Electricity burned through Mr P's body. A metallic odor filled the operating room with layers of fat unraveling. Within a few minutes, a vein split open and filled the field with blood.
It's Zap! The juice turned into a dark mass.
Dr Brandon Guenthart is a cardiothoraic surgeon at the school. The patient was put to sleep after the team confirmed the heart looked good. The surgeons operate before the donor heart arrives. They don't start cutting the patient's heart out until the donor heart is in the air.
If the plane crashes. Guenthart said to knock on wood. The operating room lacks wood.
I was at the hospital to watch the transplant because of my interest in David Bennett, a 57-year-old man who had died earlier this year. Bennett received a heart transplant from a genetically modified pig at the University of Maryland Medical Center.
Over 100,000 Americans are still waiting for a transplant, despite a record number of human-to-human organ transplants performed in 2011. 17 people die every day because there aren't enough organs.
Transferring cells, tissues and organs between species promises to solve the shortage and change how we think about human lifespan.
The significance of the human- animal divide is lost. People walking around with pig organs melded into their bodies can seem like a bad idea. With the zoonotic sars-coV-2 virus having killed more than 6 million people, violating the interface between humans and animals may be a recipe for disaster.
The torturous relationship is nothing new, but it is often hidden from view. The most complex question is what does it mean to be human.
A uman is an animal. Humans and animals are not the same thing. Our history is filled with cultural imaginations of hybridity. The ancient Egyptian god of the sky was depicted with a falcon head and a lioness. The Hindu god was beheaded and then resurrected with an elephant head. The myth of the bull-headed Minotaur was one of the many myths of ancient Greece.
The Lamassu is an Assyrian deity with the body of a bull, the wings of a bird, and the head of a man.
The field of senotransplantation began with cells and tissues. In the 17th century, blood was transfused from animals to humans to cure a lot of diseases. One recipient wrote in a letter to the Royal Society that sheep's blood has a symbolic relationship with Jesus' blood. At least two others died soon after these "xenotransfusions" after one patient's violent fever was supposedly cured.
The first xenotransplants would include the bone, cornea, and skin. Serge Voronoff, a French surgeon, made a name for himself by implanting slices of primate and ape testicles into men and women to improve their health. Thousands of these operations were performed around the world, but any reported benefit, such as reduced fatigue or increased sex drive, was likely only a placebo effect.
Whole organ transplants were more difficult to perform than cell and tissue transplants. It is difficult to sew all the vessels together. You have to tie the two floppy tubes together so that the patient doesn't bleed out and that the patient doesn't have major bleeding either.
This was a prize-level problem that the French surgeon was able to solve with a small needle and thread. He is known as the father of transplants.
The world's first cardiac transplant took place in 1964, when the University of Mississippi surgeon tried to transplant Bino the Chimp's heart into the chest of a patient who was rapidly dying. Rush did not survive for long, with the chimp heart giving insufficient support and rejection shutting down his body.
The stakes for xenotransplantation were set by baby fae. Hypoplastic left heart syndrome is a congenital abnormality where the left side of the heart is a small part. There was a death sentence attached to it.
In 1984 surgeons at a California university performed a transplant on a baby. The conditions were pretty good. The heart was large, the immune system was immature, and the drug cyclosporine was able to suppress attacks on the baboon heart.
The baby appeared to be doing well after the surgery. The hospital spokeswoman said that she was crying and gulping down her formula while resting in her crib. The photos of Baby Fae talking with her mom were released by the hospital.
Her immune system wouldn't accept the baby-baboon hybrid and she died 21 days later. There was outrage from physicians and the public, with animal-rights activists protesting and bioethicists publishing articles.
Baby Fae was the only one who died of phe transplantation.
Guenthart said that during surgery it is not a person. That is a task.
A heart transplant is not difficult. To cut out the failing heart and put in a new one, you only have to make five cuts. The superior vena cava is the most accessible part of the body and is cut out first.
The inferior vena cava is difficult to get to and brings blood from down south. You cut off part of the heart's right chamber.
The aorta and pulmonary arteries are relatively easy to open. The pulmonary veins are not easy to connect. Lift the heart up and cut out the left heart tissue from under it. Guenthart said that you create a swimming pool. He stopped. I just gave a description. It isn't actually called a swimming pool.
The steps are the same regardless of whether you transplant a human or pig heart.
Guenthart said that doctors wouldn't be able to tell you if they were looking at a human or pig chest.
Conventional wisdom says that p igs are filthy. Pork is not allowed in Judaism or Islam. Cops are pigs, that's what the insult means. In the Odyssey, the sorceress turned Odysseus's men into pigs.
The pigs are capable of showing emotion. The benefit to allyship with humans may have been the reason why wild pigs have domesticated themselves. According to their IQ tests, they can outsmart dogs and Chimpanzees.
Pig became the new model for research after the Baby Fae experiment.
If you want to know why pigs are better than baboons, you can ask the experts, who will give you a long list of reasons.
According to Dr Brad Bolman, historian of science at the University of Chicago, sheep, goats, and other animals could have been used instead. It wasn't obvious that pigs were the right replacement for non-human primate The scientific ideals were built retroactively to make pigs seem like the clear choice.
According to Bolman, pigs were chosen because they were convenient. The piglets reach human size in six months. 700 million of them are available worldwide and they aren't covered by the animal welfare act.
"We treat pigs in ways that we wouldn't treat people, but we also recognize they're so similar to us that they're our models." It doesn't make sense, so you can't make sense of it. It's one big problem. Pigs are close enough to give their lives for us, but not close enough to give them pause.
Perhaps it should. It feels exploitative to genetically modify a pig and kill it for its heart if you subscribe to the ethics of the Kantian church. According to People for the Ethical Treatment of Animals, pig-to-human transplants are unethical, dangerous, and a huge waste of resources. A senior vice-president at Peta declared that pigs are people.
These ethical concerns have been around for a long time. The Halloween Parade in New York City was protested in 1999 by members of the Campaign for Responsible Transplantation. As millions of Americans watched the parade on tv, these snout-wearing attendants hoisted a 13ft- tall mad scientist puppet, sporting a dollar sign tie and clenching a pig-human hybrid.
The structural fact of the global pork industry was cited by the experts as the reason for their dismissal of ethical concerns. The thought is that if pigs are going to be eaten, they should be used for science.
Bolman said that eating is about consumption and making animals destroyable. The edibility of pigs justify their use for research and transplants.
Bolman said that science consumes animals even if they aren't actually eaten. Science is still avaiable.
Guenthart was zigging and Zagging a fine thread across the arcs of two vessels to cinch them together after Mr P's new heart arrived in the operating room a half hour ago.
Guenthart ran around counterclockwise after stitching together one of the arteries. He threw a right-handed knot after the two sutures had met. Guenthart was dancing with the fine thread as he threw the last one into a square knot.
The operating room was so quiet that you could hear the music that had been playing. With the donor heart dying, Guenthart was sewing as quickly as possible to restore blood flow to the heart. It was every second that mattered.
Guenthart said, 'Clamp off'. Blood flowed into the coronary arteries from savesay savesay savesay savesay savesay released the pressure off the aorta
Guenhart joked that "xenotransplant is the promise that's 10 years out - and always will be" after graduating from medical school. Bennett's 60-day survival is an amazing milestone and is the most promising solution for the organ shortage.
The new heart of Mr P started beating on its own after 30 seconds. Guenthart didn't have anything to his brain. The circusmaster of its own show is the heart.
X enotransplantation involves humanizing a pig. If you transplant a pig heart into a human, it won't work. According to Dr Richard Pierson, director of the Center for Transplantation Sciences at Massachusetts general hospital, it will turn an ugly black. As he was speeding to the hospital for a human-to-human lung transplant, I talked to him.
The Virginia-based company Revivicor used the Crispr technology to create a special line of pigs with 10 modifications. Six genes are added in.
The recipe for making a pig heart is not known.
1. Knock out three sugar genes that are only found in pigs. “Most of us think if you have a pig with those three genes knocked out, that’s probably better than just one. We don’t know that for sure,” Pierson said.
2. Knock out a growth hormone gene to prevent the pig heart from overgrowing its new home. Pierson said, “Is growth at the graft going to be a problem? We don’t know.”
3. Add two complement inhibitor genes that prevent antibodies from destroying the pig heart and two anti-clotting genes that stop the patient’s blood from curdling inside the foreign organ.
4. Add two anti-inflammatory genes to prevent the pig heart from swelling up. One of these genes signals to the immune system that the pig heart is a friend (self), not food (nonself). “That may or may not be necessary,” said Pierson. “It probably is helpful, but we haven’t proven that.”
The next challenge is to keep the pig free of diseases. You don't want a pig heart to be used to transplant a human heart.
These pigs are raised in a safe environment. There are no doors. They stay inside. Dr Buhler is a professor of surgery at the University of Fribourg.
The surrogate sows have to have a Caesarian section after the genetically engineered embryos are implanted. The piglets are immediately taken to isolation boxes and allowed to suckle their mother only for two hours a day.
The sows are removed from the facility and the piglets are fed a formula and a motherless rearing system. Personal protective equipment must be used when interacting with humans.
You should get a line of pigs that have never been in contact with the outside world and whose Viruses have all been wiped out. The pig hearts are safe to implant into people.
It's not quite right. Bennett had his heart tested for pig retroviruses, which can jump into human cells in a petri dish. It is an example of zoonosis that could lead to a disaster.
Pierson doesn't think that the viruses will be a big barrier to xenotransplantation. eGenesis has made a pig that is PERV-free, and HIV drugs seem to be effective against them.
What do you think is the greatest concern about xenotransplantation?
He called it the unknown unknown. You might only find what you are looking for if you run a lot of tests. Any infections that cross the pig-human barrier could wreak havoc with our immune system.
This all feels a bit premature. I want to know what you think.
There is no reason to worry. You need to be careful. You try to find a way to solve the problem. You don't just return to your house.
The details of Bennett's transplant were revealed in the New England Journal of Medicine in June. Bennett was found to be carrying a pig virus. The paper is neutral on Bennett's cause of death, but the cardiothoracic surgeon and study first-author is slightly betting that Bennett died of a pig virus.
He is referring to a pig virus that is not a PERV.
Mononucleosis, the kissing disease, is caused by the human form of pCMV. Don't allow that to fool you. Inflammation and damage to the organ are caused by cytomegalo virus. A large amount of damage.
The pCMV is one of the viruses that Revivicor said they had eliminated from pigs.
"When it first showed up, we thought maybe it was an error or something, but we had a blood draw on the 20th day after surgery and it came back a tiny blip."
The possibility of a pCMV infection was so unthinkable to the team that they didn't even look for it. We went to the company and asked how we could possibly be seeing this.
A xenotransplantation expert who wishes to remain anonymous thinks that Revivicor may have gotten a bit slack about their protocol. He says the evidence shows that pigs don't get pCMV when they're early on in their lives.
That’s how you make progress. You admit where you made errors, and you try to limit them. But you move on.
Revivicor tested the donor pig several times, and got negative results all the time. Buhler wrote to me that he thought it was not enough to exclude silent pCMV. Revivicor made an honest mistake by not using a more specific test, according to him. Revivicor did not reply to many questions from the Guardian.
The results of the autopsy were gruesome. The virus seemed to have killed the heart after hitchhiking into Bennett.
Even if he isn't entirely sure why Bennett died, Griffith is hoping to do another xenotransplant in the near future. He believes that it can be overcome. Is it a pCMV infections? Don't include it. It's too much immunosuppression. Don't increase it. Bennett was given anti-pig antibodies. Don't do that again
It is how you make progress. You try to limit the amount of mistakes you make. But you don't stop.
What does it mean for there to be a human- animal divide in a world where we are humanizing pigs with Crispr and piggifying humans with transplants?
The worddivide is problematic in some respects. Humans and other animals are not separated by a bright red line. 98% of genes are shared by pigs and humans. It's 2%.
The idea of a human- animal divide is an artificial construct according to the Harvard bioethicist. She said that the research community has been trying to improve the perception of the divide.
Over the course of thousands of years, the separation between animals and humans has been restored. The impossibly low sticker prices of a pack of bacon hides environmental externalities and inhumane conditions. It is easier to not think too much about it.
We have to think about it. We will have to create a new economy of factory farming where pigs will be manufactured and slaughtered to give us life if the promise is to be fulfilled.
1.5 billion pigs are slaughtered every year. If the people you loved most had heart failure, lungs slowly drown in fluid, their dilated heart twisting, you would probably take the pig heart. I would definitely do that. The need to tread carefully here shouldn't be washed away by that.
The OneHealth framework suggests that human, animal and environmental health are all connected.
The NIPah virus is an example. In Malaysia, Singapore, Bangladesh and India, there have been deaths from a disease called NIPah. For a long time, epidemiologists couldn't understand how fruit bats and humans were able to transmit a disease. It took a broadened perspective to solve the puzzle of how date palm trees bloom in the winter, how fruit bats bring saliva and urine to the tree, and how humans eat the tree's sap.
It's not easy to say pigs are people. It's too easy to say pigs have an unlimited supply of organs. Seventeen people die every day waiting for a transplant, but it's not just saving their lives that's important.
All of us are part of the ecology. There is a danger that we ignore our interconnectedness.
Guenthart told Mr P that he was going to get a new heart. Mr P began to cry. Three months ago, his heart began to fail without any apparent reason. His doctors don't know why.
Guenthart said it was difficult to not start crying.
For the patient, a heart transplant is a chance to live. David Bennett was given two more months of life after he had his pig heart transplant. The Rams won the Superbowl. He was singing with his therapist. Every day he begged his surgeons to let him return to his dog Lucky.
Guenthart was talking to Mr P's mom after the transplant.
The surgery was a success. The new heart is doing great. We are sending him to sleep in the intensive care unit because he is sleeping.
He is going to be above where he was before.
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