For the first time, scientists from the Weizmann Institute of Science in Israel have succeeded in creating mouse embryos without using eggs and sperm. The researchers reported this in a journal article. cell.
Embryonic stem cells served as the basis of embryos – they can differentiate into the three main germ layers, but not into extra-embryonic tissues. The scientists reprogrammed some of the cells so that they can form the placenta and yolk sac, which are responsible for blood formation at a certain stage of development.
Scientists managed to achieve the formation of clusters of 10 thousand cells, but only 50 of them continued to develop. For 8.5 days – half of a typical mouse pregnancy – the embryos were in an artificial womb. Embryos were placed in small containers containing a nutrient solution, and the containers were fixed on a rotating cylinder – this way the scientists simulated the flow of blood and nutrients to the placenta, and also reproduced the atmospheric pressure in the uterus.
On the sixth day, the foundations of the central nervous system emerged in the embryos and soon the brain was formed. On the eighth day, the heart, vessels, and intestines were formed. Both in structure and genetically, the embryos almost completely coincided with the natural ones.
“Our next task is to understand how stem cells know what to do: how they self-assemble into organs and navigate to their assigned locations within the embryo. And because an artificial uterus is transparent unlike a natural one, it is to model congenital and acquired defects in human embryos. can be helpful,” say the study’s authors.
Further, the bioreactor can be an incubator for cells, tissues and organs grown for transplantation.