The Facts and Fiction of Xenotransplantation
In 2021, New York University performed two cases of successful genetically modified pig kidney transplantation which brought people’s attention into the research area of Xenotransplantation. In this article, we are going deeper in the research history of Xenotransplantation. Then, further discuss what are the advantages and disadvantages for Xenotransplantation to solve the organ shortage in this century.
What is Xenotransplantation? (FDA)
Xenotransplantation contains transplantation, implantation or infusion procedures from nonhuman animals to human recipients. There are two broad categories
Live cells tissues or organs from nonhuman animal
Human body fluids, cells tissues or organs that have ex.vivo contact with live nonhuman animal cells, tissues or organs.
What is the difference between Allotransplantation and Xenotransplantation?
According to Nature, allotransplantation is transplantation of an organ or tissue from one same species with a different genotype. (For example human to human)
Xenotransplantation is transplantation of an organ or tissue from one species to the other with different genotypes. (For example pig to human)
Advantage of Xenotransplantation
Xenotransplantation has the advantage to solve neurodegenerative disease and diabetes which are commonly short of human donors. For example pig skin for man skin burns. Pig pancreatic islets for diabetes.
Why choose pig?
Instead of pigs, primates were commonly recognized as the species with the closest connection to humans. Why don't we use primate instead of pigs?
Primate is the species that scientists first intend to use. However, possible parallelism can occur during primate-human transplantation, such as HIV infection. HIV is possible to be transmitted from apes to humans.
Pigs have similar physiology and organ size to humans. Pigs are genetically engineered before performing organ transplantation. Pigs are genetically edited with deletion of Alpha 1,3 galactosyltransferase to prevent expression of antigens that the human body rejects.
Current xenotransplantation research overcome hyperacute rejection (destruction of transplanted organ with 24 hours)
Disadvantage of Xenotransplantation
Successful Xenotransplantation doesn’t mean a life long functional organ guarantee.
How to increase the long term survival rate after Xenotransplantation is a question we still need to do more research on.
Possible infectious disease from animals. This infection may be a new source that current technique cannot identify. Infection resources are also unknown which are less likely to prevent. The infection may also have potential risk of transfer to other humans.
Organ transplantation is definitely one of the most significant surgical technique developments in the 21st century. However, due to the limit of available organs, approximately 17 people die each day waiting for organ donations (data from Health Resource and Service Administration in 2021). Hopefully with the effort of ODAC (Organ donation associate cooperation), together we can clear the myth about organ transplantation. If you have any questions or to clear any myth about organ transplantation, contact us anytime.
Reference
https://www.organdonor.gov/learn/organ-donation-statistics
https://www.fda.gov/vaccines-blood-biologics/xenotransplantation
https://www.sciencedirect.com/science/article/pii/B9780123985231000690
https://www.sciencedirect.com/science/article/pii/B9780128046593000257