电离辐射对人造血干细胞CD34+的损伤作用

The damage effect of ionizing radiation on CD34+ of artificial blood stem cells

目的研究不同剂量电离辐射对人造血干细胞CD34+的损害及其机制。方法采集健康人脐带血,分离培养得到CD34+造血干细胞,分为对照组和辐射组。分别用1、2、5 Gy的X线对辐射组细胞进行照射后继续培养24 h后进行对比,检测细胞增殖活性,测定各组内ROS水平并定量测定各组细胞内caspase-3和Nrf-2水平。结果用1、2、5 Gy的电离辐射对CD34+造血干细胞进行照射后,细胞活性降低,ROS释放量增高,细胞内caspase-3、Nrf-2蛋白相对表达量升高,且这种作用与电离辐射剂量相关。结论电离辐射可诱导CD34+造血干细胞损伤,损伤作用很可能与细胞凋亡和氧化应激作用相关。

Objective To investigate the injury effect of different intensity of ionizing radiations on hematopoietic progenitor cells.Methods The CD34＋ hematopoietic progenitor cells were isolated from the cord blood collected from healthy pregnants in the People＇s Hospital of Shaanxi Province.Then the cells were divided into the control group and the radiation group,and the cells of the radiation group were exposed under X-ray irradiations on 1,2,5Gy for 24 h respectively.Cell proliferation activity was detected.The generation of reactive oxygen species（ROS） was evaluated.The caspase-3 and Nrf-2protein levels were also studied.Results With 1,2,5 Gy of ionizing radiation irradiated on CD34＋ hematopoietic stem cells,the cell activity decreased,the release of ROS increased,and the relative expression quantity of caspase-3,Nrf-2 protein in the cell rises,and all the change is associated with the ionizing radiation dose.Conclusion Radiation effects injury HPCsCD34＋,and the effects of the damage is likely related to cell apoptosis and the oxidative stress.