Hair cell regeneration

Abstract

In 1988, two landmark papers definitively showed that hair cells in the mature avian inner ear can regenerate after otologic insults have destroyed the existing receptors. This discovery, not new to the vertebrate phylum but new for terrestrial vertebrates, has led to a rethinking of the assumption that hair cell loss in mammals, including humans, must necessarily be permanent. In this article, we present a brief progress report on the status of research on hair cell regeneration in birds and mammals. In the brief period since these initial publications, a great deal has been accomplished; we now know much about the process of hair regeneration in birds. We know that it does lead to a recovery of function(s), and we are beginning to get clues about the cellular and molecular events that trigger hair cell regeneration in birds. In mammals, intriguing data are emerging that suggest induction of early stages of the regeneration process, as well as the possibility that more than one cellular route for hair cell replacement may exist. These data do not provide a cure for hearing loss or dizziness, but they do provide a new beacon shining light down a long tunnel, the entrance to which has only recently been opened.