Gao Xiang, Enikolopov Grigori, Chen Jinhui
Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, Kentucky 40536-0082, USA.
J Neurotrauma. 2008 Aug;25(8):985-95. doi: 10.1089/neu.2008.0460.
Recently, we have manipulated endogenous neural stem/progenitor cells (NSCs) in situ in the adult mouse to undergo neurogenesis and anatomic circuit re-formation de novo in the neocortex, where it does not normally occur, by using a highly targeted brain injury model. However, how the NSCs respond to injury in the adult mouse brain is poorly understood. While studying the molecular mechanisms that regulate NSC fates after brain injury, it is important to develop a strategy to identify NSCs in niches and isolate them directly from fresh tissue after brain injury. Here we report that we directly isolated NSCs from adult brains after traumatic brain injury by genetically labeling NSCs with EGFP combined with fluorescence-activated cell sorting (FACS) technique without an intervening cell culture and with high concentrations of growth factors. The isolated EGFP-positive cells can self-renew and have the potential to differentiate into both neurons and glia in vitro, confirming that the FACS-sorted EGFP-positive cells are NSCs. This unique approach provides a useful tool to isolate large amounts of endogenous NSCs in situ for identifying the critical molecules that regulate fate decision and neurogenesis in the adult brain after injury.
最近，我们通过使用高度靶向的脑损伤模型，在成年小鼠体内原位操纵内源性神经干细胞/祖细胞（NSCs），使其在新皮质中发生神经发生和从头形成解剖学回路，而新皮质通常不会发生这种情况。然而，人们对成年小鼠脑中的神经干细胞如何对损伤作出反应知之甚少。在研究脑损伤后调节神经干细胞命运的分子机制时，开发一种在脑损伤后直接从新鲜组织中鉴定神经干细胞生态位并分离它们的策略非常重要。在此我们报告，通过用EGFP对神经干细胞进行基因标记并结合荧光激活细胞分选（FACS）技术，我们在创伤性脑损伤后直接从成年大脑中分离出神经干细胞，无需进行中间细胞培养，也无需添加高浓度生长因子。分离出的EGFP阳性细胞能够自我更新，并且在体外具有分化为神经元和神经胶质细胞的潜力，这证实了通过FACS分选的EGFP阳性细胞是神经干细胞。这种独特的方法为原位分离大量内源性神经干细胞提供了一个有用的工具，用于鉴定调节成年脑损伤后命运决定和神经发生的关键分子。
