Stem cell trachea used to save woman’s lung

AN artificial airway created from stem cells has been used to save a woman’s left lung in a landmark operation that could change the face of transplant surgery.

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

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

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

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 which ravaged her airways, leaving her short of breath and unable to carry out the simplest domestic tasks.

The 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 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.

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.

First a section of windpipe, or trachea, was taken from a 51-year-old woman donor who had died from a cerebral haemorrhage.

This was to provide the scaffold or “matrix” around which the new bronchus would be built.

Using a new technique involving detergent and enzymes, the trachea was stripped of its cells, leaving a grey trunk of connective tissue. The process removed almost all the material that could trigger an adverse immune reaction.

Stem cells from Ms Castillo’s own bone marrow were then grown and multiplied in Prof Birchall’s laboratory, and treated with “growth factor” chemicals to turn them into cartilage cells called chondrocytes.

Next, the 7cm-long trachea had to be “seeded” with two different kinds of cells — the chondrocytes made in Bristol, and specialised epithelial cells derived from tissue taken from Ms Castillo’s nose and healthy airways.

Finally the trachea was cut to shape and slotted into the gap left by the diseased and collapsed bronchus.

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

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.”