The ability to induce mouse stem cells to self-assemble into structures resembling early embryos with a digestive tract, a developing brain, and a beating heart was found by scientists at the Weizmann Institute in Israel.
Some cells underwent chemical pretreatment to activate genetic programmes that would drive them to develop into the yolk sac or placenta, while other cells naturally underwent organ and other tissue development. The researchers stated that 0.5% of stem cells merged to form tiny balls that gave rise to distinct tissues and organs, whereas the bulk of stem cells failed to grow into structures resembling embryos.
Researchers believe that the discovery could eventually lead to new sources of cells and tissues to be used in human transplants, reduce the use of animals in research, and reduce the need for animal testing altogether. Skin cells from a leukaemia patient could potentially be transformed into bone marrow stem cells to treat their condition.
Other cells normally underwent organ and other tissue development, while some cells received chemical treatment to trigger genetic programming which would lead them to develop into the placenta or yolk sac. The synthetic mouse embryos were 95% equivalent to real mouse embryos in terms of internal structure and cell genetic profiles.
The usefulness of the emerging organs was apparent to the scientists.
In the near future, it is predicted that the live constructs will increase our knowledge of how tissues and organs evolve during the development of natural embryos.
Parvathy Sukumaran 
