Danilov Alexandre I, Gomes-Leal Walace, Ahlenius Henrik, Kokaia Zaal, Carlemalm Eric, Lindvall Olle
Laboratory of Neurogenesis and Cell Therapy, Section of Restorative Neurology, Wallenberg Neuroscience Center, Lund University Hospital, Lund, Sweden.
Glia. 2009 Jan 15;57(2):136-52. doi: 10.1002/glia.20741.
Neural stem cells (NSCs) in the subventricular zone (SVZ) continuously generate olfactory bulb interneurons in the adult rodent brain. Based on their ultrastructural and antigenic properties, NSCs, transient amplifying precursor cells, and neuroblasts (B, C, and A cells, respectively) have been distinguished in mouse SVZ. Here, we aimed to identify these cell types in rat SVZ ultrastructurally and at the light microscopy level, and to determine the antigenic properties of each cell type using gold and fluorescence immunolabeling. We found astrocytes with single cilia (NSCs, correspond to B cells) and neuroblasts (A cells). We also observed mitotic cells, ependymal cells, displaced ependymal cells, and mature astrocytes. In contrast, transient amplifying precursor cells (C cells) were not detected. The NSCs and neuroblasts had epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor alpha (PDGFRalpha) expressed on the ciliary apparatus and were the only cell types incorporating the proliferation marker BrdU. Throughout mitosis, EGFR and PDGFRalpha were associated with the microtubule of the mitotic spindle. Ependymal and displaced ependymal cells also expressed EGFR and PDGFRalpha on their cilia but did not incorporate BrdU. Our findings indicate that the NSCs in adult rat SVZ give rise directly to neuroblasts. During mitosis, the NSCs disassemble the primary cilium and symmetrically distribute EGFR and PDGFRalpha among their progeny.
成年啮齿动物大脑室下区（SVZ）的神经干细胞（NSCs）持续产生嗅球中间神经元。基于其超微结构和抗原特性，在小鼠SVZ中已区分出神经干细胞、短暂扩增前体细胞和成神经细胞（分别为B、C和A细胞）。在此，我们旨在通过超微结构和光学显微镜水平鉴定大鼠SVZ中的这些细胞类型，并使用金标和荧光免疫标记确定每种细胞类型的抗原特性。我们发现了具有单根纤毛的星形胶质细胞（神经干细胞，对应于B细胞）和成神经细胞（A细胞）。我们还观察到有丝分裂细胞、室管膜细胞、移位的室管膜细胞和成熟星形胶质细胞。相比之下，未检测到短暂扩增前体细胞（C细胞）。神经干细胞和成神经细胞在纤毛装置上表达表皮生长因子受体（EGFR）和血小板衍生生长因子受体α（PDGFRα），并且是唯一掺入增殖标记物BrdU的细胞类型。在整个有丝分裂过程中，EGFR和PDGFRα与有丝分裂纺锤体的微管相关联。室管膜细胞和移位的室管膜细胞在其纤毛上也表达EGFR和PDGFRα，但不掺入BrdU。我们的研究结果表明，成年大鼠SVZ中的神经干细胞直接产生成神经细胞。在有丝分裂期间，神经干细胞分解初级纤毛并在其后代中对称分布EGFR和PDGFRα。
