R440 – Generation of Neuron-Like Cells in Spiral Ganglion Cultures

ProblemDevelopment of the auditory nerve is dependent on neurotrophic factors. Neurotrophins BDNF and NT-3 are critical in the later stages of development. More recently, a substance secreted by the early inner ear, otocyst-derived factor (ODF), was shown to stimulate development of primitive auditory neurons at the earliest stages. We hypothesized that this powerful neurotrophic substance might be capable of regenerating auditory neurons in the mature animal.MethodsCultured neurons and whole explants from neonatal mouse spiral ganglia were incubated with either BDNF or supernatant from an ODF-secreting cell line.ResultsExposure to ODF resulted in large numbers of cells which stained with neuronal markers, and had neuronal morphology. Though they appeared somewhat different from the native spiral ganglion neurons seen in BDNF-treated cultures, they were present in vastly greater numbers, and appeared to arise from within the proliferating, migrating glial cell populations growing along with the neurons. T...