细胞,这些细胞的表型存在高度异质性,可能是处于不同分化阶段的记忆和效应细胞群体组成。Objective To analyze the frequencies and phenotypes of CD8^＋T cells specific for human eytomegalovirus （HCMV） structural protein pp65-derived peptide （pp65495-503, NLV） in HLA-A2^＋young Chinese donors by using HLA-A2/NLV tetramer staining and flow cytometry.Methods Peripheral whole blood samples from 22 HLA-A2^＋donors were stained with HLA-A2/NLV tetramer and analyzed by tricolor flow cytometry.Results The frequencies of pp65495-503-specific CD8^＋T cells within total CD8^＋T cell population were between 0.14% and 6. 84 % （mean 2.45 % ） in the healthy young donors. The percentages of CD28^＋cells within tetramer-positive and -negative CD8^＋T cell populafious were （32.5%±1.7% ） and （58.58%±18.4% ）respectively, while CD57^＋ cells within these two cell pools were （55.8%±10.4% ） and （27.4%±8.3% ） respectively, with significant difference between the two groups （ P 〈 0.001 ）. Furthermore, the expression levels of other surface markers of three donors showed that different proportions of tetramer-positive CD8^＋T cells expressed CD62L, CD27, CD45RO, and CD38. In addition, a significant part of tetramer-positive CD8^＋T cells expressed CD45RA, whereas no significant CD69 expression was detected. Conclusion High frequencies of HCMV-specific CD8^＋T cells exist in the healthy young Chinese individuals. These cells are heterogeneous in phenotypes, suggesting that they may be composed of the memory and effector T cells at various differentiated stages.

关 键 词：四聚体技术 人巨细胞病毒 记忆型CD8^+T细胞 流式细胞术 

分 类 号：R392.12[医药卫生—免疫学]