New Delhi, 26 August 2025: In a groundbreaking leap in transplant medicine, Chinese surgeons have performed the world’s first pig-to-human lung transplant using a genetically modified pig lung. The recipient, a brain-dead patient, sustained lung function for nine days, marking a major scientific milestone in the emerging field of xenotransplantation.
The Historic Procedure
In May 2024, a team of surgeons in China carried out the pioneering surgery on a 39-year-old man who had been declared brain-dead following a hemorrhagic stroke. With consent from the patient’s family, doctors replaced his left lung with a pig lung that had been genetically engineered to reduce the risk of immune rejection. His right lung, which remained human, served as a control.
The donor pig had undergone six genetic modifications. Scientists removed three pig genes responsible for producing sugar molecules known to trigger human immune attacks. Additionally, three human genes were inserted to help the pig lung function more compatibly in a human body by regulating immune response and reducing clotting.
This operation represented the first time a pig lung had ever been transplanted into a human, even in an experimental setting.
Early Success and Emerging Complications
Within the first 24 hours post-surgery, the pig lung showed no signs of hyperacute rejection—an immediate and severe immune response that typically leads to failure in cross-species transplants. The lung was oxygenating blood effectively and performing basic respiratory functions as hoped.
However, challenges began to surface by day two, when doctors observed fluid accumulation in the lung. This was likely a result of ischemia–reperfusion injury, a common complication in transplants where blood flow restoration causes inflammation and damage. As the days progressed, signs of immune rejection became more apparent. By day six, there were markers of antibody-mediated rejection, indicating the body was starting to mount a stronger immune attack against the foreign organ.
Interestingly, by day nine, researchers noted a partial recovery in lung function. The lung showed signs of adaptation, suggesting that while rejection processes were underway, the organ had not completely failed. The experiment concluded on the ninth day at the request of the patient’s family.
Scientific Significance
The success of this experiment, even for just nine days, is considered a major achievement. It is the first evidence that a genetically modified pig lung can sustain function within a human body—without immediate destruction by the immune system. While previous experiments with pig kidneys and hearts in humans and primates had shown promise, lungs have posed a greater challenge due to their constant exposure to airborne pathogens and environmental triggers.
Lungs are also notoriously fragile and prone to rejection due to their large surface area and complex vascular system. This makes the successful short-term function of the transplanted pig lung even more impressive, and a significant proof of concept.
Experts in the field have expressed cautious optimism. The procedure demonstrated the technical feasibility of lung xenotransplantation and laid the foundation for future studies that could one day make animal-to-human lung transplants a reality for living patients.
Limitations and Future Directions
While the results are encouraging, researchers emphasize that this is still an early-stage experiment. The patient was brain-dead, meaning the body’s immune and inflammatory responses could differ from those of a living person. It is still unclear how a living patient would respond to a pig lung over a longer period, or whether the immune system could be adequately controlled without compromising safety.
The next steps for the research team include refining genetic modifications in donor pigs, improving immunosuppressive protocols, and enhancing organ preservation methods. Scientists are also looking into the feasibility of transplanting both lungs and conducting longer-term trials with extended observation periods.
Further studies will also need to explore whether these organs can perform well enough over time to meet the rigorous demands of human physiology, especially in patients with severe lung disease.
A Glimmer of Hope Amid Organ Shortages
Globally, thousands of patients die every year waiting for organ transplants, especially lungs, which are among the scarcest and most difficult to match. In this context, xenotransplantation—using organs from animals—offers a potential game-changer.
Genetically engineered pigs have emerged as the leading candidates for this approach, and this experiment could be the first in a new wave of life-saving innovations. If scientists can overcome the hurdles of immune rejection and long-term functionality, pig organs might one day help eliminate transplant waiting lists altogether.
The successful short-term survival of a pig lung in a human body marks a monumental step forward in transplant medicine. While clinical application in living patients remains years away, this achievement opens new pathways to address the urgent global need for donor organs. With continued research, ethical oversight, and technological refinement, xenotransplantation may soon transition from science fiction to standard medical practice.
