Boston hospital transplants genetically modified pig kidney into a human for the first time in history

For about four hours on Saturday, five surgeons in a Boston operating room transplanted a genetically modified pig kidney into a living human. The news spread around the world five days later, when, this Thursday, Massachusetts General Hospital (MGH) finally announced the news. It is the first time in history that such a surgery has been "successful." The hospital can add this new accolade to its prestigious showcase which includes having performed the first successful human transplant in 1954 and the country's first penis transplant in 2016.

The patient, Richard Slayman, 62, had been diagnosed with end-stage renal disease. "I want to thank everyone at Mass General who has cared for me…They have supported me during every step of the journey, and I have faith they will continue to do so," Slayman, from Weymouth, Massachusetts, said in a statement shared by the hospital. He also said that when they explained what the treatment was like, he saw it "not only as a way to help (himself), but a way to provide hope for the thousands of people who need a transplant to survive."

The hospital explained that the procedure had been a "major milestone" in the search for ways to reduce the global organ shortage. Citing data from the United Network for Organ Sharing, they said that more than 100,000 Americans are waiting for a transplant - mostly kidneys. About 17 of them die every day.

The hope is that if doctors can use cells, tissues or organs from other species in humans, it could potentially eliminate the waiting list entirely. This process is called "xenotransplantation." In Slayman's case, a pig kidney with 69 genomic edits was used. Some harmful genes were eliminated from the pig to reduce the risk of rejection while others were added to human ones to increase compatibility.

The medical staff celebrated the results in style and Slayman is on the road to recovery. He has been able to walk the hills of the hospital since his surgery and his new kidney has already begun to produce urine. Doctors will continue to monitor the case closely. As in any transplant, there is a risk that the recipient's immune system may recognize the organ as foreign and potentially reject it. Unlike any other transplant, since there is nothing to compare it to, "We don’t know what the risk of rejection is."

They explained that the definitive success can only be truly celebrated if Slayman no longer requires additional dialysis, a treatment aimed at replacing the kidney's function to cleanse the blood.