Researchers have developed a technique to treat the donor larynx so that the recipient's body accepts it as its own.
Paolo Macchiarini of the Karolinska Institute in Stockholm, Sweden, and colleagues in Italy, who developed the technique, have announced their first successful partial transplant.
AdvertisementTheir technique solved the rejection problem by stripping the donor tissue of cells and DNA before reseeding it with stem cells taken from the recipient's bone marrow.
His team previously pioneered this bioengineering technique for human windpipe transplants.
"But the larynx is more complex than a windpipe," New Scientist quoted Macchiarini as saying.
To find out if the technique could be adapted, his team gained consent to remove the larynxes from five cadavers and treated them with enzymes and detergents to remove donor cells.
Tests showed that just 0.001 per cent of donor DNA remained - quantities small enough to suggest they could be transplanted without rejection.
The larynx contains two types of cartilage - elastic and hyaline - each with distinct properties. The stripped larynxes showed similar mechanical properties to those of a normal larynx, suggesting they could perform with the same degree of versatility after transplant.
Finally, the researchers showed that blood vessels would regrow in the treated larynxes, making it easier for them to integrate with the recipient's body after transplant.
The study is yet to be published in Biomaterials.