Surgeons in China have successfully transplanted a genetically modified pig lung into a brain-dead human recipient, where it remained functional for nine days. The procedure, reported in Nature Medicine, represents a major milestone in xenotransplantation—a field aimed at addressing the global shortage of donor organs. According to the World Health Organization, only around 10% of the worldwide need for transplants is currently being met.
The lung, taken from a Chinese Bama Xiang pig with six genetic modifications, was implanted into a 39-year-old male recipient. Researchers found that the organ functioned over a 216-hour period without triggering hyperacute rejection or infection. However, fluid buildup and progressive antibody-mediated damage occurred despite strong immunosuppressive treatment, highlighting the challenges that remain.
Challenges of Lung Xenotransplantation
Experts caution that the experiment is a preliminary step. Lungs are particularly difficult to transplant because they are constantly exposed to environmental pathogens and pollutants, making them more susceptible to immune responses. Andrew Fisher, a professor of respiratory transplant medicine at Newcastle University, noted that the presence of the recipient’s other lung may have masked the extent of the pig lung’s damage.
Brain death itself can complicate results, as it induces acute inflammation, said Peter Friend of the University of Oxford. Researchers stress that further work is needed to refine genetic modifications, optimize immunosuppressive regimens, and improve long-term lung preservation.
Future Directions
While xenotransplantation has advanced with organs such as kidneys, hearts, and livers, lungs present unique hurdles. Researchers are also exploring alternative approaches, including:
- Remodeling human donor lungs previously deemed unsuitable for transplantation.
- Growing humanized organs in pigs or sheep using stem cells.
Fisher believes that improving the usability of human donor lungs could offer a faster, practical solution, potentially making a significant impact within years, while xenotransplantation continues to be developed.
This achievement marks a step forward, but experts emphasize that widespread clinical use of pig lungs is still a long way off.
