NGF-RESPONSE OF EGF-DEPENDENT PROGENITOR CELLS OBTAINED FROM HUMAN SYMPATHETIC-GANGLIA

SIGNALLING molecules are thought to play a significant role in determi ning the fate of neural crest progenitor cells. The human sympathetic chain was identified at 6.5, 7.5, 8.2, 10.2 and 11.4 postconception (P C) weeks demonstrating low affinity nerve growth factor (NGF) receptor s, and was processed for tissue culture. In the presence of epidermal growth factor (EGF), floating spheres of proliferating progenitor cell s were developed in vitro. In the absence of EGF progenitor cells diff erentiated into tyrosine hydroxylase (TH)-immunoreactive neuronal and TH-negative flat cells. NGF treatment significantly increased neurite outgrowth and survival of TH-immunoreactive cells. The multipotent cel ls we isolated differ from previously reported sympathoadrenal progeni tors in that they give rise to TH immunoreactive neurones precociously sensitive to NGF.