PD-L1在结肠癌患者CD4^+CD25^(hi)CD127^(low/-)调节性T细胞中的表达及其临床意义

The clinical expression significance of PD-L1 on the CD4^+CD25^(hi)CD127^(low/-) Treg cells in the peripheral blood of colon cancer

目的探讨PD-L1在结肠癌患者外周血CD4+CD25hi CD127low/-Treg细胞上的表达及其与肿瘤病理分期之间的相关性。方法采用流式细胞术分析了47例结肠癌患者外周血中CD4+CD25hi CD127low/-Treg细胞的含量及其PD-L1的表达。结果和健康人比较,结肠癌患者外周血中CD4+CD25hi CD127low/-Treg细胞的含量显著上升,并且PD-L1的表达明显升高。进一步的分析表明,PD-L1的表达和结肠癌的病理分期呈正相关,而术后患者CD4+CD25hi CD127low/-Treg细胞PD-L1的表达则显著下降。结论 CD4+CD25hi CD127low/-Treg细胞数量及PD-L1表达的升高可能导致了免疫抑制的增强,这可能是促进肿瘤免疫逃逸的重要因素。

Objective To investigate the expression of PD-L1 in the CD4^＋ CD25^h1CD^127^low/- Treg cells in the peripheral blood of colon cancer and the correlation with clinical stage. Methods The expression of PD-L1 on CD4^＋ CD25^h1CD^127^low/- Treg cells from 47 samples of the peripheral blood of colon cancer was analyzed by flow eytometry. Results Compared with those from healthy donor,the proportion of CD4^＋ CD25^h1CD^127^low/- Treg ceils and expression of PD-L1 on these cells increased significantly （P〈0.01）. Further analysis showed that expression of PD-L1 increased with the increase of clinical stage of colon cancer （P〈0. 01）, and decreased significantly after postoperation （P〈0.05）. Conclusion Increase of proportion of CD4^＋ CD25^h1CD^127^low/- Treg cells and the expression of PD-L1 may enhance the suppression of antitumor immunity, and thereby promote tumor immunoescape.