It is controversial, it raises ethical debates, it causes many people to yell many times, but it is also remarkable: scientists of Salk Institute have successfully grown the first human-pig hybrid in the embryonic stage. Scientists hope the chimera embryos represent key steps toward life-saving lab-grown organs.
In a remarkable—if likely controversial—feat, scientists announced today that they have created the first successful human-animal hybrids. The project proves that human cells can be introduced into a non-human organism, survive, and even grow inside a host animal, in this case, pigs.
This biomedical advance has long been a dream and a quandary for scientists hoping to address a critical shortage of donor organs.
Every ten minutes, a person is added to the national waiting list for organ transplants. And every day, 22 people on that list die without the organ they need. What if, rather than relying on a generous donor, you could grow a custom organ inside an animal instead?
Around the world, shortage of organ donors is a serious cause of death that could maybe be avoided. This is the problem that the scientists under lead study author Jun Wu at Salk are seeking to tackle, by growing this hybrid.
The goal is to grow functional human organs within pig embryos, that will grow up to by hybrid species, and subsequently use them for the purposes of transplants.
The main problem towards this goal, after the team proving that human cells can be introduced in a non-human organism, and grow in it, is this: how would they make the given cells grow into the correct organs, tissues, and shapes?
The scientists introduced the cells into the embryos, and put the embryos in adult pig bodies, in order to let them grow for about 4 weeks, and then study them again.
The result was that the human cells had grown, but they weren’t enough in percentage. This would result in a human body rejecting organs grown in such organism, as they contain too much pig tissue.
Pigs were chosen as the hybrid animal because the way they grow and their organs are very similar to human.
The research needs to continue, but the results are already significant, and show that soon, such a hybrid will be successful and able to survive.
What will have in ethical terms, remains to be seen.
That’s now one step closer to reality, an international team of researchers led by the Salk Institute reports in the journal Cell. The team created what’s known scientifically as a chimera: an organism that contains cells from two different species.
In the past, human-animal chimeras have been beyond reach. Such experiments are currently ineligible for public funding in the United States (so far, the Salk team has relied on private donors for the chimera project).
Public opinion, too, has hampered the creation of organisms that are part human, part animal.
But for lead study author Jun Wu of the Salk Institute, we need only look to mythical chimeras—like the human-bird hybrids we know as angels—for a different perspective.
“In ancient civilizations, chimeras were associated with God,” he says, and our ancestors thought “the chimeric form can guard humans.” In a sense, that’s what the team hopes human-animal hybrids will one day do.