Bringing pigs back to life raises medical hopes

PARIS — Scientists announced on Wednesday that they have restored blood flow and cell function throughout the bodies of pigs that were dead for an hour, in a breakthrough experts say could mean we need to update the definition of death itself.

The discovery raised hopes for a range of future medical uses in humans, the most immediate being that it could help organs last longer, potentially saving the lives of thousands of people worldwide in need of transplants.

However, it could also spur debate about the ethics of such procedures, particularly after some of the ostensibly dead pigs startled the scientists by making sudden head movements during the experiment.

The US-based team stunned the scientific community in 2019 by managing to restore cell function in the brains of pigs hours after they had been decapitated.

For the latest research, published in the journal Nature, the team sought to expand this technique to the entire body.

They induced a heart attack in the anesthetized pigs, which stopped blood flowing through the bodies.

This deprives the body’s cells of oxygen — and without oxygen, cells in mammals die. The pigs then sat dead for an hour.

The scientists then pumped the bodies with a liquid containing the pigs’ own blood, as well as a synthetic form of hemoglobin — the protein that carries oxygen in red blood cells — and drugs that protect cells and prevent blood clots.

Blood started circulating again and many cells began functioning including in vital organs such as the heart, liver and kidney for the next six hours of the experiment.

“These cells were functioning hours after they should not have been — what this tells us is that the demise of cells can be halted,” said Nenad Sestan, the study’s senior author and a researcher at Yale University.

Sam Parnia, associate professor at the NYU Grossman School of Medicine, said it was “a truly remarkable and incredibly significant study”.