We have all been familiar with pigs in our food but in the future, we could also be familiar with pigs as lifesavers
I remember one of the episodes in my old time favorite drama series, House, where the patient is told that she needs a new mitral valve. She is given two options, a plastic valve or a pig’s valve. She is stunned to hear the latter option. It’s kind of crazy to think that you might have to live with an animal’s organ as a replacement for your own, but did you know that in the US, as of March 2017 there are more than 118,000 names on the transplant list. More than 75,000 are actively waiting 8,365 organ transplants performed from less than 4,000 donors?
So, what are we going to do about the rest of thousands of them?
The advancement of biotechnology lately has opened a gate to the possibility of human-compatible animal organs. We have heard how CRISPR will impact the agriculture and other goods, and now scientists are using CRISPR to make animal organs compatible to temporarily replace failing organs in humans.
This is not the first time that animal to human transplants, also called xenotransplants, has crossed scientists’ minds. About 100 years ago, the first attempt of xenotransplantation was born, which eventually failed and had not been attempted again until 1963. First, it was Baboon organs, then it went on to include organ from chimpanzees and then pigs. Then in 1997, xenotransplants were banned until recently. It was due to the provirus called PERV (pig endogenous retrovirus) that every pig carries in their DNA. Some negative reactions to the ban resulted in studies which have shown that there is no evidence that PERV can be transmitted into humans. Although still banned from implementation, research on Xenotransplantation is already allowed again in some countries including the US and United Kingdom.
But you may be asking yourself, why pigs? when we’ve known that primates are the closest animals which have been linked to humans. The reason is because many primates are now considered endangered species, and there’s also a high risk of virus transmission. Pig organs come in all sizes and are similar to humans’. They are not categorized as endangered, they are easy to breed, and we consume the remainder of the animal, making pigs are more ethical than the primates. Furthermore, pigs are available for genetic engineering.
Taboo. The word that might pop up in many people’s heads but there are certainly benefits worth considering that might change their minds. Now let’s look at a few major reasons why xenotransplants are needed. Is it only a matter of saving lives? To be frank, it’s not.
- Decrease the number of people on the waiting list
This is the biggest motivation for researchers to go back to xenotransplantation. The numbers of people on US donor waiting list are already scary to look at, let alone the other countries’. Many of them on the list could die while waiting for donors to match. Xenotransplantation could avoid this issue by replacing the failing organ temporarily until the person gets a human donor. Organ demands are undeniably growing and we can keep up with the demand by using the latest technology to do something about it.
- Little evaluation on who should be the priorities
It’s a competition among patients to be put on the waiting list. Those who likely have longer life spans would be highly considered to be put further up on the list. So, when there’s a 40 year old person who needs a lung transplant just as much as a 70 year old, should we just demean the 70 year old by giving away the transplant to the 40 year old? More than just age, there are other things to evaluate in order to know if the valuable organs will make them become productive people. As quoted from organtransplants.org,
“Of course, debates about organ allocation will continue as long as there is such a large gap between patients who need transplants and the number of organs donated. Who, for example, should get priority, people who are the sickest or those who have the greatest chance of surviving and achieving a long life? And what is the significance, if any, of someone’s personal behavior? Should a much-needed heart go to a person who was a heavy smoker or a liver to someone who has suffered from alcoholism? These are difficult questions for which there are no easy answers.”
Everyone wants to get prioritized and none of us would want to demean another person’s life by any means, but there are always certain things that get in the way of someone to get their transplants. Looking at this, xenotransplantation could be a solution to make more, even all of those who are on the list to be prioritized.
- Xenotransplants could make black markets obsolete
As mentioned above, it’s not easy to get an organ while they are fighting to survive with the little that they have left. Others see it as an opportunity to trade organs for the big money. In the black market for organ donation, it’s not only about people who willingly sell their organs illegally, but black markets have opened a gate to human trafficking that happens mostly to children.
WHO has put an article about the dilemmas of human organ transplantation. Many people from developing countries sell their organs to make ends meet. Their problem isn’t solved right away. Living with one organ when there should be two needs continuous medical care including drugs and other treatments. The medical care they need costs more than their food. So, it is very often that these donors never get the medical care they need and that puts them in worse situations. Now you’re thinking, but don’t they get a large amount of money for the organs they give up?
To sell their organs, they can’t always meet the patients who will directly send the money to them. Thus, these donors have to sell their organs through agents who will get most of the money, leaving the donors with the least share. Also, we do not know the exact quality of the organs which many times have ended in failure not long after the transplantation. Xenotransplantation could end this illegal trade and also the crimes. Xenotransplants would have more trusted qualities because we could ensure the quality of the organs firsthand.
- Xenotransplants do not interfere with cultural beliefs in some countries
In China, dead bodies to be buried or cremated must remain intact. This cultural belief makes it hard for getting human donors. To aid this, China has been known to coercively use prisoners as donors. Having gained international worries, China claimed at a WHO conference last February that they have stopped organ harvesting practices as they have come to realize how unethical it was. However, in a country as big as China, it’s hard to discover everything, not to mention there’s no supporting data to prove the claim. Xenotransplantation should be happy news to the prisoners’ families because it could reduce the number of illicit activities that are still undiscovered across China and any other countries such as Egypt and Sri Lanka which still perform organ harvesting practices.
The opportunities above are substantial enough to support the eligibility of xenotransplants. We haven’t seen any of this happen yet, but CRISPR is a tool that could. It has given hope to xeno scientists to bring this trend back. There are biotechnologies companies which have stepped into this daring research. A few of them include United Therapeutics and eGenesis. Each company’s teams have indulged in trying out different combinations of genetic modifications using CRISPR. EGenesis, a biotech company founded by George Church, a Harvard scientist, raised $38 million in their series A funding, proving that using CRISPR has also led investors to see the bright future that waits ahead of the xenotransplant business. They also have released a paper about how eGenesis has successfully demonstrated a technique that can remove the virus and reduce the chance of virus transmission by using CRISPR/Cas9.
Making a business out of xenotransplantation is a challenging one, due to the risks and other obstacles that we have to solve before launching xenotransplant business. Here are the big issues that surround the process.
- Virus infection and human’s body hyperacute rejection
Pigs are known to naturally carry PERV (pig endogenous retrovirus) inside their DNA which takes us back to the year of 1997 when xenotransplantations were banned officially for this very reason. More than that, when another human being’s organ is replaced by organs from another human being, the recipient still has to take immunosuppressants in order to avoid rejections from the recipient’s body. Since we’re talking about putting an animal’s organ into a human’s body, there’s likely to still be a rejection from the human body that can cause infections. This issue is something that scientists have come to resolve by using gene-editing technology such as CRISPR. Hopefully using CRISPR and other gene-editing tools will help remove the cells in pigs that could cause hyperacute rejection and delete any cells that could transfer or spark infections in the recipient’s body.
- Animal Welfare
Even though using pigs is more ethical than primates, animal welfare groups do not see that it’s fair for the animals to be involved in xenotransplantation. They find gene-editing to be disturbing and bringing more harm to the animals due to the differentiation that makes the animals live unnatural lives. However, we can always offer animal protection through law and organizations to watch over how animals are treated in the labs. When we show them that there is no harm done during the process and most importantly, it’s a safe journey for all of us, we can expect full support that will enhance the possibility of this business growing larger.
- Pig donor’s price tags
We are talking about a variety of expensive prices when it comes to organ transplants. Imagine when someone has to give up their life because they cannot afford a transplant.
It is quite tricky to use that information as an opportunity to make xenotransplants affordable compared to human’s organs, as we are still uncertain how much it will cost. If we think about it, xenotransplants may need more preparations such as breeding, feeding, and other things to well-prepare the animals to be in healthy conditions. So, extra care may be needed to ensure the quality of the animals’ organs. The extra care indicates that xenotransplants could cost more than human’s organ transplant. If you could find ways to maintain the quality while at the same time not requiring the patients to spend more money, you are on your way to creating a multi-billion dollar business.
Overcoming the major issues listed above might take a long time. But let’s see it this way: Practice makes perfect. The time needed to complete the achievements you want to make from the research could reveal some other obstacles along the way which will bring you closer to an even better result.
It is clear how organ demand has exceeded the number of available supplies. By stepping into this type of business, xenotransplants could save 100,000 lives annually. Stephen Squinto told The Scientist that companies could first project their market focus on terminally ill patients who have no choice. Then if the animal’s organ is proved to offer a good quality of life, xenotransplants could become a treatment regimen which clearly will expand the market so that it’s not only viable to end-stage patients but to everyone on the list despite their stages and urgency.
We mentioned how in China, transplants came from prisoners. Such acts have raised awareness internationally for many years that China finally came to the solution that they would stop. So, once xenotransplants are acceptable, there’s certainly a big welcome from the prisoners, their families, and even the whole country of China, as we also don’t interfere with the local belief about the intact body burial/cremation. China itself is a big country with a very strong economy. The challenging business of xenotransplants could be huge in China alone and still grow its branches to the other countries.
Xenotransplantation has faced several failures before, but that has never weakened scientists’ motivation to continue doing their research. CRISPR lately has enabled scientists, investors, and entrepreneurs to see a brighter future for xenotransplantation. All the companies need to do is to prove successful xenotransplantation to defeat rumors and fear amongst people who are still skeptical. The rest of the countries will see how beneficial and more importantly, how safe xenotransplants are. It’s a slow-but-sure move that this type of business has to use in order to achieve the trust that will allow the xenotransplantation business breathe life to dying patients and also long life to the business itself.
Image from flickr by Hey Paul Studios