Meningeal Immunity: Anatomy, Function, and Neonatal Unique Features

The central nervous system (CNS) is responsible for controlling the entire body's functions and actions. The meninges, long seen as physical protection of the CNS, have been recently studied from a completely different perspective, given their unique location and structural composition, as well as the functional features of the vast immune cell repertoire that they comprise. Over the past decade, research has demonstrated the key roles of meningeal immunity in the CNS, either in steady state or pathological conditions. In this review, we provide an overview of meningeal immunity, including its anatomical structure, immune cell composition, and functional dynamics under normal physiological conditions. Moreover, we discuss recent evidence on the involvement of meningeal immunity in neuroinflammation, particularly in the context of infection. Finally, we provide insights into a relatively understudied area: neonatal meninges and their unique immunological features.