Researchers hope the pig-to-primate heart transplant breakthrough will pave the way for the use of animal organs in human transplants. Photo by Africa Studio/Shutterstock

WASHINGTON, April 5 (UPI) -- A team of German and American scientists recently announced an organ transplant breakthrough. The researchers were able to keep a pig heart beating inside a baboon for more than two years.

The body's immune system complicates cross-species organ transplants. Often, the recipient's body rejects the new organ. But scientists used genetic engineering and immunosuppression drugs to keep the baboons from rejecting the pig heart.


Hearts were sourced from a line of pigs genetically engineered to be more compatible with the baboon's immune system. A special regimen of drugs and antibodies ensured the primate's immune system wouldn't overreact.

As part of the experiment, five baboons got five pig hearts. The recipients' hearts weren't replaced. The pig hearts were simply hooked up to the circulatory system, while the baboons' own hearts continues to pump blood.

The pig hearts kept beating for an average of 945 days.

"This milestone shattered previous records of pig-to-primate heart transplant also achieved by this group of researchers over past five years," the National Heart, Lung and Blood Institute announced in a news release.

Pigs are genetically and physiologically similar to humans, making them the logical choice for potential use of animal organs in people. With a growing list of patients awaiting organ donations, scientists have been working on ways to make cross-species organ transplants safer and more effective.

The latest research, published in the journal Nature Communications, offers hope.