Experimental study on embryonic neural stem cells transplantation into natural rat cochlea via round window / 中华耳鼻咽喉头颈外科杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the survival of neural stem cell (NSC) infected by recombinant adenovirus with GFP (Ad-GFP) and the expression of GFP in normal rat cochlea and their potential effect on auditory function and cochlea structures via round window transplantation.</p><p><b>METHODS</b>In comparison with the normal rats without any transplantation (Group III), normal rat cochleae were transplanted with NSC infected with Ad-GFP (Group I) or the artificial perilymph (Group II) via round windows. Auditory functions were monitored by thresholds of auditory brain stem responses (ABR); the cochlea structures were examined by HE staining; survivals of implanted NSC were determined by the expression of GFP; survivals of hair cells were accessed by whole mount preparation.</p><p><b>RESULTS</b>Neither at pre-transplantation nor at post-transplantation, there were significant differences in the click-ABR thresholds in rats between Group I and Group II (P > 0.05). There were no significant differences in these values before and after transplantation in the same rats from each group. After transplantation, the cochlea structures were normal in both Group I & Group II. Grafted NSC was visualized by the GFP expression in every turn of the cochlea in all animals of Group I. There were no significant differences in the loss of outer hair cell (OHC) among three groups. The inner hair cell (IHC) and most OHC were normal in every turns of cochleae of all groups.</p><p><b>CONCLUSIONS</b>The embryonic NSC infected with Ad-GFP could survive and express the GFP gene in normal rat cochlea after transplantation via round window, which had not obvious affection to auditory function and inner ear pathology of rat cochlea.</p>