In what is likely a first for science, a team at the University of Cambridge used mice stem cells to create a very close to natural embryo.
The scientists used two types of stem cells and a 3D scaffold to successfully make something that closely resembles a mouse embryo, the BBC reports. Prior attempts at the same had limited success because embryo development requires different cells to work together.
The researchers say this development will work to improve fertility treatments, and could also be used to find out more about how early embryos develop.
However, experimentation on human embryos is strictly regulated in most countries, and banned after 14 days.
Once an egg has been fertilized, it divides to make embryonic stem cells, which are called the body’s “master cells.” These embryonic stem cells group together inside the embryo on one end, forming a blastocyst. This is the building block of what will later become a full embryo.
The researchers made their embryo using embryonic stem cells and a second type, known as extra-embryonic trophoblast stem cells, which form the placenta. Magdalena Zenricka Goetz, lead author on the study, says,
We knew that interactions between the different types of stem cell are important for development, but the striking thing that our new work illustrates is that this is a real partnership – these cells truly guide each other.
The team says the embryo they created is not likely to survive and develop into a healthy fetus, as that would require a third kind of stem cell that develops the yolk sac a fetus would need.
This same group of scientists had recently come up with a process that allows blastocysts to develop in a lab up to 14 days. They have also grown the artificial mice embryos to the equivalent stage, and are now applying the same technique to create artificial human embryos.
If successful, their work could prod officials to extend the legal limit of 14 days on experimenting with human embryos.
The study was published in the journal Science.