A 71-year-old man became the first living person to receive a liver transplant from a genetically modified pig, as reported in the journal Nature in the form of news on May 31, 2024. The procedure was performed by a team of surgeons at the First Affiliated Hospital of Anhui Medical University in China. This case presents a breakthrough in the field of xenotransplantation, offering hope for thousands of patients on organ transplant waiting lists. However, it also raises considerations about biosafety and bioethics.

Biosafety Considerations

The genetically modified pig liver used in the transplant underwent ten genetic modifications, including the deactivation of three genes that produce sugars on the surface of pig cells and the introduction of seven genes that express human proteins, to prevent rejection by the recipient’s immune system. However, the long-term effects of genetically modified pig liver transplants on human recipients remain largely unknown. There are unforeseeable potential risks due to genetic incompatibility or the development of new diseases, including long-term changes in the immune system’s response and unexpected biological reactions triggered by genetic modifications. Additionally, genetically modified organs may interact in complex ways with human physiological systems, which is not yet fully understood.

Moreover, the production and use of genetically modified pigs for transplantation could inadvertently impact non-target species and ecosystems. Gene transfer between modified pigs and wild populations could disrupt natural biodiversity, leading to ecological imbalances. Additionally, the spread of transgenes through environmental exposure poses a risk to other species, potentially creating new challenges to biosafety management.

Bioethics Considerations

The ethical implications of genetic modification extend far beyond biosafety considerations, particularly regarding animal welfare. The production of genetically modified pigs for organ transplants involves complex biotechnological procedures that may affect their health and well-being. The modification to make pig organs compatible with the human immune system may lead to potential pain and health issues for them. For instance, these pigs might experience altered growth patterns, immune deficiencies, or other health complications that compromise their quality of life.

Balancing animal welfare with human health benefits presents a complex ethical dilemma. While the potential for genetically modified organs to save human lives is immense, the ethical implications of this practice cannot be overlooked. Using genetically modified animals for transplants may lead to significant medical breakthroughs, but it also raises concerns about the violation of animal rights. This balance requires a thoughtful approach that respects both human and animal lives, ensuring that human health benefits are not achieved at an unacceptable moral cost.

This reported successful transplant case paves the way for future xenotransplantation, offering the potential to alleviate the organ shortage crisis and providing valuable insights and hope for future organ transplants. However, it is imperative to continue addressing the biosafety and bioethical challenges associated with xenotransplantation to ensure its safe and ethical implementation.

For more detailed information and insights on successful pig liver transplantation to humans, refer to the full paper by Smriti Mallapaty, published in Nature: First pig-to-human liver transplant recipient ‘doing very well’.

References

Mallapaty S., First Pig-to-Human Liver Transplant Recipient ‘Doing Very Well’. Nature (2024). doi: https://doi.org/10.1038/d41586-024-01613-4