“It was either die or do this transplant. I want to live. I know it’s a shot in the dark, but it’s my last choice,” said Bennett.
The heart was provided by Revivicor, a company based in Virginia that has been engineering pig organs for roughly two decades. In several experiments for pig-to-baboon transplants, the organs survived up to nine months, until the animals passed away due to a lung infection unrelated to the transplant.
Overall, the heart had 10 hefty genetic edits. Three of them wiped out sugar molecules on the outside of cells that provoke an immune response. Six bolstered the chance of the human host accepting the heart—amping up an anti-inflammatory response, preventing blood vessel damage, and dampening any antibodies against the organ. Finally, the last edit limited the pig heart’s size. Although it generally matched the size of a human heart, the team wanted to prevent the pig organ from overgrowth inside Bennett’s chest once it was transplanted—something they previously noticed happened in baboons.
