Researchers in the US have grown functioning vocal cord tissue in a laboratory for the first time.
Scientists based in the University of Wisconsin-Madison in the US developed the tissue using cells from the larynx of a cadaver, as well as tissue from four live patients who had their voice boxes removed.
The cells were grown and put onto a “scaffold” of collagen, a protein found in the make-up of skin, ligaments and tendons.
After about two weeks, the cells formed a tissue, which "felt like vocal-cord tissue," according to lead researcher Dr Nathan Welham.
To test the sound, the newly-built tissue was put in place of one half of the larynx of a dead dog. Then warm, humid air was blown through the structure through a plastic “wind pipe”.
It was found that the new tissue worked in tandem with the real tissue and the sound results were a lot better than Dr Welham and his team predicted.
“We hoped for some decent vibrations, some reasonable voice output,” he said in a video about the development.
“Actually, the function and the vibration of the engineered tissue was exquisite and really pretty much comparable to the normal tissue,” he said.
Building this particular type of tissue isn’t easy, as vocal cords have to be flexible enough to vibrate to produce sound, but also “strong enough to bang together hundreds of times per second”.
“Voice is a pretty amazing thing, yet we don’t give it much thought until something goes wrong,” Dr Welham said.
The team's findings have been published in the journal of Translational Medicine and summarised on the university's website.
