A boy who had his defective windpipe replaced with one grown using his own stem cells is growing into a healthy teenager following the world-first operation.
Before Ciaran Finn-Lynch (13) had the operation in London, doctors thought he could die at any moment.
He had been born with a windpipe just one millimetre wide and survived only because of a series of metal devices, called stents, to hold his airway open.
However, these repeatedly burrowed into a major blood vessel causing serious bleeding. One more such bleed and he could have died.
Two years ago, specialists proposed a pioneering technique that involved covering a donor windpipe with Ciaran's stem cells. It was the boy's only option, doctors said.
His family agreed and the operation took place at Great Ormond Street Hospital, London in March 2010.
Ciaran, from Co Down, has since grown almost four-and-a-half inches (11cm) and he has returned to school. He has also developed his musical interest as a drummer. A medical update is published in 'The Lancet' today.
His family has declined to be interviewed, but at the time of the operation his mother Colleen said she and her husband Paul had "got our boy back".
The procedure involved taking a windpipe from a 30-year-old Italian woman who had died and stripping it of living cells down to the inert collagen "scaffold".
Four weeks later, Ciaran's windpipe was removed. Bone marrow from Ciaran was harvested and the stem cells isolated.
The same day, the donor windpipe was inserted into Ciaran's neck and his stem cells sprayed on to it. Tiny sections of lining from his original windpipe were patched on to the replacement. These prompted the stem cells to turn into the right kind of tissue and kickstarted growth of the windpipe lining.
Finally, the graft was injected with proteins called cytokines to stimulate cell growth.
The operation was the first attempt to grow stem cells in place in the body of a child, rather than growing an organ in a laboratory "bioreactor". It came only two years after the first windpipe replacement using stem cells in an adult, although in that case it was carried out in Barcelona and the organ was grown in the laboratory.
Ciaran was fitted with a biodegradeable stent to keep his airway open for the first six months while the windpipe grew into place. After the operation his doctors described it as "a kind of miracle".
Professor Martin Elliott, who led the transplant team at Great Ormond Street Hospital, said yesterday: "The ideal outcomes for tracheal transplants in children are normal airway and lung function, good general growth, a decent quality of life, and no further surgical interventions.
"So far we have achieved this, but we are at the edge of medicine and, similarly to first attempts of organ transplantation in the 1950s, many challenges remain.
"A second child has since undergone a tracheal transplant (at the hospital). Although the graft preparation and the surgery were completed successfully, the child sadly passed away at a later date."
Martin Birchall, professor of laryngology at the University College London Ear Institute, said more research was needed to help convert one-off successes into clinical treatments.
The doctors hope to grow more complex organs such as hearts and intestines but think such "tissue engineering" is still many years away. (© Daily Telegraph, London)