García-Verdugo J M, Doetsch F, Wichterle H, Lim D A, Alvarez-Buylla A
University of Valencia, Spain.
J Neurobiol. 1998 Aug;36(2):234-48. doi: 10.1002/(sici)1097-4695(199808)36:2<234::aid-neu10>3.0.co;2-e.
Neural stem cells are maintained in the subventricular zone (SVZ) of the adult mammalian brain. Here, we review the cellular organization of this germinal layer and propose lineage relationships of the three main cell types found in this area. The majority of cells in the adult SVZ are migrating neuroblasts (type A cells) that continue to proliferate. These cells form an extensive network of tangentially oriented pathways throughout the lateral wall of the lateral ventricle. Type A cells move long distances through this network at high speeds by means of chain migration. Cells in the SVZ network enter the rostral migratory stream (RMS) and migrate anteriorly into the olfactory bulb, where they differentiate into interneurons. The chains of type A cells are ensheathed by slowly proliferating astrocytes (type B cells), the second most common cell type in this germinal layer. The most actively proliferating cells in the SVZ, type C, form small clusters dispersed throughout the network. These foci of proliferating type C cells are in close proximity to chains of type A cells. We discuss possible lineage relationships among these cells and hypothesize which are the neural stem cells in the adult SVZ. In addition, we suggest that interactions between type A, B, and C cells may regulate proliferation and initial differentiation within this germinal layer.
神经干细胞存在于成年哺乳动物大脑的脑室下区（SVZ）。在此，我们综述了这个生发层的细胞组织，并提出了该区域发现的三种主要细胞类型的谱系关系。成年SVZ中的大多数细胞是正在迁移的神经母细胞（A型细胞），它们会持续增殖。这些细胞在整个侧脑室的侧壁形成了一个广泛的切向定向通路网络。A型细胞通过链式迁移在这个网络中高速远距离移动。SVZ网络中的细胞进入吻侧迁移流（RMS），并向前迁移到嗅球，在那里它们分化为中间神经元。A型细胞链被缓慢增殖的星形胶质细胞（B型细胞）包裹，B型细胞是这个生发层中第二常见的细胞类型。SVZ中增殖最活跃的细胞，即C型细胞，形成分散在整个网络中的小簇。这些增殖的C型细胞灶紧邻A型细胞链。我们讨论了这些细胞之间可能的谱系关系，并推测成年SVZ中的神经干细胞是哪些。此外，我们认为A型、B型和C型细胞之间的相互作用可能调节这个生发层内的增殖和初始分化。
