Department of Pathology, CHU Amiens, Amiens, France.
J Neurosci Res. 2010 Jul;88(9):1890-7. doi: 10.1002/jnr.22362.
For several years, a new population of microglia derived from bone marrow has been described in multiple settings such as infection, trauma, and neurodegenerative disease. The aim of this study was to investigate the migration of bone marrow-derived cells to the brain parenchyma after stress exposure. Stress exposure was performed in mice that had received bone marrow transplantation from GFP mice, allowing identification of blood-derived elements within the brain. Electric foot-shock exposure was chosen because of its ability to serve as fundamental and physical stress in mice. Bone marrow-derived GFP(+) cells migrated to the ventral part of the hippocampus and acquired a ramified microglia-like morphology. Microglia marker Iba1 was expressed by 100% of the ramified cells, whereas ramified cells were negative for the astrocyte marker GFAP. Compared with the case in the control group, ramified cells significantly increased after chronic exposure to stress (5 days). One month after 5 days of stress exposure, ramified cells significantly decreased in ventral hippocampus compared with the group examined immediately after the last stress exposure. We report for the first time the migration of bone marrow-derived cells to the ventral hippocampus after stress exposure. These cells have the characteristics of microglia. Mechanisms responsible for this migration and their roles in the brain remain to be determined.
几年来，在感染、创伤和神经退行性疾病等多种情况下，人们已经描述了一种源自骨髓的新的小胶质细胞群体。本研究旨在探讨应激暴露后骨髓源性细胞向脑实质的迁移。在接受 GFP 小鼠骨髓移植的小鼠中进行应激暴露，允许在脑内识别血液来源的成分。选择电足底电击暴露是因为它能够作为小鼠的基本和物理应激。骨髓源性 GFP(+)细胞迁移到海马腹侧部分，并获得分支状的小胶质细胞样形态。100%的分支状细胞表达小胶质细胞标志物 Iba1，而分支状细胞对星形胶质细胞标志物 GFAP 呈阴性。与对照组相比，慢性应激（5 天）后分支状细胞明显增加。应激暴露 5 天后 1 个月，与最后一次应激暴露后立即检查的组相比，腹侧海马中的分支状细胞明显减少。我们首次报道了应激暴露后骨髓源性细胞向海马腹侧的迁移。这些细胞具有小胶质细胞的特征。负责这种迁移的机制及其在大脑中的作用仍有待确定。
