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背景骨髓间充质干细胞(MSCs)是存在于骨髓中的非造血类干细胞,具有自我更新及多向分化潜能。在大鼠脑外伤模型中的迁移能力已得到证实,而其对于脑胶质瘤的趋向性的研究尚处于初期。本实验通过将标记的MSCs移植到大鼠脑胶质瘤模型体内,观察它的迁移情况。方法采用全骨髓细胞培养法,利用MSCs的贴壁生长及可在体外长期培养的特性,获取纯化的MSCs。采用流式细胞术鉴定其表面抗原及细胞周期。在处于对数生长期的MSCs培养皿中加入BrdUrd(终浓度10μg/mL),培养24 ~48 h后进行移植。采用立体定向技术建立大鼠脑胶质瘤模型,3 d后移植标记好的MSCs:在大脑半球组,BrdUrd标记的MSCs被注入大鼠脑胶质瘤模型肿瘤对侧大脑;在颈内动脉组,BrdUrd标记的MSCs被注入大鼠脑胶质瘤模型肿瘤同侧的颈内动脉。分别以BrdUrd标记的3T3细胞作为对照组。2周后,处死大鼠取脑组织制作病理切片,进行抗BrdUrd免疫组化及免疫荧光染色,观察MSCs的迁移情况。结果全骨髓培养法获得了纯化的MSCs。移植到脑组织及颈内动脉的BrdUrd标记的MSCs表现出了明显的向脑胶质瘤迁移的特性。在大脑半球组,MSCs主要集中在肿瘤与正常脑组织的交界部位,在瘤内只有少量分布。在颈内动脉组,MSCs主要分布于肿瘤内部,在肿瘤与正常脑组织的交界位置有少量分布。结论 MSCs具有明显的向脑胶质瘤迁移的特性,同时亦可通过血脑屏障,有可能成为胶质瘤基因治疗的理想载体。
Background Bone marrow mesenchymal stem cells (MSCs) are non-hematopoietic stem cells that exist in the bone marrow and have the potential of self-renewal and multi-directional differentiation. Migration in rat brain trauma models has been demonstrated, and its trend toward gliomas is still in its infancy. In this experiment, MSCs were labeled into rat glioma models and their migration was observed. METHODS: Whole bone marrow cell culture was used to obtain purified MSCs using adherent growth of MSCs and long-term culture in vitro. Flow cytometry was used to identify the surface antigens and cell cycle. BrdUrd (final concentration 10μg / mL) was added to MSCs culture dish in logarithmic growth phase and then cultured for 24-48 h before transplantation. The model of rat glioma was established by stereotactic technique. After 3 days, labeled MSCs were transplanted. BrdUrd-labeled MSCs were injected into the contralateral brain of rat glioma model in the hemisphere. In the carotid artery , BrdUrd labeled MSCs were injected into the ipsilateral internal carotid artery of the rat glioma model tumor. BrdUrd-labeled 3T3 cells were used as the control group. Two weeks later, the rats were sacrificed and the brain tissue was taken for pathological examination. Anti-BrdUrd immunohistochemistry and immunofluorescence staining were performed to observe the migration of MSCs. Results The purified MSCs were obtained by whole bone marrow culture. BrdUrd-labeled MSCs transplanted into brain and internal carotid arteries showed marked migration characteristics to gliomas. In the cerebral hemisphere group, MSCs were mainly located at the junction of tumor and normal brain tissue with only a small amount of distribution in the tumor. In the internal carotid artery group, MSCs were mainly distributed in the tumor, with a small amount of distribution at the junction of tumor and normal brain tissue. Conclusion MSCs have the obvious characteristics of migrating to gliomas and crossing the blood-brain barrier at the same time, which may be an ideal carrier for gene therapy of glioma.