美国圣路易斯华盛顿大学Jonathan Kipnis等研究人员合作确定硬脑膜与大脑之间的直接联系。这一研究成果于2024年2月7日在线发表在国际学术期刊《自然》上。

研究人员利用转录组数据开发了转基因小鼠，以研究作为蛛网膜屏障通道的特定解剖结构。桥状静脉在穿过蛛网膜屏障时会产生不连续性，形成被称为蛛网膜袖口出口（ACE）点的结构。ACE点所形成的开口允许蛛网膜下腔和硬脑膜之间的液体和分子交换，使脑脊液得以排出，并限制分子从硬脑膜进入蛛网膜下腔。在健康的人类志愿者身上，磁共振成像示踪剂以类似的方式沿着桥静脉进入蛛网膜下腔。

值得注意的是，在神经炎症（如实验性自身免疫性脑脊髓炎）中，ACE点也能进行细胞转运，是免疫细胞从硬脑膜直接进入蛛网膜下腔的途径。总之，这些研究结果表明，ACE点是小鼠和人类神经免疫通信解剖学的关键部分，它将中枢神经系统与硬脑膜及其免疫多样性和废物清除系统联系在一起。

据悉，蛛网膜屏障划定了中枢神经系统和硬脑膜之间的边界。虽然蛛网膜屏障形成了一个分区，但中枢神经系统和硬脑膜之间的交流对于废物清除和免疫监视至关重要。人们对蛛网膜屏障如何平衡分隔与交流还知之甚少。

附：英文原文

Title: Identification of direct connections between the dura and the brain

Author: Smyth, Leon C. D., Xu, Di, Okar, Serhat V., Dykstra, Taitea, Rustenhoven, Justin, Papadopoulos, Zachary, Bhasiin, Kesshni, Kim, Min Woo, Drieu, Antoine, Mamuladze, Tornike, Blackburn, Susan, Gu, Xingxing, Gaitn, Mara I., Nair, Govind, Storck, Steffen E., Du, Siling, White, Michael A., Bayguinov, Peter, Smirnov, Igor, Dikranian, Krikor, Reich, Daniel S., Kipnis, Jonathan

Issue&Volume: 2024-02-07

Abstract: The arachnoid barrier delineates the border between the central nervous system and dura mater. Although the arachnoid barrier creates a partition, communication between the central nervous system and the dura mater is crucial for waste clearance and immune surveillance1,2. How the arachnoid barrier balances separation and communication is poorly understood. Here, using transcriptomic data, we developed transgenic mice to examine specific anatomical structures that function as routes across the arachnoid barrier. Bridging veins create discontinuities where they cross the arachnoid barrier, forming structures that we termed arachnoid cuff exit (ACE) points. The openings that ACE points create allow the exchange of fluids and molecules between the subarachnoid space and the dura, enabling the drainage of cerebrospinal fluid and limited entry of molecules from the dura to the subarachnoid space. In healthy human volunteers, magnetic resonance imaging tracers transit along bridging veins in a similar manner to access the subarachnoid space. Notably, in neuroinflammatory conditions such as experimental autoimmune encephalomyelitis, ACE points also enable cellular trafficking, representing a route for immune cells to directly enter the subarachnoid space from the dura mater. Collectively, our results indicate that ACE points are a critical part of the anatomy of neuroimmune communication in both mice and humans that link the central nervous system with the dura and its immunological diversity and waste clearance systems.

DOI: 10.1038/s41586-023-06993-7

Source: https://www.nature.com/articles/s41586-023-06993-7