An artificial airway created from stem cells has been used to save a woman's left lung in a landmark operation that could revolutionise transplant surgery.

Mother-of-two Claudia Castillo, 30, is the first person in the world to be given a whole laboratory-engineered airway.

She is also believed to be the first transplant patient not to need powerful drugs to subdue the immune system.

Researchers from the UK, Italy and Spain worked together to grow tissue from Ms Castillo's own bone marrow stem cells, use them to fashion a new bronchus - a branch of the windpipe - and carry out the transplant.

The scientists believe in years to come the same approach will be used to create engineered replacements for other damaged organs, such as the bowel, bladder or reproductive tract.

In five years' time they hope to begin clinical trials in which laboratory-made voice boxes are implanted into patients with cancer of the larynx.

Professor Martin Birchall, a British member of the team from the University of Bristol, said: "What we're seeing today is just the beginning. This is the first time a tissue- engineered whole organ has been transplanted into a patient.

"I reckon in 20 years' time it will be the commonest operation surgeons will be doing. I think it will completely transform the way we think about surgery, health and disease."

Colombian-born Ms Castillo, from Barcelona, Spain, had suffered a serious tuberculosis infection that ravaged her airways, leaving her short of breath and unable to carry out the simplest domestic tasks.

Disease had caused her windpipe, or trachea, to collapse just at the point where it entered her left lung. Without the pioneering operation in June, the lung would have been removed by surgeons.

Today Ms Castillo is living an active, normal life, and is once again able to look after her children Johan, 15, and Isabella, four. She can walk up two flights of stairs without getting breathless and has even been dancing in nightclubs.

So far, doctors have seen no hint of her immune system rejecting the transplant, even though she received no immunosuppressive drugs.

Prof Birchall admitted that the decision to turn to tissue engineering to help Ms Castillo was a "leap of faith".

The same procedure had only been attempted on pigs before, but had looked highly promising.

A series of complex steps pushing the boundaries of medical science led up to the transplant operation, performed on June 12 by Professor Paolo Macchiarini at the Hospital Clinic of Barcelona.

Details of the transplant were described today in an early online edition of The Lancet medical journal.

Prof Macchiarini said: "We are terribly excited by these results. Just four days after transplantation, the graft was almost indistinguishable from adjacent normal bronchi.

Professor Anthony Hollander, another member of the Bristol stem cell team, said: "This is an example of stem cell science becoming stem cell medicine."

The scientists are already looking to the future and seeking European Union funding and commercial sponsors for the more ambitious larynx trials.

Ms Castillo said: "I was scared at the beginning because I was the first patient, but had confidence and trusted the doctors. I am now enjoying life and am very happy that my illness has been cured."