Pig cell transplants raise ethical issues, such as whether it is right to use animals to benefit humans and what impact an individual’s right to treatment may have on the wider community.
Meeting a human need
There is a worldwide shortage of donated human cells, tissues and organs to meet the needs of people with life-threatening diseases. Xenotransplantation, or animal to human transplantation, could provide a solution. At Living Cell Technologies (LCT) in New Zealand, they are developing pig cell transplants to treat type 1 diabetes, Parkinson’s disease, Huntingdon’s disease, stroke and hearing loss. Read this article Xenotransplantation and organ donation to find out more.
Pig cell transplants and ethical issues
Using animals to benefit humans raises ethical issues. People’s views on pig cell transplants are likely to be influenced by:
- knowing someone with a medical condition who may benefit
- understanding the benefits and risks of the technology
- views on the rights and welfare of animals
- cultural, spiritual or religious views.
Weighing benefits and risks
Governments and health regulators need to look at the consequences of any new medical technology. This involves weighing the benefits and risks and is a common framework for ethical analysis.
Benefits of pig cell transplants for type 1 diabetes
Type 1 diabetes affects about 25,000 people in New Zealand and more than 40 million people worldwide. People with type 1 diabetes monitor their blood sugar and inject insulin every day to live. The disease has severe consequences on lifestyle, health and wellbeing and can shorten life expectancy. Treatment of type 1 diabetes and associated health complications is expensive (about NZ$1 million for the lifetime of a patient).
LCT is developing pig cell transplants to treat type 1 diabetes. The benefits for type 1 diabetics include better control of their blood sugar levels leading to an improved quality of life, fewer health complications and a longer life expectancy. This treatment may also mean that diabetics need fewer or no insulin injections. Pig cell transplants are expensive but likely to save money by reducing health complications and insulin injections for diabetics.
Risks of pig cell transplants for type 1 diabetes
The main risk of pig cell transplants is the transmission of known (or unknown) disease-causing pathogens, such as viruses and bacteria, to the transplant recipient. Porcine endogenous retrovirus (PERV) is found in the DNA of all pigs. it’s an inactive provirus that could potentially release an infectious viral particle. The risk of PERV transmission is low, but its presence in all pigs’ DNA has caused concern for xenotransplants. PERV has never infected a pig transplant recipient, but it has the potential to do so. LCT minimises the risk of disease transmission by using cells from pigs that have low amounts of PERV, that are designated pathogen-free and that are housed in a barrier facility. They also test the pigs and pig cell products before transplantation to ensure they remain pathogen-free. This article, Designated pathogen-free pigs – origins and welfare has further information.
Potential porcine endogenous retrovirus activation
Porcine endogenous retrovirus (PERV) is a retrovirus found in the DNA of all pigs. The virus is normally in an inactive proviral form, but can potentially produce mature viral particles infectious for other species. PERV infection is a risk of pig to human transplants.
Public risk and individual rights
An individual with type 1 diabetes must understand all the benefits and risks of a pig cell transplant and give informed consent prior to transplantation. A pig cell transplant is unusual because it has the potential to place the wider community at risk – a new disease could spread from the recipient to the wider community. LCT manages this risk by using designated pathogen-free pigs and monitoring all pig cell recipients for disease up to 2 years after they receive a transplant. Some people believe in tougher restrictions, stricter monitoring and travel restrictions, but these will all restrict an individual’s rights to confidentiality and freedom. Do you think the risk justifies more strict controls?
Animal welfare and ethics
Almost everyone believes that it is wrong to hurt or kill animals. Pig cell transplants involve raising pigs inside a pathogen-free barrier facility and killing piglets under anaesthesia. Is this acceptable because it has significant health and life expectancy benefits for type 1 diabetics? For some people, using pigs raises fewer ethical concerns because they are already reared and killed for meat. You may believe that the human benefit from this technology justifies the use of pigs, whereas other people may not.
Cultural, spiritual and religious views
Peoples’ views on pig cell transplants will be influenced by their cultural, spiritual and religious backgrounds. In general, most religions find xenotransplantation acceptable. Faiths such as Islam and Judaism, for example, forbid the eating of pork but still accept pig transplants that are for human benefit as long as animals are treated with respect. But even within groups, there may be a range of opinions or beliefs, and these may change over time as the benefits of a new technology become apparent. Some people may object to pig cell transplants as fundamentally wrong, unnatural or ‘playing God’. What do you think?
Useful links
A panel of experts on xenotransplantation discusses xenotransplantation and LCT trials in New Zealand in 2009. See this Science Media Centre article, which includes links to audio files.
Keep up to date with the latest developments on the Algorae Pharmaceuticals Ltd website. In 2023 LCT changed it's name to Algorae Pharmaceuticals Ltd.
