It is odd that humans and mice have a lot in common. Their bodies seem to operate in such a way that, unfortunately for them, mice are often used as guinea pigs by scientists in order to discover medicines for the protection of humans. It is now possible that human embryos could one day be created in the lab using stem cells alone, following a major breakthrough. For the first time, pioneering scientists have created artificial mouse embryos without the need for sperm or egg cells.
The Cambridge University team used stem cells which were essentially ‘blanks’ which could transform into any type of cell in the body. Until now, scientists have not been able to make them grow into a complex structure, such as an embryo or a human organ. But by combining different kinds of cells, the researchers succeeded in making them ‘talk’ to each other, using chemical signals so they can develop into an embryo almost identical to one of a normal mouse. The team used two types of stem cells – embryonic, and trophoblast, which went on to create the placenta. They added a gel to act as a scaffold, holding the developing embryo in place.
Professor Magdalena Zernicka-Goedz, who co-led the research, said the scaffold was key to the breakthrough. She added: ‘We knew interactions between different types of stem cells are important for development, but the striking thing our work illustrates is that this is a real partnership. These cells truly guide each other. Without this partnership, the development of shape and form and the activity of key biological mechanisms doesn’t take place properly.’
The artificial embryo followed the same development pattern as a natural one created, using sperm and egg cells. It was 92% similar to a normal embryo. But the lab-grown embryo is unlikely to develop normaly if implanted in a womb because another type of stem cell would be needed to give it nourishment.
Professor Zemicka-Goedz said:
‘The breakthrough could help researchers learn why 2 in 3 human pregnancies fail in the early stages. Most human embryos used in stem cell research are donated after being left over from fertility treatments. The law only allows them to be used for research for 14 days after fertilization… We think it would possible to mimic a lot of the developmental events occurring before 14 days, using human embryonic and extra embryonic stem cells, using a similar approach to our technique using mouse stem cells. We are optimistic this will allow us to study key events of this critical stage of human development without having to work on embryos. Knowing how development normally occurs will allow us to understand why it goes wrong.’
Dr Andrew Chisholm of the Welcome Trust, which part funded the research, said: ‘In theory similar approaches could be used to explore human development shedding light on the role of the maternal environment in birth defects and health.’ Dr Dusko Ilic, a stem cell expert from Kings College London, described the research as ‘a masterpiece’.
On reflection, if the money that our government spends to bolster corrupt regimes abroad is used for research of this kind, most humans worldwide will ultimately profit in combatting birth defects, making them a thing of the past.