A genetically engineered pig kidney transplanted into a brain dead man continues to function after 32 days–marking the longest time such a kidney has worked in a human being and another milestone in the emerging field of xenotransplantation (the transplanting of organs from one species to another).
The success of the procedure offers a lot of hope for the growing backlog of more than 103,000 U.S. patients on the organ transplant list–with the vast majority (88,000) waiting for kidneys. The average wait time for kidney recipients is three to five year depending on the condition of each patient.
The new procedure was performed on July 14, 2023 by a team of doctors at NYU Langone Health on a 57-year-old patient named Maurice Miller who passed unexpectedly following surgery to investigate a brain tumor. Miller is neurologically dead but continues to survive with a heartbeat and ventilator. Since the transplant, the pig’s kidney has worked perfectly. It even started producing urine shortly after the operation.
“The kidney of a pig appears to perform all the functions that a human kidney would normally do,” Robert Montgomery said Wednesday. Montgomery is renowned professor of surgery at NYU Langone Transplant Institute and the director of their Transplant Institute.
Montgomery also performed the first genetically-modified pig kidney transplant in September 2021 followed by another transplant in November 2021. In the year following, his colleagues from NYU Langone performed 2 pig heart transplants ..
Unlike the previous kidney procedures though, which lasted no more than a few days, this most recent xenotransplantation has lasted more than a month–and doctors expect it will continue to function well for even longer.
Montgomery noted that pig kidneys “required less genetic manipulation to be accepted by the human immune system than a pig heart.” To modify the organ for human transplantation, the NYU Langone team had to remove a gene that encodes a molecule called alpha-gal, which triggers the immune system response that leads to a rejection of foreign proteins from the human body. The team also embedded the pig’s thymus gland into the kidney, which they say was capable of “educating” the human immune system so it would not perceive the new organ as a threat.
Previous xenotransplantation organs have required as many as 10 genetic modifications. The new transplantation only required a knockout of a single gene to make it function properly in the patient. This was a much easier procedure.
The transplant patient’s kidneys were both removed before the pig kidney was transplanted. The kidney was monitored and–at the end of the first month–biopsied. Montgomery said that the kidney showed “normal renal functions in clearing of toxins” and no sign of rejection.
This research, while incredibly promising is in its early stages. Important to remember that the gene-hacked organ has not yet been transplanted into a brain dead patient. Many more studies and trials need to be run before we can see a large-scale roll out of xenotransplantations.
But, the success of this new procedure could be a blueprint to make xenotransplantation simpler and save thousands of life each year.
For now, the team will continue to monitor the transplant patient for another month.
“We’ll know at the end two months if the transplant patient is at risk of chronic rejection. Montgomery explained. “I think we’ll have a good view into that with our biopsies and tissue we’ll be able to look at at the end of two months.”
The post A Gene-Hacked Pig Kidney Has Worked in a Brain Dead Human for a Month appeared first on The Daily Beast.
