Back in 2017, scientists created the first human-pig hybrid by growing human cells inside early-stage pig embryos. They believe that their findings could eventually save hundreds of thousands of lives.
Every grand scientific discovery is accompanied by a certain amount of skepticism and criticism, but the boldest ones often trigger controversy and opposition as well.
One such lab creation, described as an interspecies chimera, led to mixed reactions, and many people questioning the ethical implications of it.
The word chimera comes from Greek mythology, and it depicted a monstrous, fire-breathing hybrid creature of Lycia in Asia Minor, composed of the parts of more than one animal.
There are two ways to create a chimera, either by introducing the organs of one animal into another or by introducing one animal’s cells into the embryo of another at the embryonic level and let them grow together into a hybrid.
Back in 2017, scientists in the US created the first pig-human hybrid in a lab, by growing human cells inside early-stage pig embryos.
They believe that the “breakthrough” could eventually save hundreds of thousands of lives, by creating lab-grown human organs that could be transplanted into people who need them.
After injecting human stem cells into early-stage pig embryos, the embryos were transferred into surrogate sows.
The researchers waited until the first trimester, and over 150 of them developed into chimeras, with the precursors of organs, including the heart and liver. Moreover, they also had a small number of human cells.
Team member Juan Carlos Izpisua Belmonte, from the Salk Institute in California, said:
“Our findings may offer hope for advancing science and medicine by providing an unprecedented ability to study early embryo development and organ formation, as well as a potential new avenue for medical therapies.
We have shown that a precisely targeted technology can allow an organism from one species to produce a specific organ composed of cells from another species.”
Izpisua Belmonte and his team have previously performed similar experiments as well, and back in 2015, they successfully integrated human stem cells into mouse embryos, and thus demonstrated that human stem cells can develop inside other species.
Regarding the pig-human hybrid, Belmonte said:
“The ultimate goal of chimeric research is to learn whether we can use stem-cell and gene-editing technologies to generate genetically-matched human tissues and organs, and we are very optimistic that continued work will lead to eventual success. But in the process, we are gaining a better understanding of species evolution as well as human embryogenesis and disease that is difficult to get in other ways.”
To prevent further ethical concerns, scientists terminated the hybrid embryos for the pig-human hybrid after 28 days of development.
Yet, proponents of the research argue that such experiments are important and justified, regarding the number of people dying daily while waiting for an organ transplant.
The members of the team discuss the results of their experiment in the video below: