Lab-grown pig lungs may signal the future of organ transplants

Researchers at the University of Texas say they have successfully grown pig lungs in the lab — and it may help pave the way for use of lab-grown organs in humans too.

In research published this week in the journal Science Translational Medicine, the U of Texas researchers say they used a lung scaffold — literally the outer casing of lung tissue, called the extracellular matrix — and coated it with a concoction of growth factors and chemicals that stimulate the cells to turn into lung cells.

Previous studies cultured cells for one week and the transplantation ultimately failed. So researchers used a 30-day time frame for this study and were able to develop an immature bioengineered lung, with cells and proper tissue formation.

While our bodies build organs as fetuses, there have been a lot of hurdles to producing lab-grown organs. One of the most significant hurdles has been getting the blood supply to marry up with the organ so that it can survive in the body.

In the U of T research, one pig lung was removed and replaced with the lab-grown lung, and the other natural lung was left.

In this case, the transplanted lungs were integrated into the body and grew normally, the researchers say. Once they connected the lab-grown lung to the blood supply in the host pig's body, blood flowed to the new organ. The blood vessels that carry that blood were mature enough to handle the pressure and the lungs looked almost indistinguishable from a natural lung.

But did the lung work?

While the pigs survived for over a month before being terminated (which the researchers had to do to properly study the lungs) the U of Texas researchers aren't sure if that's due to the new lung functioning.

The pigs were OK living off one lung — their natural lung — and didn't necessarily need to use the lab-grown lung. The lab-grown lung's contribution to the oxygen getting to the body was not measured — so at this point, it's tough to tell whether the lung worked.

The next step of the research is to test whether the newly grown lung works by basically blocking the function of the pig's primary lung and seeing if they can still get oxygen into their blood and to the tissues.

The future of organ transplants

The new findings are good news for anyone on an organ donation list, according to one of the researchers.

"Here's the possibility of us making lungs for people who are waiting on that list and giving them hope," said Dr. Joaquin Cortiella, from the University of Texas medical branch.

The doctors are hoping that within a decade, lab-grown human lungs will be transplanted into patients to save them from chronic lung diseases, cystic fibrosis and anything that threatens life and lungs.