摘要目的获得慢性粒细胞白血病人原代干祖细胞模型,旨在研究慢粒白血病病理发生中信号传导的分子机制.方法转导b3a2 bcr/abl cDNA 到正常人CD34+细胞中构建人原代慢性粒细胞性白血病模型.采用细胞免疫组化测定了p210BCR/ABL在CD34+细胞中的表达;细胞粘附、迁移实验进行模型鉴定;FACS法测定了p210BCR/ABL转导及对照CD34+细胞p27kip和MDR-1 Pgp的表达.结果相对于对照的CD34+细胞,转导了bcr/abl的CD34+细胞对纤粘连蛋白(fibronectin, FN)的粘附性下降;而在FN上的迁移能力增强;在低浓度细胞因子或血清条件下表现为凋亡延迟;细胞的粒系克隆形成单位数量明显增多, 这一模型再现了原代慢粒白血病的异常表型特征,并以此模型发现p210BCR/ABL转染CD34+细胞上调了p27Kip水平并可诱导MDR-1 Pgp异常表达.结论该模型适用于慢粒病理发生中的信号分子传导及分子调控研究,提示了慢粒耐药的分子机制.

abstractsAbstract:Objective To develop a primary human hematopoietic stem/progenitor cell model for chronic myeloid leukemia (CML) and study signal transduction and molecular regulation mechanisms in CML. Methods We developed a human model of p210BCR/ABL positive CML by transducing normal human umbilical cord blood CD34+ cells with a retroviral vector containing the b3a2 bcr/abl cDNA. We also examined whether this model recreated the cellular phenotype of CML by assessing cell adhesion, cell migration, cell proliferation and cell survival. Results We found that significantly more myeloid colony forming units grew from p210BCR/ABL expressing cells, adhesion of p210BCR/ABL expressing CD34+ cells to fibronectin was decreased but migration over fibronectin was enhanced compared with mock transduced CD34+ cells. In this model, we showed that the presence of p210BCR/ABL leads to elevated levels of p27kip in p210BCR/ABL expressing CD34+ cells. We also showed that multidrug resistance-1 (MDR-1) Pgp was upregulated in the p210BCR/ABL expressing cells which correlates with the expression of p210BCR/ABL. Conclusion This primary human CML model recreates most of the features of CML and provides a useful tool to study signal transduction and downstream molecular regulation drived by the p210BCR/ABL oncogene in normal CD34+ cells.