MOUSE EMBRYO CREATED FROM STEM CELLS FOR THE FIRST TIME
By using two different types of stem cell, researchers at the University of Cambridge have successfully built an artificial mouse embryo in the laboratory – a breakthrough that may help us understand why two out of three human pregnancies fail during the early stages.
Our knowledge of early embryo development is still quite hazy, partly because of the strict rules around research involving real-life human embryos. The technique pioneered in Cambridge involves bringing together two types of stem cell: the embryonic stem cells (ESCs) that will go on to form the mouse’s body, and the trophoblast stem cells (TSCs) that will go on to form the placenta.
The scientists placed both types of cell onto a ‘scaffold’ called an extracellular matrix, and observed how they then organised themselves just as they would in a real-life embryo, with ESCs at one end and TSCs at the other. Because the third type of stem cell involved in the natural process – the endoderm stem cells that form the ‘yolk sac’ – was not present, the resulting embryos are not able to develop into actual mice.
Previous attempts to create embryos in the lab using only ESCs all failed, but it’s hoped this breakthrough will lead to the creation of new avenues for embryo research.
“We are very optimistic that this will allow us to study key events of this critical stage of human development without actually having to work on embryos,” said researcher Prof Magdalena Zernicka-Goetz. “Knowing how development normally occurs will allow us to understand why it so often goes wrong.”