Doctors perform experimental pig kidney xenograft on human

The kidney is one of the organs most often transplanted by doctors. In 2022, 3,376 people underwent kidney transplant. ReinRein Out of a total of 5,494 transplant recipients in France, all organs combined. Despite everything, this is not enough to meet the demand for kidney transplants and it is estimated that 40% of people on the waiting list are actually transplanted between one and three years after their registration; After waiting for five years it is 15%.

Some scientists are working to deal with the lack of this organ. xenograffesxenograffesTransplantation of an organ of animal origin into a human. In October 2021, US doctors performed the first xenograft of a pig kidney on a human. Today, doctors at the University of Alabama have repeated the experiment and published the details. jama surgery,

a successful xenograft

condition of a 50-year-old man brain deathbrain deathwas transplanted with two genetically modified pig kidneys, on which 10 GenoaGenoa Stayed To end Or knock down To make them more compatible with the human body and limit the risk of rejection. After xenograft, pig kidney produced several liters of urine and managed to filter it creatinecreatineAnd wastewaste Metabolism produced by muscles. These two parameters indicate that both the transplanted kidneys perform their functions perfectly.

At the moment, successful kidney xenografts can be counted on the fingers of one hand and it is not yet certain that they are safe and effective for the general population and can be performed as easily as conventional transplants.

World’s first xenograft of pig kidney on human

Article published by Celine Delujarche on October 24, 2021

It has happened for the first time in the world: genetically modified pig kidneys functioned normally without causing rejection in an experiment on humans. One step closer to xenografts, a longtime dream for doctors who hope to answer organ shortages in this way.

A pig kidney was transplanted to a recently deceased patient whose family had given consent. The kidney managed to function for three days, perfectly performing its functions of filtering and producing urine, and without causing rejection, on October 20. Professor Robert Montgomery’s team at Center Langone Health in New York underwent the operation. announced to execute.

Kidney was taken from a pig genetically modified to eliminate the gene that produces alphagal Sucresucre not present in humans and which usually causes transplant rejectiontransplant rejection Animal. Manufactured by United Therapeutics, this pig was approved in December 2020 Food and Drug Administration ,FDAFDA, For three days the kidney was attached to blood vessels and kept in a working condition outside the body. , rate of creatininecreatinine The patient returned to his normal level immediately after the transplant, which shows that the kidney is doing its job well.Professor Robert Montgomery says. It gave even better results than some human kidneys from dead people. ,

Twelve people die every day waiting for a kidney in the United States

, More than half of dialysis patients deteriorate rapidly or die before transplant says Robert Montgomery, who recently had a heart transplant. , I know what it’s like to be unsure when an organ will be available “. In the United States, there are 90,000 people waiting for a kidney transplant and twelve people die every day because of a lack of a timely kidney transplant. This experiment could lead to actual transplants in patients with advanced kidney disease. within a year or two », Evans Robert Montgomery.

40 years of progress in xenografts

Xenografts (transplantation between). speciesspecies different) is an old dream of doctors, who hope to breed animals as “organ reserves”. The first real test took place in 1984, where a baby boy nicknamed “Baby Fay” lived for 21 days with a baboon’s heart. Since then, research has evolved and doctors have focused more on pork; The reproduction of the latter is easier, with rapid growth and limbs of a similar size to humans. Furthermore, its use as a “reservoir” raises fewer ethical questions than primatesprimates For example.

heart valves, tendons, pieces of skin or retinaretina Pork is already used as a temporary or permanent graft in humans. But today’s operation shows that whole organs can be transplanted successfully, which could pave the way for other types of transplants. In 2018, a baboon survived for six months with a pig’s heart.

However, there are still many uncertainties about this technology (the details of which have not yet been published). First it will be necessary to make sure that the graft is viable DurationDuration, Some also fear that xenografts may promote the transmission of the virus from pigs to humans. But, for Robert Montgomery, the risk is less than letting patients die while waiting for transplants or watching their health deteriorate rapidly.

Article published by Edit BE Germany on 08/16/2005

Transplantation is the only means of survival for many incurable organ diseases. However, there are not enough organ donors worldwide. An alternative is xenografting, ie the use of animal organs and tissues to engraft human patients.

For all transplants, but especially for this type of transplant, immune reactions must be feared. “Pig organ transplant in primates triggers a complex cascade of rejection mechanisms”, Report Prof. Dr Wolf, “We can overcome this phenomenon in the long term only by revising geneticgenetic donor pigs.

The team of Professors Dr. Eckhard Wolf and Dr. Regina Klose in Munich managed to breed a genetically modified TRAIL pig, whose organs are the primary defense for human immune protection. This TRAIL has the human protein “TNF alpha-related apoptosis-inducing ligand” as a marker on the surface of pig cells. thus they are protected from cells in vitro immune systemimmune system human being. Further studies will be needed to show whether this mechanism also works in living animals. This would of course require a combination of different genetic modifications of the donor pigs.