再生障碍性贫血、骨髓增生异常综合征、急性髓系白血病患者CD8＋T细胞亚群的变化及临床意义

摘要本研究检测再生障碍性贫血（AA）、骨髓增生异常综合征（MDS）和急性髓系白血病（AML）患者细胞毒T细胞亚群平衡及其活性的改变，探讨三种疾病造血异常的细胞免疫机制，为临床治疗选择提供实验室依据。采用流式细胞术检测AA组17例、MDS组35例（其中RA19例，RAEB16例）、AML组15例和正常对照组10例的细胞毒性T细胞（Tc1、Tc2）以及部分T细胞亚群比例并进行对比分析。结果表明：与正常对照组相比，AA组、MDS-RA组Tc1、Tc1／Tc2、CD8＋HLA-DR＋、CD3＋CD8＋CD28＋、CD8＋CIM5RO＋显著升高，Tc2无明显统计学差异，CD8＋CD45RA＋显著减低；MDS-RAEB组Tc1、CD3＋CD8＋CD28＋、CD8＋HLA．DR＋比例显著减低，Tc、Tc1／Tc2无明显变化，CD8＋CD45RA＋减低但差异不明显，CD8＋CD45RO＋显著升高；AML组Tcl、CD3＋CD8＋CD28＋、CD8＋CD45RA＋、CD8＋CD45RO＋、CD8＋HLA。DR＋，Tc1／Tc2显著减低，Tc2显著上升。结论：AA、MDS不同阶段、AML患者的细胞免疫状态不同，在AA和MDS早期阶段，Tc1／Tc2的平衡向Tcl偏移，且伴有T细胞亚群活性增加；而在MDS晚期和AML阶段，则向Tc2偏移，T细胞亚群活性减低。前者可能与骨髓造血衰竭密切相关，而后者可能是恶性克隆免疫挑挽的重要机制之一．

Changes and Clinical Significance of CD8+T Cell Subset in Patients with Aplastic Anemia, Myelodysplastic Syndrome and Acute Myeloid Leukemia

This study was purposed to detect the balance and the activity change of cytotoxic T cell subsets in aplastic anemia（AA） patients, myelodysplastic syndrome（MDS） patients and acute myeloid leukemia（AML） patients, and to explore the cellular immune mechanism for abnormal hematopoiesis of the three diseases, so as to provide experiental basis for the choice of clinical treatment. The proportion of the cytotoxic T cells and part of the T-cells subsets in peripheral blood were detected by flow cytometry in 35 cases of MDS, including 19 refractory anemia （MDS-RA）, 16 refractory anemia with excess blasts （MDS-RAEB）, 17 AA, 15 AML patients and 10 normal donors respectively. The results showed that compared with the control group, the percentage of Tcl ,Tcl/Tc2,CD8 ＋ HLA-DR＋ , CD3 ＋ CD8 ＋ CD28 ＋ , CD8 ＋ CD45RO ＋ cells was significantly higher and the percentage of CD8 ＋ CD45RA ＋ was significantly lower in AA and MDS-RA group. There was no difference in the percentage of Tc2 cells between AA/MDS-RA and normal controls; the percentage of CD8 ＋ CD45RO ＋ cells was significantly higher and the percentage of Tcl, CD3 ＋ CD8 ＋ CD28 ＋ , CD8 ＋ I-ILA-DR＋ was significantly lower in MDS-RAEB group, the percentage of CD8 ＊ CD45RA＋ was lower but the difference was not significant, and there was no difference in the percentage of Tc,Tcl/Tc2 cells between MDS-RAEB group and the control group. The percentage of Tc2 cells was significantly higher and the percentage of other parameters was significantly lower in AML group than those of normal controls. It is concluded that the cellular immune statuses in AA, the different stages of MDS and AML are different. In AA and the early stage of MDS, the balance of Tcl/Tc2 shifts to Tcl, and the activation of T-cell subsets increases. In the late stage of MDS and AML, the balance of Tcl/Tc2 shifts to Tc2, the activation of T-ceU subsets decreases. The former may be closely related to bone marrow failure while the latter may be one of the important mechanisms in which the malignant clones escape from immune effect.