The central nervous system (CNS) contains the two most important organs, the brain and spinal cord, for the orchestration of the mental and physical activities of life. Because of its importance, the human body has evolved barrier systems to protect CNS tissue from the external environment. This barrier is a membrane composed of tightly apposed cells and is selectively permeable to specific molecules by way of membrane transporters. The major barriers in the brain and their corresponding cellular constituents are the blood-brain barrier (BBB) composed of endothelial cells in brain capillaries, the choroid plexus barrier containing ependymal cells, and the meningeal barrier containing arachnoid cells (Lee et al., 2003; Abbott et al., 2006). While previous studies have actively investigated the roles and repair mechanisms of the BBB and choroid plexus barrier under pathological conditions, the meningeal barrier remains an unexplored field. However, recent studies have reported that factors secreted from the meninges are essential for maintaining neuronal integrity under normal conditions, and many cell populations expressing stem cell markers are derived from the meninges after CNS injury (Decimo et al., 2012), suggesting that the meninges could have important roles in maintaining homeostasis and regeneration after CNS injury. Therefore, the meningeal barrier is expected to become a subject of great interest in the field of CNS repair. The meninges are a set of complex membrane structures that cover CNS tissues and are composed of the dura mater, the arachnoid membrane, and the pia mater. The arachnoid membrane consists of arachnoid cells, a type of epithelial cell which forms tight junctions with neighboring cells. Therefore, it functions as a meningeal barrier to separate the CNS from the external environment (Weller, 2005). Meningeal damage is commonly observed with severe CNS injuries induced by falls, vehicle accidents, penetration-like brain trauma, and spinal cord injury. There is significant variability in recovery time for meningeal barrier damage depending on the type of accident and degree of damage. Some patients who show chronic leakage in the meningeal barrier despite medical treatment have a higher possibility of cerebrospinal fluid leakage, meningitis, intracerebral aerocele, and extended secondary damage, which lead to an increased occurrence of permanent disorders and mortality (Leech, 1974). These clinical cases imply that the prompt reconstruction of the impaired meningeal barrier is crucial for reducing additional damage and promoting patient prognosis after CNS injury.