In vitro model of microglial deramification: Ramified microglia transform into amoeboid phagocytes following addition of brain cell membranes to microglia-astrocyte cocultures
In vitro model of microglial deramification: Ramified microglia transform into amoeboid phagocytes following addition of brain cell membranes to microglia-astrocyte cocultures
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DOI：
10.1002/jnr.1103
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发表时间：
2001-06-01
影响因子：
4.2
通讯作者：
Raivich, G
中科院分区：
文献类型：
--
作者：
Bohatschek, M;Kloss, CUA;Raivich, G
分支小胶质细胞的形态学变化是脑病理学中的常见特征，并且在存在神经碎片的情况下最终出现小的圆形小胶质细胞衍生的吞噬细胞。在这里，我们探讨了添加脑细胞膜对α M β 2-整合素（CD 11b/CD 18，CR 3）阳性小胶质细胞形态的影响，这些小胶质细胞在融合的星形胶质细胞基质上培养，作为体外脱髓鞘模型。添加脑细胞膜导致小胶质细胞分支的损失，在20-40 μ g/ml时完全转化为小的圆形巨噬细胞。时间进程研究表明，反应迅速，在1-3小时的第一个效果，并在24-48小时完全转化。去除细胞膜和更换培养基导致类似的快速再分支过程。在20 μ g/ml时，来自不同组织的细胞膜的比较显示，对脑的转化作用强，对肾和肝的转化作用较中等，对脾和骨骼肌的转化作用非常弱。荧光标记的脑细胞膜显示摄取几乎所有圆形的巨噬细胞，胶质细胞酸性蛋白（GFAP）阳性星形胶质细胞的亚群，但不是由分枝的小胶质细胞。惰性氟珠的吞噬作用并没有导致转化为巨噬细胞，但它们的吞噬作用受到脑细胞膜的抑制，这表明了一种饱和的摄取机制。总之，脑细胞膜的添加及其吞噬作用导致衍生物的快速和可逆损失。来自不同组织的转化活性的差异和来自吞噬的荧光珠的作用的缺乏表明，然而，在细胞碎片的吞噬作用之后需要第二刺激。(C)2001 Wiley-Liss，Inc.
Changes in the morphology of ramified microglia are a common feature in brain pathology and culminate in the appearance of small, rounded, microglia-derived phagocytes in the presence of neural debris. Here, we explored the effect of adding brain cell membranes on the morphology of alphaM beta2-integrin (CD11b/CD18, CR3) positive microglia cultured on a confluent astrocyte substrate as an in vitro model of deramification. Addition of brain membranes led to a loss of microglial ramification, with full transformation to small, rounded, macrophages at 20-40 mug/ml. Time course studies showed a rapid response, with first effects at 1-3 hours, and full transformation at 24-48 hours. Removal of cell membranes and exchange of the culture medium led to a similarly rapid process of reramification. Comparison of cell membranes from different tissues at 20 mug/ml showed strong transforming effect for the brain, more moderate for kidney and liver, and very weak for spleen and skeletal muscle. Fluorescent labeling of brain membranes revealed uptake by almost all rounded macrophages, by a subpopulation of glial fibrillary acidic protein (GFAP)positive astrocytes, but not by ramified microglia. Phagocytosis of inert fluorobeads did not lead to a transformation into macrophages but their phagocytosis was inhibited by brain membranes, pointing to a saturable uptake mechanism. in summary, addition of brain cell membranes and their phagocytosis leads to a rapid and reversible loss of ramification. The differences in transforming activity from different tissues and the absence of effect from phagocytosed fluorobeads suggest, however, the need for a second stimulus following the phagocytosis of cell debris. (C) 2001 Wiley-Liss, Inc.