Date of Degree


Document Type

Capstone Project

Degree Name





Carol A. Silverman


John Preece

Subject Categories

Speech Pathology and Audiology


Inner ear cell, stem cell, regeneration, avian


Objective: The purpose of this investigation is to review current possible regeneration techniques for damaged hair cells of the inner ear in mammals. The avian has the ability to spontaneously regenerate damaged hair cells, and thus provides an animal model to simulate a similar response in the mammalian inner ear.

Methods: A systematic review of the literature was conducted using a PubMed database search to address the following question What are the current investigations pertaining to regenerating hair cells using stem cell-based research? The articles were analyzed and rated at Level Ia, Ib, IIa, IIb, or III level of evidence. All articles had to be related to the inner ear and stem cell, of English-language and be in peer-reviewed journals from 2005-2010.

Results: Study results indicate that hair cells generated from a stem cell show some morphological and electrophysical similarities to in vivo cells. Nonetheless, generation of hair cells in vivo has still a long way to go before being achieved. Stem cell investigations include not only embryonic stem cells but also adult stem cells from the vestibular system, bone marrow and lateral ventricles. In vivo studies involving transplants of different types of stem cells have been conducted.

Conclusions: Since the finding that avians do spontaneously regenerate damaged hair cells, several researchers have attempted to replicate the factors indicated in the avian regeneration pathways in the human or mammalian model. Although successful replication has remained elusive, such attempts have shed light on the developmental process. The human inner ear is highly organized and extremely sensitive by nature of its function (being able to respond to movement micrometers in length); thus, any intervention -- be it gene therapy based, or stem cell transplantation based -- has proven to be extremely difficult.