正常人PBMC中T细胞的PD-1表达及其表型分析

目的观察正常人外周血单个核细胞（PBMC）T细胞的PD-1表达,并对其表型进行分析。方法分离正常成年人PBMCs,利用流式细胞术检测CD4、CD8、CD45RA、CD27和PD-1等表面分子的表达;通过对比分析,了解PD-1＋T细胞表型与记忆T细胞的关系。结果正常成年人周围血中CD4＋PD-1＋T细胞和CD8＋PD-1＋T细胞的平均表达水平为（8.71±3.97）%,CD8＋PD-1＋T细胞的频率为（2.44±0.76）%。正常人外周血CD4＋PD-1＋T细胞可分成3个亚群,即初始T细胞（CD45RA＋CD27＋T细胞）、中央记忆型（CD45RA-CD27＋）T细胞和效应记忆型（CD45RA-CD27-）T细胞,其比例分别为（18.5±8.79）%、（65.0±13.84）%和（15.5±5.12）%,而在CD4＋PD-1-T细胞中3种T细胞的比例分别为（68.25±10.33）%、（27.75±9.04）%和（3.0±1.22）%。结论正常人周围血中存在CD4＋PD-1＋T细胞,并且多为中央记忆T细胞,而CD4＋PD-1-T细胞则多为初始T细胞。

The frequencies and phenotypes of PD-1 T cells from human peripheral blood mononuclear cells

Objective To characterize the PD-1＋ T cells in human peripheral blood mononuclear cells （PBMC）. Methods We isolated the mononuclear cells from peripheral blood. Total T cells in the peripheral blood of human were detected by labeling with CD4,CD8,PD-1,CD27 and CD45RA fluorescence-antibodies and analyzed with flow cytometry to understand the expression of PD-1 on the T cells and their phenotype characteristics. Results The frequency of CD4＋ PD-1＋ and CD8＋PD-1＋ T cells from blood donors were（8.71±3.97）% and （2.44±0.76）%,respectively. In CD4＋ PD-1＋ T cells, the frequencies of CD45RA＋CD27＋ T cell, CD45RA-CD27＋ T cell and CD45RA- CD27- T cell subsets were（18.5±8.79）%,（65.0±13.84）% and （15.5±5.12）%,respectively.In CD4＋ PD-1- T cells, the frequencies of the three subsets were （68.25±10.33）%,（27.75±9.04）% and （3.0±1.22）%,respectively. Conclusion The total CD4＋ PD-1- T cells contain mostly naive T cells （CD45RA- CD27-）. However,the central memory T cell （TCM, CD45RA-CD27＋） is the most frequent subset in CD4＋ PD-1＋ T cell population.