Department of Cell and Tissues, Faculty of Veterinary Medicine, Assuit University, Assiut 71526, Egypt.
Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Sohag University, Sohag 82524, Egypt.
Cells. 2022 Aug 27;11(17):2659. doi: 10.3390/cells11172659.
This study was conducted on 16 adult specimens of molly fish () to investigate ependymal cells (ECs) and their role in neurogenesis using ultrastructural examination and immunohistochemistry. The ECs lined the ventral and lateral surfaces of the optic ventricle and their processes extended through the tectal laminae and ended at the surface of the tectum as a subpial end-foot. Two cell types of ECs were identified: cuboidal non-ciliated (5.68 ± 0.84/100 μm) and columnar ciliated (EC3.22 ± 0.71/100 μm). Immunohistochemical analysis revealed two types of GFAP immunoreactive cells: ECs and astrocytes. The ECs showed the expression of IL-1β, APG5, and Nfr2. Moreover, ECs showed immunostaining for myostatin, S100, and SOX9 in their cytoplasmic processes. The proliferative activity of the neighboring stem cells was also distinct. The most interesting finding in this study was the glia-neuron interaction, where the processes of ECs met the progenitor neuronal cells in the ependymal area of the ventricular wall. These cells showed bundles of intermediate filaments in their processes and basal poles and were connected by desmosomes, followed by gap junctions. Many membrane-bounded vesicles could be demonstrated on the surface of the ciliated ECs that contained neurosecretion. The abluminal and lateral cell surfaces of ECs showed pinocytotic activities with many coated vesicles, while their apical cytoplasm contained centrioles. The occurrence of stem cells in close position to the ECs, and the presence of bundles of generating axons in direct contact with these stem cells indicate the role of ECs in neurogenesis. The TEM results revealed the presence of neural stem cells in a close position to the ECs, in addition to the presence of bundles of generating axons in direct contact with these stem cells. The present study indicates the role of ECs in neurogenesis.
本研究对 16 条成年翻车鱼标本进行研究，通过超微结构观察和免疫组织化学方法研究室管膜细胞（EC）及其在神经发生中的作用。EC 排列在视脑室的腹侧和外侧表面，其突起穿过脑桥层并在脑桥表面终末作为软膜足。鉴定出两种 EC 细胞类型：立方无纤毛（5.68 ± 0.84/100 μm）和柱状纤毛（EC3.22 ± 0.71/100 μm）。免疫组织化学分析显示两种类型的 GFAP 免疫反应性细胞：EC 和星形胶质细胞。EC 表达 IL-1β、APG5 和 Nfr2。此外，EC 的细胞质突起显示肌肉抑制素、S100 和 SOX9 的免疫染色。邻近干细胞的增殖活性也明显不同。本研究最有趣的发现是胶质-神经元相互作用，EC 的突起与脑室壁室管膜区的祖细胞神经元细胞相遇。这些细胞在其突起和基底极显示中间丝束，并通过桥粒连接，随后通过缝隙连接。在纤毛 EC 的表面可以显示许多含有神经分泌的膜结合小泡。EC 的基底外侧和侧细胞表面显示具有许多有被小泡的胞饮作用，而其顶质体含有中心粒。靠近 EC 的干细胞的存在，以及与这些干细胞直接接触的生成轴突束的存在，表明 EC 在神经发生中的作用。TEM 结果表明，除了与这些干细胞直接接触的生成轴突束外，EC 附近还存在神经干细胞。本研究表明 EC 在神经发生中的作用。
