Cell regeneration in human vestibular system paves way for therapy into treating balance disorders.
20 September 2018
Pioneering work by Dr Ruth Taylor and colleagues has found that cells with hair cell like properties can be regenerated in the human vestibular system.
Dizziness and balance disorders are significantly underappreciated and are particularly prevalent in the elderly population representing a significant health care burden. These disorders can arise from, among other things, a loss of hair cells in the vestibular system. Unlike in other parts of the animal kingdom, hair cell regeneration does not occur naturally in humans.
Dr Ruth Taylor and her colleagues found a way of generating cells with hair cell like properties in the human vestibular system, suggesting it to be a potentially feasible therapy for some forms of balance disorders including where there is age related loss of vestibular hair cells.
How they did it
In the vestibular system of mice supporting cells can be induced to convert to hair cells, either using certain biochemicals, or by transferring into them a gene, called Atoh1. During embryonic development this gene switches on in the inner ear the pathway through which a non-specialised precursor cell becomes a hair cell.
They collected and maintained vestibular tissues from patients undergoing specific surgery in which this tissue is normally destroyed. “After we removed all the existing hair cells so that predominantly supporting cells remained, transfer of the ATOH1 gene resulted in generation of significant numbers of cells exhibiting many features characteristic of hair cells” says Dr. Taylor.
“Specific biochemical agents also led to cells with hair cell-like features, but in fewer numbers. Analysis of all the genes switched on after ATOH1 transfer revealed a number of genes known to be markers of hair cells. The results demonstrate that supporting cells in the human vestibular system can be induced to convert towards hair cells”
Several “hair cell” genes were not expressed however, and the cells did not form some key structural features of mature hair cells suggesting additional factors are necessary for generating fully functional hair cells.
The study also provides insights into potential means to regenerate hair cells in the cochlea as a therapy for hearing impairment, which is also increasingly prevalent in the ageing population.