Cellular mechanisms of perivascular fibroblast development and dependence on PDGF signaling

项目摘要 血管周围空间（PVS）是围绕中枢神经系统血管的充满液体的空间， 被认为在维持大脑健康方面具有重要作用，并且是各种 血管周围细胞类型。特别感兴趣的细胞类型是血管周围成纤维细胞（PVF），其在血管周围成纤维细胞（PVF）中表达差。 其特征在于，其功能在很大程度上是未知的。已知PVF位于血管外， 在成年小鼠中枢神经系统中，中至大直径血管的平滑肌层， 主要通过表达胶原蛋白-1和血小板衍生生长因子受体（PDGFR）a鉴定， PDGFR b.然而，几乎没有什么是已知的发育起源，或细胞和分子 对PVF的发展至关重要。初步数据表明PVF来自于一群细胞 并在出生后的发育过程中逐渐填充大脑PVS，但这还没有被证实。 进一步调查。这些知识上的差距是开发新工具来调查作用的主要障碍 PVF在大脑内环境稳定和疾病中的作用。本提案的目的是调查发展中国家的 起源，细胞动力学和分子信号机制参与PVF的发展。在目标1中，我将 使用标记PVF的转基因小鼠系、光学组织清除、离体成像和 多色谱系追踪报告基因，以研究PVF发育的细胞起源和动力学。在Aim中 2、我将使用脑池内脑脊液示踪剂测定，以确定时间之间的关系， PVF发展和PVS功能。最后，在目标3中，我将研究PDGF信号传导作为一种潜在的机制 控制PVF的发展。总之，该项目将是第一个充分描述PVF开发如何 是否发生以及是否涉及PDGF信号传导。

PROJECT SUMMARY Perivascular spaces (PVSs) are fluid-filled spaces surrounding vessels of the central nervous system, are thought to have important roles in maintenance of brain health, and are a unique niche for a variety of perivascular cell types. A cell type of particular interest is perivascular fibroblasts (PVFs) which are poorly characterized, and their functions are largely unknown. PVFs are known to reside on the outside the vascular smooth muscle layer of medium-to large-diameter vessels in the adult mouse central nervous system, and are primarily identified by expression of Collagen-1 and Platelet-derived growth factor receptor (PDGFR)a and PDGFRb. However, nearly nothing is known about the developmental origins, or the cellular and molecular mechanisms important for PVF development. Preliminary data suggests PVFs emerge from a population of cells in the meninges and gradually populate brain PVSs during postnatal development, but this has not yet been investigated further. These gap in knowledge is a major barrier to developing novel tools to investigate the role of PVFs in brain homeostasis and disease. The objective of this proposal is to investigate the developmental origins, cellular dynamics, and molecular signaling mechanisms involved in PVF development. In Aim 1, I will use a combination of transgenic mouse lines that label PVFs, optical tissue clearing, ex vivo imaging, and a multi-color lineage tracing reporter to investigate the cellular origins and dynamics of developing PVFs. In Aim 2, I will use intracisternal cerebrospinal fluid tracer assays to determine the relationship between the timing of PVF development and PVS function. Finally, in Aim 3 I will investigate PDGF signaling as a potential mechanism controlling PVF development. Together, this project will be the first to fully characterize how PVF development occurs and whether or not PDGF signaling is involved.