Xenotransplantation of adult human olfactory stem cells into mice with early-onset sensorineural hearing loss

Abstract

The main goals of this thesis are: • To investigate the survival of adult human olfactory stem cells xenotransplanted into a mouse model of early-onset hearing loss (A/J mice). • To evaluate the ability of the stem cells to rescue hearing in early-onset progressive sensorineural hearing loss. The main results of this thesis are: • Xenotransplanted adult human olfactory stem cells survived for 4 weeks after the surgery (end point of the study). • The stem cells were mainly found in perilymphatic compartments of the cochlea (scala vestibuli and scala tympani) while only a few stem cells were present in scala media. • The stem cells did not integrate into cochlear tissues. • Post-surgery hearing threshold levels in stem cell-transplanted mice were found to be significantly lower than threshold levels of sham-injected mice (P < .05) for both click and pure tone stimuli. In addition, the threshold shift (difference between pre and post-surgery hearing thresholds) was significantly less in the stem cell transplanted animals than the sham-injected animals for click stimulus. Overall, adult human olfactory stem cell transplantation can help preserve hearing during early-onset sensorineural hearing loss.This improvement in hearing could be due to paracrine effect of adult human olfactory stem cells.