Up-regulation of stromal cell-derived factor-1 enhances migration of transplanted neural stem cells to injury region following degeneration of spiral ganglion neurons in the adult rat inner ear

► SGN-degenerated cochlear microenvironment plays a beneficial role for NSC migration. ► The role is mediated by the SDF-1. ► The increased SDF-1 protein was derived from the satellite Schwann cells of the spiral ganglion. ► Optimizing SDF-1 expression may improve the migration of stem cells in the cochlea.