A ‘Reversible’ Form of Death? Scientists Revive Cells in Dead Pigs’ Organs.

The pig lay dead in the lab for an hour — no blood was circulating in its body, its heart was still, and its brain waves were flat. A group of Yale University scientists then used a device similar to a heart-lung machine to pump a custom solution into the bodies of dead pigs.

What happened next calls into question what science sees as the wall between life and death. I never thought the pigs were conscious, but the cells that seemed dead were revived. Their hearts began to beat as a solution the scientist called his OrganEx circulated through the veins and arteries. The cells in organs such as the heart, liver, kidneys, and brain were working again, and the animals weren’t stiff like a typical dead pig.

Other pigs that died an hour were treated with ECMO, a machine that pumps blood through their bodies. I made it.

group reported the results Wednesday in nature.

Researchers say their goal is to one day increase the supply of human organs for transplantation by making viable organs available to doctors long after death. They also hope their technology can be used to prevent serious damage to the heart after a fatal heart attack and the brain after a major stroke.

But the discovery is just the first step, said Steven Latham, a bioethicist at Yale University who worked closely with the group. He emphasized that the technology is “far from human use.”

Led by Dr. Nenad Sestan, professor of neuroscience, comparative medicine, genetics, and psychiatry at Yale Medical School, the group was struck by its ability to revive cells.

“We didn’t know what to expect. Everything we restored was incredible for us.”

Others unrelated to the work were equally astonished.

Nita Farahani, a law professor at Duke University who studies the ethical, legal and social implications of emerging technologies, said:

Faraney added that the study raises questions about the definition of death.

“We speculate that death is a thing and a state of being,” she said. “Is there a form of reversible death? Or not?”

This work began several years ago when the group did. Similar experiment In the brains of pigs that died in the slaughterhouse. Four hours after the pig died, the group injected him with a solution called BrainEx, similar to his OrganEx, and confirmed that brain cells that should have died revived.

Dr. Zvonimir Vrsella, another member of the Yale team, said it got them asking if they could revive the whole body.

The OrganEx solution contains nutrients, anti-inflammatory drugs, drugs that prevent cell death, neuroleptic drugs (substances that suppress neuronal activity and prevent the pig from regaining consciousness), and artificial blood mixed with each animal’s own blood. contained hemoglobin.

When they treated pigs that died, investigators took precautions to ensure that the animals were not suffering. continued throughout the experiment. Additionally, the nerve blockers in OrganEx solutions prevent nerve firing to ensure the brain is inactive. The researchers also chilled the animals to slow chemical reactions. Individual brain cells were alive, but there was no sign of organized global neural activity within the brain.

I made one surprising discovery. The OrganEx-treated pigs jerked their heads when researchers injected an iodine contrast agent solution for imaging. Dr. Latham stressed that the reason for this movement is unclear, but there is no indication that the brain is involved.

Yale University has applied for a patent on this technology. According to Dr. Sestan, the next step is to see if the organ is functioning properly and can be successfully transplanted. Some time later, researchers hope to test whether the method can repair damaged hearts and brains.

The journal Nature invited two independent experts to comment on the study. in oneDr. Robert Porte, a transplant surgeon at the University of Groningen in the Netherlands, discussed the potential use of the system to expand the pool of organs available for transplantation.

In a telephone interview, he explained that OrganEx could be used in the future in situations where patients are not brain dead, but have sustained brain damage to the extent that life support is ineffective.

Most countries have a five-minute “no-contact” policy after the ventilator is turned off and before the organ is removed by a transplant surgeon, Dr. Porte said. However, “a few more minutes pass before we rush to the operating room, by which time the organ may be damaged and rendered unusable.

Also, some patients do not die immediately when life support stops, but their hearts beat too weakly to keep their organs healthy.

“In most countries, transplant teams wait two hours for a patient to die,” Dr. Porte said. And if the patient isn’t dead yet, he said, they won’t try to take out the organ.

As a result, 50% to 60% of patients who died after life support was turned off and whose family wanted to donate organs were not donors.

If OrganEx can revive these organs, the number of organs available for transplantation will increase significantly, and the impact will be “huge,” Dr. Porte said.

of other comments It was by attorney and ethicist Brendan Parent, director of transplant ethics and policy studies at New York University’s Grossman School of Medicine.

In a phone interview, he spoke about the “tricky questions of life and death” posed by OrganEx.

“By the accepted medical and legal definition of death, these pigs were dead,” Parent said. But he added, “The key question is which features and what features change things.”

If the group didn’t use neuroleptics in the solution and the pig brains worked again, would the pigs still be dead? If it regains consciousness, it raises ethical questions.

However, if a patient has had a severe stroke or drowned, restoring brain function may be the goal.

“To make this technology useful for people, we need to see what happens in the brain without neuroleptics,” said Parent.

In his opinion, this method must ultimately be tested on those who might benefit, such as victims of stroke or drowning. It requires a lot of deliberation by scientists.

“How to get there will be the key question,” Parent said. “When does the data we have justify this leap?

Another issue is the impact of OrganEx on the definition of death.

If OrganEx continues to show that the time it takes for cells to fail to recover after blood and oxygen deprivation is much longer than previously thought, there will be a shift in the time people are judged dead. must.

“It’s strange, but it’s no different than what we’ve been through in ventilator development,” Parent said.

“There are many people who would have died at another time,” he said.