Department of Neurology, University of Texas Medical School at Houston, 6431 Fannin Street, Houston, TX 77030, USA.
Department of Neurology, Johns Hopkins University, 600 North Wolfe Street, Baltimore, MD 21287, USA.
Exp Neurol. 2014 Feb;252:57-62. doi: 10.1016/j.expneurol.2013.11.024. Epub 2013 Dec 4.
It is generally accepted that there are two populations of macrophages that respond to neural injuries and successful recruitment of hematogenous macrophages has been shown to help the process of nerve repair in the peripheral nervous system (PNS). Meanwhile, the recruitment of circulating macrophages after central nerve system (CNS) injuries is considered mild and delayed. We compared the recruitment of circulating macrophages in the peripheral nerves and spinal cord after dorsal root ganglionectomies, which induce selective and approximately similar extent of sensory fiber degeneration in PNS and CNS, in bone marrow chimeric mice. Our results showed that circulating macrophages were efficiently recruited in PNS but virtually no recruitment in CNS despite degeneration of peripheral and central sensory projections emanating from the same dorsal root ganglion (DRG) neurons. The mechanisms that prevent recruitment of circulating macrophages in CNS after injury remain poorly elucidated.
人们普遍认为，有两种巨噬细胞群体对神经损伤做出反应，并且已经证明，成功募集血液来源的巨噬细胞有助于外周神经系统 (PNS) 中的神经修复过程。同时，中枢神经系统 (CNS) 损伤后循环巨噬细胞的募集被认为是轻微和延迟的。我们比较了背根神经节切除术（在 PNS 和 CNS 中诱导选择性和大致相似程度的感觉纤维变性）后外周神经和脊髓中循环巨噬细胞的募集情况，在骨髓嵌合小鼠中。我们的结果表明，尽管来自同一背根神经节 (DRG) 神经元的外周和中枢感觉投射发生变性，但循环巨噬细胞在外周神经系统中被有效募集，而在中枢神经系统中几乎没有募集。受伤后防止循环巨噬细胞在中枢神经系统募集的机制仍未得到充分阐明。
