Damaged lungs may still be viable for transplant

There is still quite a bit of research to be done. Researchers must determine the long-term potential of the repair to the lungs--or whether it's just a quick-fix--and how well the lungs will actually function within a human body. So far, they have tested well inside a see-through life-support dome in the laboratory.

If this proves to be a successful option, the benefits to the medical world are obvious.

"This approach has the potential to change the way we do things," said Dr. Michael Bousamra, who is the lung transplant chief at Jewish Hospital in Lousvilly, Ky.

Currently, only about 15 percent of the lungs now donated from otherwise good organ donors are able to be used for transplant.

In many cases, the lungs are healthy, but the airways were damaged in efforts to keep the donor alive, or brain death caused inflammation that caused damage.

Of course, complications do not end once the transplant surgery is complete. Lungs that are transplanted are very vulnerable to inflammation in the first three days after surgery.

Because of these possible complications, the five-year survival of lung transplant recipients is barely 50 percent.

With the ability to repair lungs that are classified "unusable," the percentage of lungs that could be transplanted could increase significantly, making organs available for many more people.

Researchers' first goal is to save donated lungs that would not normally be used. After that, they hope to also prevent post-surgery inflammation and damage, as well.

The key to repairing damaged transplant lungs is found in a gene that produces a substance called interleukin-10. One of IL-10's functions is stopping inflammation to molecules that are most prone to damage the lungs. The problem in donated lungs is that when they are donated, they are quickly put on ice to prevent deterioration, which prevents IL-10 from working.

The fix, devised by Dr. Shaf Keshavjee, University Health Network's lung transplant chief, is two parts.

First, a body-temperature chamber was created to keep the lungs alive outside the body. Within the dome, a solution of oxygen and nutrients is pumped into them, mimicking the body.

Second, the damage needed to be repaired. Keshavjee's team used an adenovirus, from the family of cold viruses, and inserted the IL-10 gene into it. The virus was then put into the lungs inside the chamber.

After a handful of trials using the lungs of pigs, the team used 10 donor lungs that had been classified as unusable for transplant. The lungs that received the gene therapy showed significant improvement in the ability to take in fresh oxygen, as well as get rid of carbon dioxide.

The human lungs were not transplanted into patients. However, lungs were transplanted into pigs, and after four hours, the repaired lungs were functioning significantly better than lungs that did not receive gene therapy.

Quite a bit of work remains, but if research continues on this path, it could mean a new world for lung transplantation.

Written by Nicole Palmby