BACKGROUND AND OBJECTIVES A considerable portion of the hair follicle remains attached to plucked hair and can be used for follicle cell culture. In this study we have phenotyped these cells in an attempt to identify the stem cell fraction. Reports in the literature have indicated that this cell population may be positive for cytokeratin (CK) 19. Because stem cells in general need to be protect...

Sensory neural hearing loss and vestibular dysfunction have become the most common forms of sensory defects, affecting millions of people worldwide. Developing effective therapies to restore hearing loss is challenging, owing to the limited regenerative capacity of the inner ear hair cells. With recent advances in understanding the developmental biology of mammalian and non-mammalian hair cells...

In the developing cochlea, sensory hair cell differentiation depends on the regulated expression of the bHLH transcription factor Atoh1. In mammals, if hair cells die they do not regenerate, leading to permanent deafness. By contrast, in non-mammalian vertebrates robust regeneration occurs through upregulation of Atoh1 in the surviving supporting cells that surround hair cells, leading to funct...

Sensory hair cells of the inner ear express multiple physiologically defined conductances, including mechanotransduction, Ca(2+), Na(+), and several distinct K(+) conductances, all of which are critical for normal hearing and balance function. Yet, the molecular underpinnings and their specific contributions to sensory signaling in the inner ear remain obscure. We sought to identify hair-cell c...

BACKGROUND At least five bHLH genes regulate cell fate determination and differentiation of sensory neurons, hair cells and supporting cells in the mammalian inner ear. Cross-regulation of Atoh1 and Neurog1 results in hair cell changes in Neurog1 null mice although the nature and mechanism of the cross-regulation has not yet been determined. Neurod1, regulated by both Neurog1 and Atoh1, could b...

Objective; In studies of the sensory epithelium of vestibular organs, regeneration of hair cells was observed. Regeneration capability of hair cells may be considered to suggest the presence of endogenous stem cells that could regenerate damaged hair cells in these organs. Therefore, we tried to show that human vestibular sensory epithelium contains cells that display proliferating characterist...

·--------------------------------------------------------------------------------------------------------············xiv CHAPTER 1: The inner ear and hair cell resonant frequency Introduction: Sensory organs of the inner ear and innervation ..... ------------------------------·--------·1 Hair cell shape and innervation of the cochlea and sacculus ......................... 2 Frequency detection ...

stem cells are the cells having some distinguishing characteristics like longevity, high capacity of self-renewal and differentiation, quiescence and highly error-free proliferation. almost all stem cells have the potential of lineage reprogramming, i.e. inter-conversion of cell lineages. they also have the potential to differentiate into almost all kinds of cells. these cells have been found i...

Inner ear epithelia of mature birds regenerate hair cells after ototoxic or acoustic insult. The lack of markers that selectively label cells in regenerating epithelia and of culture systems composed primarily of progenitor cells has hampered the identification of cellular and molecular interactions that regulate hair cell regeneration. In control basilar papillae, we identified two markers tha...