Tang Ren-Xian, Ding Shuang, Xu Kai-Lin, Jia Lu, Yan Zhi-Ling, Chen Chong, Zeng Ling-Yu
Department of Pathogenic Biology, Xuzhou Medical College, Xuzhou 221002, Jiangsu Province, China.
Zhongguo Shi Yan Xue Ye Xue Za Zhi. 2010 Dec;18(6):1579-84.
The aim of study was to investigate the injury of bone marrow microenvironment after γ ray irradiation conditioning in mouse allogeneic hematopoietic stem cell transplantation (allo-HSCT). The mononuclear cells collected from mice bone marrow for culture in vitro, were identified by flow cytometry with double staining when cultured for 5 - 7 days. Mice were separated randomly into 4 groups, namely, the control group, irradiation group, endothelial progenitor cell (EPC) transplantation group and irradiation combined EPC transplantation group. Peripheral blood was collected to assay the circulating white blood cells. The histological, electron microscopic and immunofluorescence analyses of bone marrow were performed in the same time, furthermore the distribution of labeled EPC was determined. The results showed that EPC were identified as CD45(low/-)CD133(+)CD31(+), double positive of Dil-Ac-LDL and FITC-UEA-1. The bone marrow microenvironment injury of recipient mice was shown in the irradiation group in which the number of WBC began to decrease after conditioning, and the mice were all died at 8 days (p < 0.05). The intramedullary hemorrhage could be detected by light microscopy at 3 days after irradiation, when the destruction of connection between endothelial cell and the basement membrane was observed by TEM. There were CFSE labeled cells in bone marrow in irradiation combined EPC transplantation group at 18 hours after transplanted cultured EPC in vitro, the number of CFSE(+) cells was 58-folds of EPC transplantation group (p < 0.05). It is concluded that the irradiation can cause the severe endothelium injury that drives extrinsic EPC homing to the injured bone marrow microenvironment.
本研究旨在探讨γ射线照射预处理对小鼠异基因造血干细胞移植（allo-HSCT）后骨髓微环境的损伤。从小鼠骨髓中采集单个核细胞进行体外培养，培养5 - 7天后通过双色流式细胞术进行鉴定。将小鼠随机分为4组，即对照组、照射组、内皮祖细胞（EPC）移植组和照射联合EPC移植组。采集外周血检测循环白细胞。同时对骨髓进行组织学、电子显微镜和免疫荧光分析，并确定标记EPC的分布。结果显示，EPC被鉴定为CD45（低/ -）CD133（+）CD31（+），Dil-Ac-LDL和FITC-UEA-1双阳性。照射组受体小鼠出现骨髓微环境损伤，预处理后白细胞数量开始下降，小鼠均在8天死亡（p < 0.05）。照射后3天通过光学显微镜可检测到髓内出血，透射电镜观察到内皮细胞与基底膜连接破坏。体外培养的EPC移植后18小时，照射联合EPC移植组骨髓中有CFSE标记细胞，CFSE（+）细胞数量是EPC移植组的58倍（p < 0.05）。结论是，照射可导致严重的内皮损伤，促使外源性EPC归巢至受损的骨髓微环境。
