The vertebrate vasculature displays high organotypic specialization, with the structure and function of blood vessels catering to the specific needs of each tissue. A unique feature of the central nervous system (CNS) vasculature is the blood-brain barrier (BBB). The BBB regulates substance influx and efflux to maintain a homeostatic environment for proper brain function. Here, we review the development and cell biology of the BBB, focusing on the cellular and molecular regulation of barrier formation and the maintenance of the BBB through adulthood. We summarize unique features of CNS endothelial cells and highlight recent progress in and general principles of barrier regulation. Finally, we illustrate why a mechanistic understanding of the development and maintenance of the BBB could provide novel therapeutic opportunities for CNS drug delivery.

中文翻译：

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血脑屏障的发育和细胞生物学。

脊椎动物脉管系统表现出高度的器官专业化，血管的结构和功能迎合每个组织的特定需求。中枢神经系统 (CNS) 脉管系统的一个独特特征是血脑屏障 (BBB)。BBB 调节物质流入和流出，以维持正常大脑功能的稳态环境。在这里，我们回顾了 BBB 的发育和细胞生物学，重点关注屏障形成的细胞和分子调控以及 BBB 成年期的维持。我们总结了 CNS 内皮细胞的独特特征，并强调了屏障调节的最新进展和一般原则。最后，我们说明了为什么对 BBB 的发展和维持的机械理解可以为 CNS 药物输送提供新的治疗机会。