vEM reveals the cellular composition of the Blood Nerve Barrier

The blood barriers of the nervous system are essential for protecting neural tissues and maintaining homeostasis. While the blood-brain barrier (BBB) of the central nervous system (CNS) is well characterized, comprising a monolayer of endothelial cells supported by nearly complete pericyte and astrocyte coverage, there is a lack of comparable understanding in the peripheral nervous system (PNS). 

In the CNS, the microenvironment of the BBB is critical for its barrier properties However, the structure and regulation of the blood-nerve barrier (BNB) in the PNS remain poorly understood. The BNB plays a crucial role in PNS function, yet its vascular component (EndoVs) and its cellular composition have not been described to date, despite the importance of the BNB for PNS function, with disruption associated with disorders such as diabetes and neuropathies.