Minimal residual leukemia in autologous peripheral blood stem cell transplantation

我们研究了儿童急性淋巴细胞白血病（ALL）和急性髓母细胞白血病（AML）的自体外周血干细胞移植（PBSCT）中的微小残留病（MRD）。MRD可以定义为发生在亚临床水平的疾病，无法通过传统的评估方法检测到。将聚合酶链反应（PCR）应用于免疫球蛋白重链（IgH）基因的高变段或t淋巴细胞受体基因和特异性嵌合体信使RNA的RT-PCR，可以在10^4-10^5个正常骨髓细胞中以1个白血病细胞的水平检测ALL和AML的MRD。采集外周血干细胞（PBSC）的MRD检测对自体外周血干细胞移植的适应症有一定的参考价值。我们在3例ALL和4例AML完全缓解后采集的PBSC中检测到MRD。在AML伴t(8; 21)（q22; q22）的病例中，在PBSC中检测到嵌合RNA。在其他情况下，在PBSC中未检测到MRD。7例急性白血病患者均行自体PBSCT。6例患者移植后完全缓解，无MRD症状。但在1例外周血母细胞中有嵌合RNA的AML患者中，移植后6个月出现骨髓复发。

We investigated minimal residual disease (MRD) in autologous peripheral blood stem cell transplantation (PBSCT) for acute lymphoblastic leukemia (ALL) and acute myeloblastic leukemia (AML) in children. MRD can be defined as disease occurring at a subclinical level and beyond detection by conventional methods of assessment. Application of the polymerase chain reaction (PCR) to the hypervariable segment of the immunoglobulin heavy chain (IgH) gene or T-lymphocyte receptor gene and RT-PCR of specific chimera messenger RNA,allows detection of MRD in ALL and AML at a level of one leukemic cell in 10^4-10^5 normal marrow cells. The detection of MRD of harvested peripheral blood stem cell (PBSC) have a value in the indication of autologous PBSCT.We detected MRD in the harvested PBSC after complete remission for 3 cases of ALL and 4 cases of AML.In a case of AML with t(8 ; 21)(q22 ; q22), chimeric RNA was detected in PBSC.In other cases, MRD was not detected in PBSC.These 7 patients with acute leukemia were performed autologous PBSCT.Six patients have sustained complete remission without sign of MRD after transplantation. But in a case of AML with t(8 ; 21)(q22 ; q22) who has chimeric RNA in her PBSC,bone marrow relapse occurred 6 month after transplantation.