Breaking Boundaries in Organ Transplantation
We have entered a new era in organ transplantation, marked by a groundbreaking achievement in the field of xenotransplantation. Scientists have successfully transplanted a genetically modified pig liver into a human body, where it functioned for a short period. This pioneering feat was announced this week and published in a study in Nature.

A New Frontier in Xenotransplantation
Researchers in China have made this remarkable breakthrough, detailing their accomplishment in the study. The team transplanted the liver into a brain-dead recipient, where it survived and performed basic functions for over a week. This discovery suggests that animal-to-human transplantation, or xenotransplantation, may become a viable option for individuals in need of donated organs. Currently, over 100,000 Americans are on the waiting list for an organ, with a new person added every eight minutes. Unfortunately, only 48,000 transplants take place annually, resulting in a significant shortfall, with 17 people dying every day while waiting on the transplant list.

Addressing the Organ Shortage
Scientists have been exploring ways to extend the pool of available organs or to lengthen people’s survival while waiting for one. This includes the use of artificial devices or xenotransplantation. Recent advances in gene-editing technology have made it possible to create pigs with organs that are more compatible with human biology, reducing the chances of rejection. For instance, one common edit removes a pig’s ability to produce alpha-gal, a sugar that the human body doesn’t make.

Early Tests of Xenotransplantation
The researchers performed the procedure on a brain-dead recipient whose family agreed to participate. They transplanted a liver from a Bama miniature pig, which had six gene edits, while the recipient was given immune-suppressing drugs to prevent rejection. The team monitored both recipient and organ for 10 days, terminating the study at the family’s request. As with other early tests of xenotransplantation, the results are promising, with the liver remaining functional throughout the entire 10-day period.

A Successful Experiment
Things appeared to go smoothly during the experiment. The researchers found no signs of immediate rejection, and the liver began to produce bile within two hours of transplantation, maintaining acceptable blood flow. This achievement is a significant milestone, with the researchers noting that theirs is the first peer-reviewed study to document the bona fide transplantation of a gene-edited pig liver into a person. Last year, researchers at the University of Pennsylvania reported that they successfully attached a donor pig liver to a brain-dead recipient via a machine outside the body, keeping the organ alive for three days.

A Great Achievement
"It’s a great achievement," said study researcher Lin Wang at a press conference held on Tuesday. While we are still far from seeing pig-derived livers and other organs becoming commonplace, scientists have begun to transplant pig kidneys and hearts as a last resort treatment for otherwise terminally ill recipients. However, only two recipients are still alive, with 53-year-old Towana Looney currently being the longest-living recipient at roughly four months.

Future Prospects
Larger clinical trials are expected to start soon, but even if successful, outside scientists have cautioned that it may take a long time before animal-derived organs can approach the survivability of human donated organs. Nevertheless, xenotransplantation could become an important option even before that goal is achieved. The scientists note that the recipient’s own liver remained intact the entire time, suggesting that gene-edited pig organs could be used as a sort of bridging therapy for people on the transplant waiting list or for people whose organs need time to recover before becoming functional again.