Wednesday, November 19, 2008

Claudia Castillo gets windpipe tailor-made from her own stem cells

A woman has been given a new section of windpipe created from her own stem cells in an operation that could revolutionise surgery.

Claudia Castillo, 30, who lives in Barcelona, has become the first person to be given a whole organ tailor-made for her in laboratories across Europe.

A graft from a donor was used, but because it has been imbued with Ms Castillo’s own cells, there is no sign that her body will reject the organ. Researchers and surgeons from Britain, Italy and Spain collaborated to grow tissue from Ms Castillo’s own bone marrow stem cells, using them to fashion the new bronchus – a branch of the windpipe. They believe that one day the approach will be used to create engineered replacements for other damaged organs, such as the bowel or bladder. In five years they hope to begin clinical trials in which laboratory-made voice boxes are implanted into patients with cancer of the larynx.

Martin Birchall, of the University of Bristol, a British member of the team, said: “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 – it will transform the way we think about surgery.”

Ms Castillo, who was born in Colombia, had suffered a tuberculosis infection that ravaged her airways, leaving her unable to do simple domestic tasks. Disease had caused her windpipe, or trachea, to collapse just at the point where it entered her lung. Without the pioneering operation in June, the lung would have been removed. Today she again has a normal life and is able to look after her two children. She can walk up stairs without getting breathless and has even been dancing.

The prospect of the patient needing powerful drugs to avoid rejection had been thought to outweigh any potential benefits of trachea transplants. Four months on, Ms Castillo’s doctors have seen no sign of her immune system rejecting the transplant, even though she has had no immunosuppres-sive drugs.

Details of the transplant, performed by Paolo Macchiarini, at the Hospital Clinic of Barcelona, are published online today by The Lancet.

First a section of trachea was taken from a donor and stripped of cells that could cause an immune reaction, leaving a grey trunk of connective tissue. Stem cells were then taken from Ms Castillo’s bone marrow and grown in Professor Birchall’s laboratory. Stem cells can develop into different kinds of tissue, given the right chemical instructions, enabling researchers to cultivate cartilage and epithelial cells to cover the 7cm graft. It was then “seeded” with the new cells using a process developed in Milan. Finally the trachea, covered in cartilage and lined with epithelial cells, was cut to shape and fitted.

Professor Macchiarini said: “The probability that this lady will have rejection is almost zero. She is enjoying a normal life, which for us clinicians is the most beautiful gift.”

The researchers said that the surgery could help some patients in Britain but admitted that the procedure was too expensive to be widely available. They are seeking EU funding and commercial sponsors for trials to create and transplant a larynx, an operation that could be more cost-effective.

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

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