Hearts taken from genetically-engineered pigs have been successfully transplanted to baboons in trials in Germany.
Four baboons lived in good health for several months after surgery, bringing xenotransplantation (transplanting organs or tissues between members of different species) one step closer to the clinic.
In previous trials, the longest survival has been 57 days.
Bruno Reichart of the University of Munich and colleagues have adopted immunosuppression methods that enable longer survival from the improved transplanting techniques they used.
Pigs are larger than baboons and because they used hearts from young pigs, the hearts grew accordingly. To stop this, the team reduced the baboons’ blood pressure to avoid enlargement and gave the animals a drug to prevent proliferation and growth of cells.
Heart growth may not be an issue for humans because they are a closer size match with pigs.
“I’m not saying that we’re ready to go into the clinic tomorrow,” says Byrne, but “the field can be stuck optimizing for nonhuman primates and get nowhere, when what we really need to do is to begin optimizing in humans.”