【作者】 姜玉峰；

【导师】 慕晓玲；

【作者基本信息】 石河子大学 ， 人体解剖学与组织胚胎学， 2005， 硕士

【摘要】 研究目的:用低剂量NaAsO₂长期诱导人骨髓间充质干细胞（mesenchymal stem cells,MSCs）,获得抗砷细胞,探讨机体抗砷机制。 研究方法:通过比较不同年龄人骨髓MSCs细胞倍增时间,细胞贴壁率等生物学性状及细胞的砷耐受性,筛选抗砷种子细胞;选取胎儿骨髓MSCs,采用细胞抑制率在5%-10^时的NaAsO₂浓度（1μmol/L）为砷诱导浓度,同时设一组不加砷培养的胎儿骨髓MSCs作为同步对照,用噻唑兰法（MTT）监测细胞抗砷性是否产生;采用氢化物发生—原子荧光方法检测细胞砷含量,二硫代二硝基苯甲酸直接显色法,比较抗砷细胞与同步对照组胞内GSH,GST等砷代谢指标的变化,验证细胞是否获得抗砷性,并初步探讨了细胞产生抗砷能力的机制。 结果:不同年龄人骨髓MSCs在细胞形态、生长特性等方面是相似的,胎儿骨髓MSCs的扩增潜能明显强于成人和老人骨髓MSCs。选择胎儿骨髓MSCs作为抗砷种子细胞,经过18周NaAsO₂诱导后,细胞对急性砷中毒的耐受性明显提高,排砷能力增强,细胞内GSH和GST活性增高。 结论:胎儿骨髓MSCs体外增殖分裂能力最强。人骨髓MSCs在低剂量NaAsO₂长期诱导下,能分化为具有抗砷能力的细胞。更多还原

【Abstract】 Objective : To select the suitable cells ,we explored the difference of biological characteristics among the fetal, adult and old mesenchymal stem cells（MSCs） derived from bone marrow. To obtain stable arsenic-resistance cells, the fetal MSCs were exposed to low-level arsenite for 18 weeks. Methods: Cells from 6 months fetal, adult and old bone marrow were cultured in α-MEM medium to obtain MSCs. The growth curve , the adherent ability and the toxicity of NaAsO₂ were investigated. After 24h cytotoxicity test of the fetal MSCs, we chosed lumol/L NaAsO₂ to be the dose under which the cell death-rate was 5%-10% .The fetal MSCs were exposed to low-level arsenite. MTT was used to detect the survival rate and IC50 of arsenic-exposed cells and the control cells, which can reflect the change of arsenic tolerance. A hydride generation—atomic fluorescence spectrometry method was used to detect arsenic in the arsenic-resistance cells and the control cells. In order to study the mechanism of arsenic-resistance, we also examined the intracellular GSH and GST content in the arsenic-resistance cells and the control cells. Results: The fetal, adult and old MSCs were similar in cell morphology.The proliferation of the MSCs from the fetus was higher than that from the adult and the old . The fetal MSCs were continuously exposed to lumol/L NaAsO₂. Parallel cells were cultured in medium without arsenic provided passage-matched control. After the fetal MSCs were continuously exposed to low level NaAsO₂ for 18 weeks, cells exhibited dramatic resistance to acute arsenite toxicity. Compared to control cells, arsenic-resistance cells showed reduction in arsenic accumulation in cells. The GSH levels and GST activity of arsenic-resistance cells were higher than that of control cells.Clonclusion: The fetal MSCs had a big ability of proliferation. Acquisition of stable arsenic-resistance in MSCs was available by using cell culture and adding low-level arsenic. Our research established a solid basis for further study about the mechanisms of arsenic-resistance in human being.更多还原