目的探讨PD-1/PD-L1在MDS母细胞、T淋巴细胞亚群和Treg细胞中的表达及意义。选取88例MDS患者和19例AML患者作为研究对象，对缺铁性贫血和健康骨骼进行研究。骨髓捐赠者用作对照组。流式细胞术检测MDS/AML母细胞、T淋巴细胞亚群、Treg细胞中PD-1/PD-L1的表达量，并检测外周血清中Th1/Th2/Th17相关细胞因子的表达水平。低危MDS组母细胞、T淋巴细胞亚群和Treg细胞中PD-1/PD-L1的表达量低于对照组、中高危MDS组和AML组（均P < 0.01）， Th1/Th17型细胞因子占主导地位。中、高危MDS组和AML组母细胞、T淋巴细胞亚群和Treg细胞中PD-1/PD-L1的表达高于对照组和低危MDS组（均P < 0.01）， Th2型和Treg型(IL-10、TGF-β)细胞因子占主导地位。治疗后，MDS缓解组与对照组母细胞、T淋巴细胞亚群、Treg细胞中PD-1/PD-L1表达差异均无统计学意义（均P>0.05）。 MDS非缓解组母细胞、T淋巴细胞亚群和Treg细胞中PD-1/PD-L1的表达均显着高于缓解组和对照组（均P < 0.01）。 MDS患者中-1/PD-L1、Treg（IL-10、TGF-β）和Th2相关细胞因子的优势以及效应T淋巴细胞的抑制有利于肿瘤细胞增殖和免疫逃逸，可能促进病情进展MDS 疾病。

To investigate the expression and significance of PD-1/PD-L1 in MDS blast cells, T lymphocyte cell subsets and Treg cells.Eighty-eight MDS patients and 19 AML patients were collectd as the study subjects, and Iron deficiency anemia and healthy bone marrow donors were used as control group. The expression of PD-1/PD-L1 in MDS/AML blast cells, T lymphocyte cell subsets and Treg cells was detected by flow cytometry, and the expression level of Th1/Th2/Th17-related cytokines in peripheral serum was detected.The expression of PD-1/PD-L1 in blast cells, T lymphocyte cell subsets and Treg cells in low risk MDS group were lower than that in control group, medium and high risk MDS group and AML group（all P < 0.01）, and Th1/Th17 type cytokines were dominant. The expression of PD-1/PD-L1 in blast cells, T lymphocyte cell subsets and Treg cells of intermediate and high risk MDS group and AML group were higher than that of control group and low risk MDS group (all P < 0.01), and Th2 type and Treg type (IL-10、TGF-β) cytokines were dominant. After treatment, the differences of PD-1/PD-L1 expression were not statisticatly significant in blast cells, T lymphocyte cell subsets and Treg cells between the MDS remission group and the control group (all P >0.05). The expression of PD-1/PD-L1 in blast cells, T lymphocyte cell subsets and Treg cells in MDS non-remission group were significantly higher than that in remission group and control group (all P < 0.01).The high expression of PD-1/PD-L1, dominance of Treg (IL-10、TGF-β) and Th2-related cytokines and inhibition of effector T lymphocyte cells in patients with MDS is conducive to tumor cell proliferation and immune escape, which may promote the progression of MDS disease.