Human cells grown in monkey embryos raise ethical concerns about Pandora’s box from Science & Tech News
Human cells were grown in monkey embryos by scientists in the United States, raising ethical concerns and warnings that they were “opening a Pandora’s box”.
Those behind the research say their work could help address the serious shortage of transplant organs and provide a better overall understanding of human health, from disease development to aging.
However, some experts in the UK have highlighted the significant ethical and legal challenges posed by the creation of such hybrid organisms and called for public debate.
Concerns arose after researchers at the Salk Institute in California created what are known as monkey-human chimeras.
Human stem cells – special cells that can develop into many different cell types – were introduced into macaque embryos in petri dishes in the laboratory.
The aim is to understand more about how cells develop and communicate with one another.
Chimeras are organisms whose cells are derived from two or more individuals.
In humans, chimerism can occur naturally after organ transplants, in which cells of the organ begin to grow in other parts of the body.
Professor Juan Carlos Izpisua Belmonte, who leads the research, said, “These chimeric approaches could really be very useful in advancing biomedical research not only in the earliest stages of life but also in the newest stage of life.”
In 2017, he and his team created the first human-pig hybridwhere they introduced human cells into pig tissue at an early stage but found that the environment offered poor molecular communication.
As a result, the researchers decided to study laboratory-grown chimeras using a more closely related species.
The great ape chimeric embryos were monitored in the laboratory for 19 days before they were destroyed.
According to the scientists, the results, published in the journal Cell, showed that human stem cells “survived and were integrated with better relative efficiency than previous experiments on pig tissue”.
The team said that a better understanding of how cells of different species communicate with one another could provide “unprecedented insight into the earliest stages of human development” and provide scientists with a “powerful tool” for studying regenerative medicine.
Prof. Izpisua Belmonte insisted that her research conform to current ethical and legal guidelines, saying: “As important as these results are to health and research, as we have done this work, with the utmost consideration of ethical considerations and in close coordination with The regulatory agencies is equally important.
“Ultimately, we are doing these studies to understand and improve human health.”
Dr. Anna Smajdor, professor and biomedical ethics researcher at the University of East Anglia’s Norwich Medical School, responded to the research: “This breakthrough reinforces an increasingly inescapable fact: biological categories are not fixed – they are fluid.
“This presents us with considerable ethical and legal challenges.”
She added, “The scientists behind this research claim that these chimeric embryos offer new opportunities because ‘we cannot do certain types of experiments on humans.’
“But whether these embryos are human or not is questionable.”
Prof. Julian Savulescu, Director of the Oxford Uehiro Center for Practical Ethics and Co-Director of the Wellcome Center for Ethics and Humanities at Oxford University, said: “This research opens Pandora’s box to human-non-human chimeras.
“These embryos were destroyed after 20 days of development, but it is only a matter of time before human-non-human chimeras develop successfully, possibly as a source of organs for humans. This is one of the long-term goals of this research.
“The key ethical question is, what is the moral status of these novel creatures? Before experimenting on live-born chimeras or having their organs removed, it is important that their mental abilities and their lives are properly assessed.”