What is Xenotransplantation?
- Xenotransplantation refers to the transplantation, implantation, or infusion of live cells, tissues, or organs from animals into a human recipient.
- It can also involve human cells, tissues, or organs that have had prior ex vivo (outside the body) contact with non-human animal cells or tissues.
- First attempts at xenotransplantation involving the human heart were made in the 1980s.
- Genetic modifications are required in animal organs to prevent immune rejection by the human body.
- Post-transplantation monitoring is crucial to ensure organ functionality and detect immune responses.
Why Are Pigs Used for Xenotransplantation?
- Pig heart valves have been successfully used for human valve replacements for over 50 years.
- Anatomical and physiological similarities between pigs and humans make pigs ideal organ donors.
- Pigs are widely farmed, making organ availability cost-effective and scalable.
- The variety of pig breeds allows organ size to be matched with specific human requirements.
Recent Advancements in Xenotransplantation
- First Genetically Modified Pig Heart Transplant (2022): A genetically modified pig heart was successfully transplanted into a human for the first time.
- The experiment demonstrated the potential of genetically modified pig organs for human transplantation.
- Gene-Modified Pig Liver Transplantation (2025): Chinese researchers from the Fourth Military Medical University, Xi’an successfully transplanted a gene-edited pig liver into a brain-dead human recipient.
- Key Genetic Modifications:
- Six genes are edited to prevent immune rejection.
- Human transgenes are inserted to enhance compatibility.
- Observations Over 10 Days:
- The pig liver produced bile and albumin, indicating basic functionality.
- Stable blood flow was maintained.
- No signs of rejection were observed due to immunosuppressants.
- The study was published in Nature.
- Potential Use: Gene-modified pig livers could serve as a "bridge therapy" for patients awaiting human organ transplants.
- However, long-term viability and full liver functionality remain uncertain.
