The journal, Nature, reports that researchers in the United Kingdom have taken a huge step forward in treating deafness, after stem cells were used to restore hearing in animals for the first time in medical history. Hearing partially improved when nerves in the ear, which pass sounds into the brain, were rebuilt in gerbils using stem cells. The same improvement in people would equivalate to going from being unable to hear heavy traffic, to hearing a conversation.
The aim of researchers at the University of Sheffield was to replace spiral ganglion neurons, with new ones, so they used stem cells from a human embryo, and over 10 weeks, the gerbils’ hearing improved. To put into scale, Dr Marcelo Rivolta said, “It would mean going from being so deaf that you wouldn’t be able to hear a lorry or truck in the street, to the point where you would be able to hear a conversation. It is not a complete cure, they will not be able to hear a whisper, but they would certainly be able to maintain a conversation in a room.”
About a third of the gerbils responded really well to treatment, with some regaining up to 90% of their hearing, while the average improvement was 45%, with just under a third having a minimal response. Gerbils were used for the study, as they hear a similar range of sounds that humans do, unlike mice which hear higher-pitched sounds.
Dr Ralph Holme, head of biomedical research for the charity Action on Hearing Loss, said, “The research is tremendously encouraging and gives us real hope that it will be possible to fix the actual cause of some types of hearing loss in the future. For the millions of people for whom hearing loss is eroding their quality of life, this can’t come soon enough.”