Grow-your-own organs could be available for desperately ill patients within five years, after scientists successfully transplanted bioengineered lungs into pigs for the first time.

The team at the University of Texas Medical Branch (UTMB) showed that lab-grown organs were quickly accepted by the animals, and within just two weeks had developed a network of blood vessels.

Previous attempts have failed with several hours of transplantation because the organs did not establish the complicated web of vessels needed for proper oxygen and blood flow.

But the new experiments showed the lungs were still functioning two months after they were implanted and the animals had 100 per cent oxygen saturation, meaning all their red blood cells were carrying oxygen through the body.

Surgical team at UTMB during pig lung transplant credit: UTMB

The method could help solve Britain’s organ donation crisis. There are around 7,000 people on the donor waiting list of which 350 need a lung transplant for conditions like cystic fibrosis and emphysema, but one quarter will die before a suitable organ is found.

“Our ultimate goal is to eventually provide new options for the many people awaiting a transplant,” said Joan Nichols, Professor of Internal Medicine at UTMB.

“Somewhere down the line we may be able to take stem cells from a person and produce and organ that is their organ, tissue matched to them, with no immune suppression needed that would function the way their own lung originally did.”

Joaquin Cortiella, Director of Lab of Tissue Engineering and Organ Regeneration Director, Lab of Tissue Engineering and Organ Regeneration at UTMB added: “I would say in five to 10 years you will get someone with a bioengineered lung.”

Dr Joan Nichols and Dr Joaquin Cortiella in their lab credit: UTMB

To grow the organs in the lab, scientists took the lung of a separate pig and stripped it of its blood and cells using a special mix of sugar and detergent, so that only the ‘skeleton’ remained.

They then created a cocktail of nutrients and lung cells from the pig which was to receive the transplant, and placed it in a tank with the organ skeleton.

The lungs were grown for 30 days and implanted into four pigs who were kept alive for 10 hours, two weeks, one month and two months to see how blood vessels were developing.

All of the pigs that received a bioengineered lung stayed healthy.

As early as two weeks post-transplant, the bioengineered lung had established the network of blood vessels needed for the lung to survive. And there was no sign of too much fluid in the lungs, known as pulmonary edema, which can cause respiratory failure.

The bioengineered lung being prepared

Currently, donated lungs need to be adjusted to fit the size of the patient, and the recipient must take immunosuppressive drugs to decrease the risk of organ rejection. But if seeded with their own cells, the organ would not be rejected.

Although in the short term a human donor lung would be need to create a scaffold, it is likely that in the future, organ 'skeletons' would be 3D printed.

“We were able to make much better vasculature in the lungs which hasn’t been done before,” added Dr Cortiella.

“We were also able to improve from small animal studies to then transplanting them into a larger animal with a larger lung.

“Bioengineered lungs can be made at any time so an individual does not have to wait until an organ is available for them. You can make it for a paediatric patient as well as an adult patient.”

The next steps will to keep the animals alive for longer to allow the bioengineered lungs to fully mature but the researchers say that they should be able to start trials in terminally ill patients within the next five to 10 years.

"It has taken a lot of heart and 15 years of research to get us this far, our team has done something incredible with a ridiculously small budget and an amazingly dedicated group of people," added Prof Nichols.

The research was published in the journal Science Translational Medicine.