Chinese Scientists Successfully Transplant Pig Lung into Human

Chinese scientists have achieved a significant milestone by successfully transplanting a genetically engineered pig lung into a human for the first time. This groundbreaking experiment involved a brain-dead 39-year-old man who had suffered a brain haemorrhage. The procedure, part of ongoing research into xenotransplantation, opens new possibilities for addressing the critical shortage of human organs for transplantation.

The transplant was carried out by a team from Guangzhou Medical University, and the results were published in the journal Nature Medicine. The pig lung functioned effectively for nine days within the patient’s body, demonstrating viability without major rejection or infection. This is particularly noteworthy, as previous attempts at xenotransplantation have predominantly focused on organs such as hearts, livers, and kidneys, but the lungs pose unique challenges due to their delicate nature.

Beatriz Dominguez-Gil, director of the National Transplant Organisation in Spain, remarked on the significance of this achievement, stating, “This study marks a milestone in translational medicine: for the first time, a genetically modified pig lung has been implanted in a brain-dead human being.” She emphasized the complexities involved in lung transplantation, given that the lungs receive high blood flow and are constantly exposed to ambient air, making them particularly vulnerable to immune responses.

The research team explained that the pig lung had been genetically modified to deactivate six genes that trigger immune responses and to incorporate human genes that enhance compatibility and improve graft survival. While there were signs that the patient’s immune system began to react against the organ, leading to some lung damage, it was observed that these issues started to improve as the experiment progressed.

This development has sparked optimism about the future of organ transplantation. Current statistics indicate that in the UK alone, approximately 150 patients await lung transplants annually, with many succumbing to the wait due to a shortage of available organs. A significant portion of donated organs are unsuitable for transplantation, often due to rapid degradation after death or damage from illness.

Pigs are seen as ideal candidates for organ donation due to their size, rapid growth, and the fact they are already raised for human consumption. The advent of genetic editing tools such as CRISPR has propelled xenotransplantation research forward, allowing for precise modifications to the genetic code.

In March 2023, researchers from the Fourth Military Medical University in Xi’an, China, made headlines by implanting a genetically modified pig liver into a brain-dead patient, which survived for ten days. Similarly, American researchers have reported successful implantations of pig hearts and kidneys into humans.

Despite the promising nature of these studies, experts urge caution. Professor Ivan Fernandez Vega, coordinator of the Organoids hub of the ISCIII Biobanks and Biomodels platform, noted, “These studies reinforce that xenotransplantation is entering a clinical experimental phase with reproducible results in several organs.” He stressed that this particular study involved a single case, limiting the ability to generalize findings. The transplant was performed on a brain-dead patient, making it difficult to directly apply the results to living individuals.

The follow-up period was limited to nine days, leaving unanswered questions regarding the long-term viability of the graft and the potential for complications such as chronic rejection or late infections. As research in this area continues, the hope for viable alternatives to human organ transplantation remains a driving force for scientists and patients alike.