Answering some `pigs for parts’ concerns

Elton Wong

Have you heard about the new lines of pigs that have been specially developed to donate their organs to people? It’s an interesting development.

For instance, after you get a new liver, you get to have some barbecued ribs. And the best part is that they taste just like human ribs.

No, actually that’s just what I told my impressionable young sister to freak her out. The part about the pigs is true though.

A company called Infigen has recently engineered a line of pigs that could one day be used as sources of organs for transplant. Scientists jokingly call this the “pigs for parts” project.

Organ transplantation has always been a tricky business.

The human immune system, which protects us against bacteria and viruses, is very good at recognizing what is foreign to our bodies.

Normally, this system works very well.

As a result, foreign blood or organs introduced into a person’s body must be screened to make sure they closely match the blood or tissue type of the recipient.

The molecular basis for tissue-typing and immune response are antigens, molecules present on the surface of cells.

The cells in your body all have a certain kind of antigen that your immune system recognizes and leaves alone. If your white blood cells run into cells that don’t show the proper antigens, those cells are destroyed.

Human organs have always worked the best for transplant because genetic similarities between humans make for antigen similarities.

However, that may change. The newly engineered pigs have been genetically altered so that their cells display antigens that are more human-like.

As the technology improves, scientists may be able to create pigs with very specific antigen profiles, custom-made for specific recipients.

Already, xenotransplantation shows promise. Early trials show that fetal neurons from pigs are just as good as fetal human neurons in treating neurological disorders in humans.

A stroke victim named Amanda Davis was once paralyzed on the left side of her body but can now run and has regained use of her left arm, thanks to transplanted neurons from fetal pigs.

Diseases from Parkinson’s to Huntington’s, as well as epilepsy and spinal cord injury could one day be treatable through these methods.

As has always been the case, these biotechnological advances have opened a host of questions.

Here are a few such questions, and a few words on them.

Is xenotransplantation unnatural/against the will of the Lord?

People always use this one. On the face of it, yes, it does seem a little weird to transplant organs from pigs to people.

But if you want to take that angle, medicine can be seen as a whole body of unnatural acts.

From Tylenol to antibiotics to angioplasty, medicine is the opposite of “letting nature run its course,” whatever that phrase is supposed to mean.

There are religious groups that don’t partake in medicine, and that is of course their right, unless they endanger the lives of their children, who are too young to make that choice.

No one will be forced to accept organs from pigs, just as no one is forced to receive transplants now, even to save their life.

But this year alone, 53,000 of 75,000 patients waiting for organs will die before getting them. The sentiment that xenotransplantation is “unnatural” should not keep these patients from getting organs and living.

Does xenotransplantation violate animal rights?

The animal rights activists don’t like the idea of animals being used for their organs.

This is to be expected since these same activists have been against all kinds of animal experimentation all along and against animal agriculture, too.

The fact is since most people see nothing wrong with killing pigs for food, they are unlikely to have a problem with pigs dying to save human lives.

Even the most ardent activists will have trouble arguing that it is better to let thousands of people die than to harvest organs from pigs.

The problem is that nature is more cruel to animals than humans are, and if we really respected animal rights, we’d have to stop lions from eating zebras and wolves from eating caribou.

No animal rights activists advocate rounding up wolves and forcing them to subsist on veggieburgers.

Inconsistencies like these make it hard to adopt animal-rights arguments, especially when the benefit to humans is so clear in this case.

All I can say to animal rights people is that I’ve read Peter Singer’s “Animal Liberation,” too, and it almost convinced me, but not quite.

What health problems could be caused by xenotransplantation?

Ah, here’s where it gets interesting. Many human diseases originate from animals.

The HIV virus, for example, comes from a similar virus found in monkeys, where it does little damage. Once the virus crossed over to people, however, it became one of the deadliest of known diseases.

As scientists do not have absolute knowledge of the viruses that a pig might be carrying at any given time (harmless viruses are hard to detect), there are no guarantees that the next AIDS won’t transfer to humans through xenotransplantation.

Then again, nothing of the sort might happen.

Given this possibility, it makes little sense to halt research in this promising field. Like many medical technologies, xenotransplantation presents both promises and risks.

Prudent regulation and cautionary measures can help maximize the former while minimizing the latter.

Like all technological breakthroughs, xenotransplantation will be evaluated more reasonably after all the sensationalism surrounding it has died down.

Elton Wong is a senior in genetics and philosophy from Ames.