Schwann cell precursor: a neural crest cell in disguise?

Schwann cell precursors (SCPs) are multipotent embryonic progenitors covering all developing peripheral nerves. These nerves grow and navigate with unprecedented precision, delivering SCP progenitors to almost all locations in the embryonic body. Within specific developing tissues, SCPs detach from nerves and generate neuroendocrine cells, autonomic neurons, mature Schwann cells, melanocytes and other cell types. These properties of SCPs evoke resemblances between them and their parental population, namely, neural crest cells. Neural crest cells are incredibly multipotent migratory cells that revolutionized the course of evolution in the lineage of early chordate animals. Given this similarity and recent data, it is possible to hypothesize that proto-neural crest cells are similar to SCPs spreading along the nerves. Here, we review the multipotency of SCPs, the signals that govern them, their potential therapeutic value, SCP's embryonic origin and their evolutionary connections. We dedicate this article to the memory of Wilhelm His, the father of the microtome and "Zwischenstrang", currently known as the neural crest.