The intriguing perineurial cells - an updated overview of their origin, structure, functions and implication in pathology.

Abstract

The paper overviews the uniquely intricate and distinct perineurium that envelops nerve fibers in bundles. It consists of perineurial cells (PCs), connective tissue, and blood vessels. The perineurium creates a microenvironment for efficient signal transmission, protects and maintains neuronal structure and function, and facilitates neuronal repair. PCs are a unique type of myofibroblasts essential for maintaining nerve homeostasis. They act as an effective blood-nerve barrier (BNB), protecting against toxins, infections, and mechanical trauma. Despite their crucial function, the origin, ultrastructure, molecular structure, and functional roles of PCs remain a mystery, making them a fascinating area of study.