One of the world's more active tissue engineering research and development groups works on building replacement tracheas from a scaffold and the patient's own cells. They have carried a number of successful transplants in recent years, and seem on a par with Tengion's work on bladders, or the folk producing heart valves for children in terms of outcomes and technological sophistication.
Here's an update on a transplant carried out late last year:
Surgeons in Sweden have replaced the cancerous windpipe of a Maryland man with one made in a laboratory and seeded with the man's cells.
"What we did is surgically remove his malignant tumor," Dr. Macchiarini said. "Then we replaced the trachea with this tissue-engineered scaffold." The Y-shaped scaffold, fashioned from nano-size fibers of a type of plastic called PET that is commonly used in soda bottles, was seeded with stem cells from Mr. Lyles's bone marrow. It was then placed in a bioreactor - a shoebox-size container holding the stem cells in solution - and rotated like a rotisserie chicken to allow the cells to soak in.
After two of days, it was installed in Mr. Lyles during an elaborate operation in which it was sutured to his throat and lungs. All told, the treatment cost about $450,000, Mr. Lyles said.
Dr. Macchiarini has performed a dozen trachea transplants since 2008, but the first 10 used organs from cadavers in which all the living cells were removed, leaving behind a natural scaffold of cartilage. Donated tracheas are rare, however, and are never a perfect fit. In Mr. Lyle's case, and in the case of an Eritrean man who received a similar transplant last June and is doing well, the synthetic scaffold is made using CT scans of the existing trachea to ensure it matches precisely.
The cost of the first tissue engineered parts will fall dramatically once the procedures become more widespread and the underlying technologies more robust and commoditized. But costs will not fall as far is they would in an actual free market in medicine, and there will be long and unnecessary years of delay - and vast expense for the sponsoring companies - before regulators in wealthy Western countries will approve these new applications of cell science for broad use.