Expression of neurotrophic factors by Schwann Cells promotes regeneration of central nervous system

Schwann cells (SCs) are glial cells originally found in the peripheral nervous system. These cells express many neurotrophic factors, which have many implications on neuronal survival and regeneration, and present receptors to some of these factors suggesting autocrine stimulation to SCs survival, proliferation, differentiation and development. Some of these factors are expressed naturally while others need a traumatic situation and/or axonal contact. The secretion of factors has an important function as mediator of neuron-glial signaling. Many expressions of factors are suppressed in SCs of intact nerves but axonal injury promotes increasing of their synthesis and, yet, production of these factors is suppressed during nerve regeneration. The purpose of this article is to review key studies showing that intracerebral SC grafts limit injury-induced tissue loss and promote axonal regeneration and myelination and that this response can be improved by adding neurotrophic factors. Finally, this review will reflect on the prospect of SCs for repairing the nervous system.