According to the scientists of the Weizmann Institute in Israel, stem cells from mice can be transformed into primitive embryo-like formations with their own intestinal tract, brain and functional heart.
They called them “synthetic embryos” because they were created without fertilized eggs. They should, in the short term, help us better understand how organs and tissues form during the development of natural embryos. And not only that.
The study's authors are optimistic that the procedure could reduce the need for animal testing and ultimately lead to new sources of cells and tissues for human transplants. Skin cells of a leukemia patient, for example, could be converted into bone marrow stem cells to alleviate his condition.
Synthetic embryos, natural benefits
“Surprisingly, we show that the embryonic stem cells generate whole synthetic embryos. They include the placenta and yolk sac that surround the embryo,” said the professor. Jacob Hannah, head of the research team. “We are really excited about this work and its implications.” The research was published in the scientific journal Cell (I link it to you here).
Last year, the same team built a kind of mechanical womb that allowed natural mouse embryos to grow grow outside the uterus for several days.
The phases of the research
In this latest study, the same “mechanical womb” was used for nourish the cells mouse stem cells for more than a week, nearly half the gestation time of a mouse. Some of the cells were pre-treated with chemicals, which triggered genetic programs to develop in the placenta or sac calf, while others developed without intervention on organs and other tissues.
Results? Most stem cells have failed to form embryo-like structures, but approx 0,5% it combined and grew distinct tissues and organs. Synthetic embryos are 95% identical in structure and genetic profile to natural mouse embryos, and have functional organs.
Synthetic embryos: possible developments
Prof. Hanna is keen to specify than synthetic embryos they are not “real” embryos and do not have the potential to develop into living animals, or at least they did not when transplanted into the uterus of female mice. Based on this research he founded a company called Renewal Bio, which aims to cultivate synthetic human embryos to provide tissues and cells for medical conditions. It can be done?
“In Israel and many other countries, such as the USA and UK, it is legal. We have approval ethics to do so with human induced pluripotent stem cells. This will provide an ethical and technical alternative to the use of embryos,” Hanna said.
Ethical doubts are inevitable
Doctor James Briscoe of the Francis Crick Institute in London (which was not involved in the research) find it to be It is important to discuss how best to regulate this type of research before synthetic human embryos are developed. I agree with him.
Human synthetic embryos are not an immediate perspective. Further developments will be needed, it is not as simple as for mouse ones. For this reason, now is the right time to define a legal and ethical framework: this type of research must be regulated, and the current regulations must be updated.
“There will always be a gray area,” predicts the scientist. “However, as scientists and as a society, we must unite to determine where the line is and what is ethically acceptable.”
And it is no small thing.
