急性髓系白血病患者外周血表达髓系抑制细胞的临床研究

Expression of myeloid-derived suppressor cells from peripheral blood in the different stages of AML patients

目的:检测急性髓系白血病(AML)患者不同阶段外周血髓系抑制细胞(MDSCs)的表达量,并探讨其与肿瘤相关巨噬细胞(TAM,CD206+)、调节性T细胞(Tregs,CD4+CD25+)的关系。方法:采用流式细胞术检测AML患者30例初诊未治及完全缓解(CR)后外周血表型为CD33+/CD11b+/HLA-DR-/lin-的MDSCs比例,同时检测TAM及Tregs表达水平,并以健康体检者30例作为对照,检测以上指标的变化。结果:1AML患者初诊未治期外周血MDSCs高度表达,显著高于对照者[(5.83±1.66)%∶(0.63±0.31)%,P<0.05],经化疗达CR后其数值显著下降,均值为(1.03±0.20)%,CR前、后比较差异有统计学意义(P=0.03);2AML患者初诊未治期外周血表达CD206+的TAM高于对照者[(5.32±1.55)%∶(1.69±0.44)%,P=0.15],经治疗达CR后明显回落;3AML患者初诊未治期外周血表达CD4+CD25+的Tregs明显高于治疗后及对照者[(6.75±0.68)%∶(2.21±0.45)%∶(1.98±0.65)%),P<0.01]。结论:MDSCs在AML不同阶段呈规律性表达,与TAM及Tregs表达趋势一致,提示在AML发生、发展过程中MDSCs可能参与了白血病细胞的免疫耐受及肿瘤逃逸机制。

Objective：To investigate the expression of myeloid-derived suppressor cells（MDSCs）in peripheral blood of acute myeloid leukemia（AML）patients at different stages,and to evaluate their correlation with CD4＋CD25＋regulatory T cells（Tregs）and tumor-associated macrophage（TAM,CD206＋）.Method：We used flow cytometry method to detect the MDSCs with phenotype as CD33＋/CD11b＋/HLA-DR-/lin-in 30 newly diagnosed pre-therapy and complete remission（CR）stage AML patients,and we detected the expression of Tregs（CD4＋CD25＋）and TAM（CD206＋）.Thirty healthy people were enrolled as control group.Result：1In newly diagnosed pre-therapy patients with AML,the expression of MDSCs was significantly higher than that of healthy people[（5.83±1.66）% vs（0.63±0.31）%,P〈0.05],and decreased significantly after CR with chemotherapy,with the mean value of（1.03±0.20）%,the difference between the pre-therapy and CR stage had statistical significance（P=0.03）.2In newly diagnosed pre-therapy patients with AML,the expression of CD206＋was higher than that of healthy persons[（5.32±1.55）% vs（1.69±0.44）%,P=0.15],and it decreased after CR.3In newly diagnosed pre-therapy patients with AML,the expression of CD4＋CD25＋Tregs was significantly higher than those of CR stage and healthy people[（6.75±0.68）% vs（2.21±0.45）% vs（1.98± 0.65）%,P〈0.01].Conclusion：The expression of MDSCs in AML patients is higher than that of healthy people and is significantly decreased after CR,with a regulary change of TAM and Tregs,suggesting that MDSCs may be involved in the immune tolerance and tumor escape mechanisms of leukemia cells in AML patients.