Boy's windpipe replaced in stem cell surgery

The boy, who is convalescing at Great Ormond Street children’s hospital, in London, has not been identified.
He was born with a windpipe that was 1mm across — too narrow for him to be able to breathe unaided.

The boy was given a denuded donated windpipe which was coated just a few hours before the operation with his own stem cells, chemically “programmed” to turn into the appropriate tissues while inside his body.

Professor Martin Birchall, the head of translational regenerative medicine at University College London, said: “It is the first time a child has received stem cell organ treatment, and it’s the longest airway that has ever been replaced.
“We need to conduct more clinical trials to demonstrate that this concept works. We’d like to move to other organs as well, particularly the larynx and oesophagus. We need to think about how to make regenerative medicine a part of healthcare.”
Stem cell pioneer Professor Paolo Macchiarini, of Careggi University hospital, in Florence, who led the Italian, British and Spanish team behind Castillo’s transplant, , tried the new procedure for the first time on a 53-year-old Italian woman last year. She had part of her trachea replaced. The boy’s doctors contacted Macchiarini after they ran out of options. They had tried to patch up his trachea and hold it open with supporting “stents”. But eventually the stents eroded, damaging the aorta, the main artery taking blood out of the heart. A decision was taken to go ahead speedily after the boy’s condition deteriorated last November.

Selecting a donor
In February this year, Prof Macchiarini’s team selected a dead donor from a shortlist of three — a 30-year-old Italian woman. Her trachea was removed, and stripped of its cells using digestive enzymes. All that was left was inert collagen and the “basal membrane” which provided the foundation for cell growth.
Macchiarini joined his British colleagues at Great Ormond Street during the operation, where he took charge of “seeding” the trachea with the stem cells and applying the correct “growth factor” chemicals.Using the new “bionic” technique, the boy’s trachea was ready to be implanted in just four hours.
“The idea is to use the reactions of the body to make the structure living,” said Macchiarini. “We told the cells to differentiate and transform naturally into the layers that make up the airway. This is something that makes tissue regeneration very simple and accessible to everyone.”