Surgeons in China have transplanted a genetically modified pig lung into a brain dead human recipient for the first time, with the organ functioning for nine days. The procedure, reported in Nature Medicine, represents the latest step in xenotransplantation, a field aiming to address the global shortage of donor organs. According to the World Health Organization, only around 10% of transplant needs worldwide are currently met.
The donor lung came from a Chinese Bama Xiang pig with six genetic modifications designed to reduce immune rejection. The lung remained viable for 216 hours and did not trigger immediate rejection or infection. However, signs of fluid buildup and damage appeared within 24 hours, and over time, antibodies progressively attacked the organ despite immunosuppressive treatment. Researchers noted that the recipient’s own remaining lung likely compensated for the pig lung’s decline.
Promise and Challenges Ahead
Experts described the study as a promising milestone but cautioned that lung xenotransplantation poses unique hurdles. Unlike other organs, lungs are constantly exposed to external environments, making them especially vulnerable to immune responses, infections, and pollution. “The immune system in the lung is very sensitive and active, which creates extra challenges for transplantation,” explained Professor Andrew Fisher of Newcastle University.
While xenotransplants of kidneys, hearts, and livers have shown limited survival in living patients, lungs remain particularly difficult. Researchers emphasized the need for further genetic engineering, refined immunosuppressive regimens, and improved preservation techniques. Other strategies under exploration include stem-cell-based regeneration of donor organs and reconditioning human lungs that were previously considered unsuitable for transplant.
Experts stress that although the breakthrough highlights progress, clinical application of pig lung transplants in living patients is still years away.
