The search to keep organs living outside the body (19459000)
In this week’s article, I discussed a remarkable effort to preserve the organs of deceased donors outside their bodies. The shortage of organ donors is largely due to the fact that they only survive a few hours after being removed from the body.
Organ banks are a dream for doctors. They want to store human organs in a way that they can last days, even weeks or months. This would enable them to test organs and find recipients who are the most compatible.
A team of researchers has managed to preserve the kidneys from pigs, which are similar in size to humans.
They were able to survive being kept at -4 degrees Celsius (25 degrees Fahrenheit) for days and then reimplanted into pigs. This is just one of the many recent developments in an area that has been generating a lot of buzz.
Organs are extremely difficult to freeze. They’re finished once ice has formed. Ice crystals can cause all sorts of damage to organs and make them unusable. Many researchers have tried anyway.
Some have focused on cryopreservation–rapid extreme cooling that essentially leaves cells in a glasslike state. The process has become routine in the storage of eggs, embryos and sperm.
They are all cooled down to -196 degrees Celsius in under two seconds.
Nobody has been able to successfully cryopreserve and defrost human organs in order to transplant them. Many human brains and bodies have been frozen at extremely low temperatures, in hopes that one day they could be brought back to live. You can find out more here about the reasons why people choose cryonics.
I reported in March about Stephen L.
Coles. He was a gerontologist and had chosen to cryopreserve the brain. The scientist’s body was transported to Alcor in Arizona, a facility for cryonics, after he died in 2014.
The team removed Coles’s head and perfused it with cryoprotective chemical (which works like antifreeze). They then removed his brain from the skull and cooled the temperature to -146 degrees Celsius.
Greg Fahy is a cryobiologist who studied Coles’s brain pieces years after the shrinkage.
He found that when they were warmed up again, his friend discovered that these brain cells had “sprung back”. It doesn’t necessarily mean that the cells have life, nor that the brain could be reanimated one day. Matthew Powell Palm, a professor at Texas A&M University told me that there were many possible ways in which those neurons might be dead.
Powell Palm has been working to find other methods of preserving organs. In a “landmark achievement,” he and his co-workers were able to successfully store and transplant supercooled kidneys from pigs.
He didn’t need cryoprotectants. Other teams are looking at chemical cocktail combinations that could allow organs to be stored for longer times, possibly by lowering the temperature. More on this here.
It is time to check up soon!)
A machine can be used to perfuse nutrients into an organ, simulating what occurs inside the human body. Over the past decade, machine perfusion devices are more common. They can maintain kidneys and livers for about 24 hours.
Scientists are adapting the protocol to a wide range of organs. This includes eyeballs.
A recent achievement that could enable full-eye transplants. In March I visited scientists in Valencia, who developed a system of perfusion for uteruses. The scientists had successfully used the device, which they called “Mother”, to keep a human-sized uterus alive.
Organ preservation is a very exciting field. Watch for additional coverage by MIT Technology Review In the next few weeks,
The Checkup published this article originally. MIT Technology Review’s Weekly biotech newsletter Receive it every Thursday and get articles such as this one first. Sign up for our newsletter .