Scientists at Guangzhou Medical University transferred a genetically modified pig lung into a brain-dead man, the team reported last week in Nature Medicine. Researchers have previously transferred the hearts and kidneys of genetically modified pigs into human patients with varying rates of success, but this is the first pig-to-human lung transplant.
The lung, which had six edited genes, was transplanted into a brain-dead 39-year-old man. Although the organ sustained some damage in the procedure, it still exhibited partial function once transplanted. Only the left lung was transplanted, so the question of whether the lung could sustain life on its own remains unknown.
Another person is added to the waiting list every 8 minutes. Data from: https://data.hrsa.gov/topics/health-systems/organ-donation
Three days after transplantation, the scientists observed signs of antibody-mediated rejection, the most common cause of transplant rejection. There was also fluid buildup in the lung. The organ was removed after nine days. The lung continued functioning for the entire observation period and showed partial recovery from rejection on day nine.
The organ transplant problem
Lungs are rich in immune cells and have aggressive immune responses, which is why lung transplants are more likely to fail compared to other solid organ transplants. Additionally, in human-to-human transplants, lungs only last five to seven years, compared with 12 to 14 years for a kidney transplant. Only about half of patients are still alive five years after a lung transplant, according to Mayo Clinic.
According to the Health Resources and Services Administration, 103,223 patients are on the national transplant waiting list, with another person added every eight minutes. There were 70,634 waitlist candidates in 2024, and only 24,019 donors (both deceased and living). Many hope that being able to source organs from genetically modified animals can help close this gap.
Both human and animal organ research approaches gaining steam
In addition to genetically modified pig organs, there have also been advancements towards growing human organs in mice and pig embryos. Human hearts were able to survive inside pig embryos for 21 days, and even started beating.
The China lung experiment follows a series of pig-to-human transplants. Massachusetts General Hospital performed the world’s first successful transplant of a genetically-edited pig kidney into a 62-year-old man in March 2024, though the patient passed away two months later due to an “unexpected cardiac event” that his doctors said was unrelated to the transplant. NYU Langone transplanted a pig kidney into Towana Looney in November 2024, who became the longest-surviving recipient of a pig organ, with the kidney still functioning well after more than two months. On February 3, 2025, the FDA cleared United Therapeutics’ IND for the first clinical trial of a gene-edited pig kidney (UKidney), starting with six patients and aiming to perform the first transplant around mid-2025.
