Chick embryonic Schwann cells migrate anodally in small electrical fields

Little is known about the cues that guide migrating neural crest derivatives to their targets. This lack of understanding is especially significant in the case of Schwann cells, which have been transplanted into the central nervous system in an effort to promote axonal myelination after injury or disease. We have investigated the response of Schwann cells, cultured from the peripheral nerves of E7/8 chick embryos, to applied electrical fields. We find that they respond by migrating to the anode, and show a significant anodal bias in directionality at 3 mV mm(-1). This is the smallest electrical field that has been shown to affect cellular movement or growth in culture, and the anodal direction is surprising given the known cathodal responses of neural crest cells. The effective fields are considerably smaller than endogenous electrical fields that have been measured in embryonic tissues.