Usher Syndrome modelling with human induced pluripotent stem cells.
Usher Syndrome is an incurable genetic disorder causing hearing loss and visual impairment responsible for over 50% of deafblind people in the world. There are 3 subtypes of Usher Syndrome which cause different degrees of severity depending on the mutations involved. Severe hearing loss and visual impairment may develop in childhood, early adulthood or even middle age, thoroughly disrupting the lives of those affected. There is no cure for Usher syndrome and currently treatment for Usher Syndrome-related hearing loss is through hearing aids and cochlear implants. However, research suggests new treatment of gene therapy or cell therapies may offer a cure.
We are working with the retinal specialist Professor Fred Chen at Lions Eye Institute to understand how Usher affects eyes and ears, and to try to find common methods to correct the defects. This collaboration provides great economy of effort for our Usher research program and new ideas come from the different perspectives each partner brings. In our current research we are investigating how to make cells of the inner ear from Usher patient stem cells. If the stem cells can be turned into the hearing cells that are missing in Usher patients, we may be able to correct the mutation and put the corrected cells back into the patient’s cochlea to restore hearing. In other words, by changing stem cells so they become the cell type in the ear that detects sounds and then implanting these cells into the inner ear, we hope to restore hearing in Usher syndrome patients. Using this same process Prof Chen will put cells back into the retina and restore sight. This approach is reliant on the ability to model the correct cell type and this represents a major effort for inner ear cell biology in our lab. A robust cell model will allow us to explore many aspects of inner ear cell biology and cell/tissue engineering in the search for a cure for Usher Syndrome.
The genetic makeup of patients is also being investigated so that we can develop induced pluripotent stem cell based models from the various mutations that occur in these Usher patients.
Following the development of these key stem cells, we will explore a number of therapies with the aim to replicate the cells of the inner ear.