Generation of inner ear hair cell immunophenotypes from neurospheres obtained from fetal rat central nervous system in vitro.

Neural stem cells are suggested to possess a highly plastic ability to differentiate into several specific cell types, not only neuronal lineages but also other germ layer tissue-specific cell lineages. To examine whether hair cell immunophenotypes could be derived from the central nervous system (CNS), we established cell cultures from embryonic day 16.5 fetal rat brain tissues, and analyzed changes in immunohistochemical features of the CNS cell cultures by induction of differentiation. The results of this study showed that neural progenitors obtained from fetal rat CNS generated hair cell immunophenotypes with expression of both epitopes of hair cell marker proteins Brn-3c and myosin VIIa in vitro. These findings indicate that immature neural progenitors possess the potential to differentiate into hair cell phenotypes. Immature neural progenitors may be useful as materials for cell transplantation therapy for replacement of damaged inner ear hair cells.