Issues in Xenotransplantation

• Pigs are the animal of choice for xenotransplantation.pig image by Leonid Nyshko from Fotolia.com
  
  Xenotransplantation is the transplantation of an organ, tissue or cells between two different species; e.g., a transplant from a domestic swine to a human. This method of transplantation has been presented as a potential solution for the problem of human organ shortages. The general consensus is that genetically engineered pigs should be the source of organs for xenotransplantation.
  
  

Immunologic Rejection

• The primary medical issue with xenotransplantation is immunologic rejection. When a foreign organ or tissue is introduced to a recipient's immune system, the immune system attacks the organ or tissue. This can be managed by immunosuppressive therapy in the patients and genetic manipulations in the source animals, according to Boneva, Folks and Chapman. Such advances are making this issue less of a concern, but it is still an important obstacle.
  
  

Immunological Barriers

• Another issue the immune system presents is the crossing of species and immunological barriers, as reported by the Canadian Public Health Association (CPHA). This issue involves the risk of transmitting an infective agent to humans that may be passed on to others. A new and possibly highly infectious disease could be presented to the human race in this manner.
  
  

Ethical Issues

• The transplantation of animal organs into human bodies also raises ethical issues. According to the CPHA, such questions include "How far is it acceptable to interfere with nature in order to try to prolong human life?" and "Would crossing the species barrier have an impact on what it means to be human?" Such issues may need to be examined by society at large, the medical community and individual patients.
  
  

Animal Organ Donors

• To make the organ more viable, human genes are transplanted into the animal to decrease the chances of organ rejection by the human recipient. This raises ethical issues regarding the treatment of animals and whether or not we should be able to alter the genetic makeup of animals. Experimental procedures of any kind on animals are enough to raise issues with certain groups, such as People for the Ethical Treatment of Animals (PETA); genetically altering animals raises the issue to another level. CPHA reports that some argue that species boundaries protected immunologically are for the species' protection; tampering with these boundaries will have unpredictable repercussions.