Phenotypic differentiation of aphidicolin-selected human neuroblastoma cultures after long-term exposure to nerve growth factor.

Human neuroblastoma SH-SY5Y (SY5Y) cultures, exposed to murine 7 S nerve growth factor (NGF) for 5 weeks and selected with aphidicolin (Aph) for 1 week, acquire several properties indicative of mature peripheral nerve cells. The mitotic activity of treated cultures decreases prior to Aph selection and ultimately reaches a level approximately 3% that of untreated cultures by Week 4 of treatment. The measured plasma membrane resting potential of the cells increases from -5 mV for untreated cells to -(45-56) mV for NGF/Aph-treated cells. Intracellular stores of monoamines are increased as determined by histochemical staining, and levels of neuron-specific enolase antigen increase as a result of NGF/Aph treatment. The resulting outgrowth of neurites is extensive and large bundles of processes commonly exceed 300 micron in length. NGF/Aph-treated cells acquire a dependence upon NGF for survival; however, with continued administration of NGF, the cultures appear to be capable of surviving indefinitely. Retinoic acid will also promote certain aspects of a differentiated phenotype under similar culture conditions. As judged by these criteria, cells of the SY5Y human neuroblastoma cell line have the potential for phenotypic and irreversible differentiation in vitro and can survive for prolonged periods under these culture conditions.