Written by by Kitra Cahana, CNN
Dutch scientists have developed a pig kidney transplant system that is almost as effective as human.
Writing in an article published in the journal Nature Methods , a team of researchers describe a new method that bypasses the medical procedures used in human kidney transplants.
The process involves the pig kidney transplant being planted into a ‘spoon-like’ artificial bile duct, which joins the patient’s circulatory system to the donor’s.
“The process is remarkably quick, and it’s completely transparent and sterile,” Amro Haddad, a professor at the Odense Medical School in Denmark, told CNN.
The raw material for the new organ comes from a donation of a pig kidney, taken from a pig farmer.
After the pig kidney has been transplanted into the spoon, it is then introduced to the donor’s bile duct, using a biologic method to hook it up to the recipient’s own blood vessels.
“The entire organ transplant system is totally compatible and in human terms comparable to transplantations when using human organs, but we can have a bile duct made of pig organs. In comparison to transplantation procedures, this is much, much faster,” Haddad told CNN.
“For example, in Morocco, a husband and wife would be together, a wife receives the transplant, and the husband is immediately with her in hospital. The whole process takes 24 hours. When we are comparing ourselves with that, it is almost overnight. The effect of being completely transparent and sterile means that the transplant is much, much faster.”
The surgery is then performed by a member of the hospital staff, and essentially resembles a mini-operation, with the patient waking up a day or two later with all that they’ve lost, replaced with a freshly-transplanted kidney.
‘See and scratch’
“The (human) organ is replaced by a pig organ, the surgeon draws two tubes and feeds them down. Then it’s a cheater test. There’s no organ at the side of the brain, because what we need is the organ in its entirety. And it’s a huge operation,” Haddad said.
“Once you start to remove the tissue, but also the blood vessels, it’s quite difficult. So if you just remove the spine it’s already a done deal. In theory, it’s just a matter of once you have re-implantation, all the kidney will make it.
“In the pig case, we didn’t get any adverse reaction from the patient because the organ is fully hydrated. The liver is there. The blood supply is there. So there’s no substance in the body that’s going to die. The pig organs don’t have all the ill effects. It’s the sugar that dies that kills the patient. But that protein called the K2, is fully intact in the pig vessels, and we now know that once the recipient’s existing cells are transplanted into the transplanted organs, they essentially learn to see and scratch.”
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The graft of the foreign organ is then wound with stitches and implanted in a patient’s body. The inserted pig kidney is also exposed to immune warfare, leaving the recipient vulnerable to a host of bacteria.
By contrast, the sperm in a human semen donation is not touched. It passes through the body without being touched, while the zygote of sperm that fertilizes the egg inside the woman’s womb is infected with the human germ cell.
After a trial involving a woman who died suddenly of a heart attack in 2015, the Dutch team is now testing a similar method on a 60-year-old woman, who is undergoing brain stem injury rehabilitation in a coma.
“By practicing brain stem injury rehabilitation with the ‘impulse generator,’ we demonstrated that the patient can initially tolerate the bile duct formation without immune problems,” said Moira Busch, a doctor from the Odense Medical School in Denmark, who co-authored the paper with Haddad.
The team says they are interested in pursuing such clinical trials on children.