British Scientists Successfully Create the World’s First Artificial Embryo in the Laboratory Using Stem Cells
Scientists at the University of Cambridge, UK, have successfully created the world’s first artificial embryo of a mouse by utilizing two types of stem cells and a 3D framework for the embryo to develop, according to Nature World News. The research findings were published in the journal Science on March 2.
These embryo-like structures are at the earliest development stage of humans. They lack heart and brain structures. However, scientists state that one day they could enhance understanding of genetic diseases or the causes of miscarriage.
Nonetheless, this research raises significant legal and ethical questions, as there are currently no laws regulating the creation or handling of artificial embryos in many countries, including the United States. The rapid progress in this field and the increasing complexity of these structures have led bioethics experts to warn as they approach the boundaries of life.
“Unlike human embryos arising from in vitro fertilization (IVF), where a legal framework is established, there currently are no clear regulations governing human embryo models derived from stem cells. Regulations are needed to provide a framework for creating and using human embryo models derived from stem cells,” said James Briscoe, Deputy Director of Research at the Francis Crick Institute.
The research team utilized genetically modified mouse embryonic stem cells (ESCs), which function in forming the body, and trophoblast stem cells (TSCs), which form the placenta, to successfully develop a self-assembling structure capable of communicating, resembling a natural embryo.
Artificial embryos created using two types of stem cells. (Photo: University of Cambridge).
“It has regions that resemble an embryo anatomically, developing in the right place and at the right time,” stated Magdalena Zernicka-Goetz, the lead author of the study.
This artificial embryo develops according to the model of a natural embryo, with ESCs on one side and TSCs on the other before they combine. Zernicka-Goetz emphasized the importance of communication between the two types of embryonic cells, stating they are capable of “talking to each other.”
“What stands out in our research is making the stem cells truly cooperate and influence each other to form the embryo,” Zernicka-Goetz added.
Zernicka-Goetz noted that this cooperation is crucial, as without it, the cells would not develop into the correct shape, and biological mechanisms could not occur at the right time. A third type of stem cell, responsible for forming the yolk sac, will be added in the future to create fully functional artificial embryos.
“The development of artificial embryos helps us study significant events in the early stages of human development without actually working on real human embryos,” Zernicka-Goetz explained.
Zernicka-Goetz told CNN that these embryo-like structures are also the first to contain germ cells that will continue to develop into eggs and sperm.
“I just want to emphasize that they are not human embryos. They are embryonic models, but they are very interesting because they closely resemble human embryos and are a very important pathway to explore why so many pregnancies fail,” Zernicka-Goetz remarked.
Zernicka-Goetz also mentioned that this is the first time a human embryo model has been created with three layers of tissue. However, while it shares some characteristics of natural embryos, it does not possess all of those traits.
Currently, synthetic human embryo models are limited to laboratory conditions.
Researchers hope these embryo models will shed light on human development during the 14 days following fertilization. This is a unified limit for scientists to develop and study embryos in the laboratory.
At present, synthetic human embryo models are restricted to laboratory conditions, and implanting a cell into the uterus would be illegal. Research on animals using stem cells from mice and monkeys has shown that even if scientists attempt to implant them, they cannot survive. This may be due to researchers not yet finding a way to fully replicate the conditions of a pregnancy.
Zernicka-Goetz stated that the goal of the research is not to create life but to prevent mishaps and understand why embryos sometimes do not develop after fertilization and implantation.
Roger Sturmey, a senior researcher in maternal and fetal health at the University of Manchester (UK), remarked: “We know very little about this step in human development, but it is a time when many miscarriages occur, especially in IVF environments. Currently, we can say that these ‘synthetic embryos’ share some characteristics with blastocysts, but it is important to recognize that the way synthetic embryos are formed differs from what happens when a normal embryo forms a blastocyst. There is much work to be done to identify the similarities and differences between artificial embryos and those formed from the combination of egg and sperm.”
