“Using Only Skin Cells, Israeli Lab Makes Synthetic Mouse Embryos With Beating Hearts: In Peer-Reviewed Breakthrough, Embryos Are Grown from Stem Cells; Scientists Say Method May One Day Be Used to Ethically Grow Cells for Replacement Human Organs”, 2022-08-01 (; backlinks):
Researcher tells ToI: There was no sperm, no egg, no uterus.
An Israeli lab has grown synthetic mouse embryos with brains and beating hearts—in an egg-free sperm-free procedure that used stem cells taken from skin.
The breakthrough, published on Monday in the peer-reviewed journal Cell, represents the first time that an advanced embryo of any species has been created from stem cells alone, cell biologist Prof. Jacob Hanna of the Weizmann Institute of Science told The Times of Israel.
Hanna, who led the research, said that previous attempts had led only to blastocysts, meaning the structures formed in the early development of mammals. Blastocysts have a tiny fraction of the million-plus cells that are in his embryos.
“It’s remarkable”, he commented. “There was no sperm, no egg and no uterus, but we managed to get embryos formed from stem cells alone to 8 days—a third of the gestation period of a mouse—with a beating heart.”…Hanna said synthetic embryo-like structures could be viewed very differently. They are similar to regular embryos, but are not viable for implantation. He foresees a day when sick patients may give skin or blood cells for the growth of artificial embryo-like structures, which could in turn yield the cells needed to grow organs.
The key to Hanna’s achievement is a special incubator system in which each embryo is in a bottle with liquid, and the bottle is spinning to ensure it does not attach to the side. The incubator creates all the necessary conditions for the embryo’s development, including gas concentration, pressure and temperature. The liquid—developed in his lab—gives the embryos all the nutrients, hormones, and sugars they need.