急性髓系白血病治疗前后白血病干细胞的变化

Changes of Leukemia Stem Cells in Acute Myeloid Leukemia before and after Treatment

目的:观察急性髓系白血病(acute myeloid leukemia,AML)中是否存在白血病干细胞(leukemia stem cells,LSC)及其与白血病细胞在流式细胞图中的相对位置,分析白血病微小残留病(minimal residual diseases,MRD)与LSC水平的相关性,探讨白血病化疗过程中LSC的变化与白血病的疗效及预后的关系。方法:采集50例AML(除外M3)患者骨髓标本85份,其中初治患者标本50份,未缓解AML患者标本7份,完全缓解期AML患者标本28份。所有标本均应用流式细胞术检测免疫表型为CD34^+/CD38^-/CD123^+的LSC,同时对初治患者标本行白血病肿瘤细胞免疫表型检测,对非初治患者标本根据初治免疫表型获得的白血病相关免疫表型(leukemia associated immune phenotype,LAIP)进行白血病微小残留病检测。结果:AML中存在CD34^+/CD38^-/CD123^+的LSC,其与白血病细胞在流式细胞图中的相对位置是一致的。化疗后骨髓完全缓解组LSC含量(0.096‰)比初治AML组LSC含量(0.541‰)明显降低,两组比较,其差异具有显著性(P<0.01);初治AML组与化疗后未缓解组之间的LSC含量的差异无显著性(P>0.05)。对同时进行LSC和MRD检测的28例完全缓解AML患者中的LSC含量和MRD水平进行相关性分析发现,2者存在显著正相关性(r=0.680,P<0.01)。结论:AML中确实存在LSC,其与白血病细胞在流式细胞图中的相对位置是一致的,推测其形态上同白血病细胞相似,大小相仿,具有弱表达CD45等一些白血病细胞的特征。化疗后LSC的比例较化疗前下降,在白血病治疗过程中检测和追踪LSC的变化,联合微小残留病(MRD)的检测技术,可以更好地判断白血病的疗效和预后。

Objective： To investigate the presence of leukemia stem cells（ LSC） in acute myeloid leukemia（ AML）and find out the relative position of leukemia cells in the figures of flow cytometry,and to analyze the relationship between minimal residual diseases（ MRD） and the level of LSC,so as to explore the correlation of LSC changes with the curative effect and the prognosis during chemical therapy.Methods： A total of 85 samples were collected from 50 AML（ except M3） patients,including 50 samples from the newly diagnosed patients,7 samples of AML patients with non-remission and 28 samples of AML patients with complete remission.All samples were used for detection of LSC from immune phenotype of CD34^＋/CD38^-/CD123^＋ by flow cytometry.The detection of immune phenotypic of leukemia cells was performed in the newly diagnosed patients.The detection of leukemia-associated immune phenotypes（ LAIP） was implemented in the non-newly diagnosed patients.Results： The LSC was identified in the CD34^＋/CD38^-/CD123^＋ in AML and consistent with the relative position of the leukemia cell in flow cytometry figures.Statistical analysis showed significant difference in LSC content between the newly diagnosed AML group and the post-chemotherapy complete remission group（ P〈0.01）,but did not between the newly diagnosed AML group and the post-chemotherapy non-remission group（ P〉0.05）.There was significant positive correlation between the LSC content and MRD level in 28 AML patients with complete remission（ r = 0.680,P〈0.01）.Conclusion： LSC exist in AML and the relative position are consistent with the leukemia cells in flow cytometry figures,the size characteristics and weak expression of CD45 are also similar to leukemia cells.The proportion of LSC decreases after chemotherapy.Detecting and tracking the LSC changes in bone marrow and combination with detecting minimal resident disease（ MRD） may contribute to evaluate the theraputic efficacy and prognosis of leukemia patients.