Stem Cell Generation of Transport Epithelia for the Brain's Ventricular System

这项提议的目标是研究胎儿神经上皮干细胞如何支持神经发生 和室管膜发育，并确定脑室扩大或脑积水如何影响 室管膜发生和相关的干细胞功能。室管膜细胞呈单层状排列。 脑室壁作为脑脊液(CSF)和间质之间运输的功能单位 流体(ISF)。健康的室管膜使脑脊液循环，有助于清除脑内间质的毒素。 薄壁组织。在妊娠中期，神经上皮细胞产生足够数量的室管膜细胞。 干细胞覆盖整个脑室表面，但在脑积水中，脑室周围干细胞的壁龛是 需要产生更多的室管膜细胞来覆盖扩张的脑室。我们将测试 假设脑室扩张会耗尽干细胞库，并导致对 脑室表面、脑室周围胶质增生症，以及关键的跨室间膜转运/清除功能丧失。 实验旨在记录干细胞和干细胞之间的动态供需关系 他们的子代室管膜细胞，在人类组织和小鼠脑积水模型中。在目标1中，我们将 创建室管膜细胞生成的时空图，并确定 正常胎儿和出生后人室管膜细胞和干细胞数量/组织的分布 脑室周围脑组织。类似的研究将在小鼠身上进行，并补充延时干法 使用宫内电穿孔系统中的iggyBac进行细胞谱系追踪，以追踪干细胞的命运并进行检测 室管膜发生是否导致干细胞退出细胞周期。生成的3D时空地图 室管膜发育将作为评估室管膜发育异常和干细胞巢的工具 脑积水的变化。在目标2中，我们将研究几种脑积水模型，以确定 脑室表面的干细胞巢和室管膜细胞覆盖率受到影响。细胞组织、细胞-细胞 交界处复合体、跨室室管膜血流的改变和脑室表面的清除机制 干细胞动力学将被阐明。生成的数据将使您深入了解 神经上皮干细胞用于脑室表面修复以及干细胞功能缺陷如何 导致与脑积水相关的多种神经病理改变。

The goals of this proposal are to examine how the fetal neuroepithelial stem cells support both neurogenesis and ependymogenesis, and to determine how ventricular enlargement, or hydrocephalus, affects ependymogenesis and associated stem cell functions. Ependymal cells are arranged as a monolayer along the ventricle walls and act as the functional units of transport between the cerebrospinal fluid (CSF) and interstitial fluid (ISF). A healthy ependyma circulates CSF and facilitates the clearance of toxins from the ISF of the brain parenchyma. During mid-gestation, sufficient numbers of ependymal cells are generated from neuroepithelial stem cells to cover the entire ventricle surface, but in hydrocephalus, the periventricular stem cell niche is called upon to generate many more ependymal cells to cover the expanding ventricles. We will test the hypothesis that ventricle expansion exhausts the stem cell pool and results in insufficient coverage of the ventricle surface, periventricular gliosis, and loss of critical transependymal transport/clearance functions. Experiments are designed to document the dynamic supply and demand relationship between stem cells and their progeny ependymal cells, in both human tissue and mouse models of hydrocephalus. In Aim 1, we will create spatiotemporal maps of ependymal cell generation and determine the relationship between the distribution of ependymal cells and stem cell numbers/organization in normal fetal and postnatal human periventricular brain tissue. Similar studies will be performed in mouse, supplemented with time-lapse stem cell lineage tracing using the piggyBac in utero electroporation system, to track stem cell fates and test whether ependymogenesis results in stem cell exit from the cell cycle. The resulting 3D spatiotemporal maps of ependymogenesis will serve as tools for evaluating abnormal ependyma development and stem cell niche changes in hydrocephalus. In Aim 2, we will examine several models of hydrocephalus to determine how the stem cell niche and ependymal cell coverage of the ventricle surface are affected. Cell organization, cell-cell junction complexes, alterations in transependymal flow and clearance mechanisms at the ventricle surface and stem cell dynamics will be elucidated. Data generated will provide insight into the regenerative potential of neuroepithelial stem cells for repair of the ventricle surface and how deficits in stem cell functions may contribute to the multiple neurologic pathologies associated with hydrocephalus.