Scientists repair damaged lungs for transplantation

The new study has raised hopes among lung specialists who believe that this will significantly help people who need lung transplantation.

Dr. Michael Bousamra of the University of Louisville, said, “We’ve been banging our heads against the wall with respect to lung transplant survival for quite some time.”

However, further research studies need to be conducted in order to determine how long the repaired lungs can work.

Also, it needs to be seen if the lungs function as efficiently back inside a body as they do inside a see-through life-support dome in the laboratory.

Dr. Bousamra added that it will still take a long time before the new study results start being utilised on a large scale. But, he said, “This approach has the potential to change the way we do things.”

Transplantation rate for donated lungs very low
At present, only 15 percent of the lungs donated by good organ donors are utilised for transplant, which is very low.

The main difficulty doctors face is not that the lungs are diseased. Rather, it is the delicate airways that get damaged as doctors make an effort to keep the donor lung alive. Further, brain death can lead to immense inflammation that causes additional damage.

Also, transplanted lungs are very susceptible to inflammation in the first three days post-surgery.

Statistics reveal that the five-year survival rate of lung transplant recipients is hardly 50 percent. This is very low as compared to heart, liver or kidney recipients.

Therefore, the researchers from Toronto’s University Health Network will focus on how to save the donated lungs. If they succeed in this, they might be able to find a permanent solution to post-transplant damage too.

Two-part fix for lungs devised by Keshavjee
The key to saving the donated lungs lies in a gene that produces a substance called interleukin-10 (IL-10). IL-10 is responsible for compressing inflammation in the molecules that are most likely to damage lungs.

But as soon as the lungs are donated, they are put on ice to prevent further declining of the tissues. This halts the working of IL-10.

So, Dr. Shaf Keshavjee, lung transplant chief from the University Health Network, came up with a two-part fix.

The first step was to generate a body-temperature chamber that would aid in keeping the lungs alive outside the body. They first utilised lungs from a few pigs and then from humans.

His research team created a protective dome in which the lungs were placed. A solution of oxygen and nutrients was then pumped into them. This arrangement resembled that of the human body but minus the blood.

The second step was to insert a gene into those lungs that would immediately lead to the production of huge levels of IL-10 and ultimately reverse the inflammation.

The research team has reported that this two-step fix works well. They also discovered that lungs treated with the gene therapy had an increased capacity to take in fresh oxygen and get rid of carbon dioxide.

Keshavjee was quoted as saying, “The beauty of what we’re doing here is, we’re transducing the cells in the lung to become little IL-10 factories.” However, these repaired human lungs were not transplanted into sick patients. Rather, they were transplanted into pigs.

It was found that they performed their function much better four hours after transplant as compared to lungs that did not get gene therapy.

But Keshavjee is optimistic and hopes to perform an experiment next year where he will transplant the repaired lungs into humans.

The new study findings have been published in the journal Science Translational Medicine.