结直肠癌患者外周血CD4^+ CD25^(high)调节性T细胞检测及其表型分析

Analysis of the proportion and phenotype of CD4^+ CD25^(high) regulatory T cells in the peripheral blood of patients with colorectal cancer

目的分析CD4+ CD25high T细胞(Treg)在50例结直肠癌患者外周血中的分布及其表型特征,初步探讨其临床意义。方法采用流式细胞术检测结直肠癌患者及健康人外周血中Treg的比例,探讨其表型特征并分析Treg比例与临床分期间的关系。结果与正常对照(3.1±1.46)%相比,结直肠癌患者外周血中Treg比例明显增加(11.22±5.47)%,二者差异有显著统计学意义(P<0.01);手术后,患者外周血中Treg的比例相比术前显著下降(P<0.01);患者外周血CD4+ CD25high T细胞水平在疾病的临床分期间差异无显著性(P>0.05)。表型分析显示:Treg高表达CD45RO、HLA-Ⅰ、Foxp3分子,较高水平表达OX40、GITR、CD152、CD95、CD95L、B7-H1,较低水平表达CD62L,低表达CD80、CD86、B7-H4分子,基本不表达CD45RA、CD69分子,HLA-DR、CD154的表达水平在个体间差异较大,同时大部分细胞CD127表达阴性。结论结直肠癌患者外周血CD4+ CD25high T细胞水平明显升高,可能与患者肿瘤免疫功能低下密切相关。

Objective To investigate the proportion and the phenotype of CD4＋ CD25high T cell（Treg） in the peripheral blood of patients with colorectal cancer.Methods Flow cytometry was used to evaluate the proportion of Tregs in the peripheral blood of 50 patients with colorectal cancer and 20 healthy people.The changes of the frequency of Tregs in the peripheral blood of 7 patients before and after operation were investigated.The characteristics of phenotype of Tregs.Results Compared with normal control[（3.1±1.46）%],the proportion of Treg in the peripheral blood of patients with colorectal cancer was significantly increased[（11.22±5.47）%,P0.01].After the operation,the frequency of Tregs was decreased（P0.01）.There was no difference in the proportion of Tregs in patients of different stages.The Tregs had high expression of CD45RO combined with low expression of CD45RA,CD69 and CD62L.The costimulatory molecules CD80,CD86 could rarely be detected on the surface of Treg cells,whereas Foxp3 and HLA-Ⅰwere highly expressed.CD152,GITR,OX40,CD95,B7-H1 and CD95L were expressed on the surface of Treg cells at relatively high levels.Some of the Treg cells had variable expression of HLA-DR and CD154.Moreover,most Treg cells were negative for CD127 expression.Conclusion The frequency of Treg cells is increased in the peripheral blood of patients with colorectal carcinoma.These cells may negatively regulate antitumor immune response of patients.