Wilms tumor gene(WT1)expression in leukemic and normal hematopoietic stem cells.

由于Wilms肿瘤基因（WT1）在所有白血病患者的骨髓和血液标本中均有高表达，因此利用RT-PCR方法定量该基因的表达，可以估计最小残留白血病（MRD）。正常骨髓细胞CD34片段中WT1基因的低水平表达可能导致WT1检测MRD的敏感性降低。在同种异体骨髓移植环境中，对不表达WT1基因的淋巴瘤患者骨髓细胞的CD34分数和WT1水平进行监测。结果，正常CD34部分和WT1基因表达水平同时来源于该部分的百分比下降到不足十分之一。另一方面，复发时白血病细胞中WT1基因表达增加。因此，该MRD检测系统对于骨髓移植治疗的白血病患者早期分子复发的诊断是非常有用的。

As Wilms' tumor gene (WT1) is highly expressed in bone marrow and blood specimens in all patients with leukemia, minimal residual leukemia (MRD) can be estimated by the quanlitation of the gene expression with RT-PCR method.Low level expression of WT1 gene in CD34 fraction of normal bone marrow cells may result in reducing the sensitivity of the detection of MRD by WT1 assay.In allogeneic bone marrow transplantation setting, CD34 fraction and WT1 levels of the bone marrow cells were monitored in patients with lymphoma who did not expressed WT1 gene.As a result, the percentage of the normal CD34 fraction and WT1 gene expression level derived from the fraction concurrently decreased to less than one tenth.On the other hand, WT1 gene expression in leukemic cells is increased in relapse.Therefore, this MRD detection system is very useful for the diagnosis of early molecular relapse in patients with leukemia who were treated with bone marrow transplantation.