does not require sperm and eggs. Scientists have relied on artificial means to "synthesize" new life in the laboratory. The results of the
experiment were published in the top academic journal Nature on August 25. The paper shows that the brain, beating heart and other body organs can be observed in the synthetic mouse embryo, which can survive for a total of eight days.
The research team is composed of scientists from University of Cambridge , California Institute of Technology and University of Washington. They said that this experiment has discovered a new way to reproduce the first characteristics of life. In studying the early stages of organ development, artificial organs It is of great significance in areas such as synthesis. The "artificial means" used by the
team is stem cells , which are the only "universal cells" in the human body that have the function of regenerating various tissues and organs. Specifically, they use three types of stem cells discovered during the early development of mammals. : Embryonic stem cells (ESC), trophoblast Stem cells (TSCs), induced extraembryonic endoderm stem cells (iXEN), of which embryonic stem cells will develop into body tissue, trophoblast stem cells will become placenta , induced extraembryonic endoderm stem cells will also support embryonic development.
To synthesize embryos, researchers put the above three types of stem cells together in appropriate proportions and let them "talk" to each other in a laboratory environment to simulate the interactions between cells during natural conception.
went through several consecutive days of development until day 8.5. The embryonic model clearly showed head folds in the forebrain and midbrain regions, a heart-like structure, a trunk composed of neural tubes and somatic cells, and a neuronal epithelium. The germ layer progenitors of the tail bud (tail bud), a gut tube, and primordial germ cells.
Illustration: The red box shows the development process of the synthetic embryo, and the lower part is the natural embryo
. After that, the embryo showed no signs of further development, and the heart area expanded abnormally on the 9th day. Magdalena Zernicka-Goetz, a scientist from the University of Cambridge in the
team, said that the ability to form a brain, especially the forebrain area, is the most important progress of this experiment, because this is the first time to clearly develop the forebrain (or the entire brain) The embryonic model also opens up new possibilities for studying neural development mechanisms.
Illustration: A is the forebrain, H is the heart, S is the body segment
In addition to the final experimental results (i.e., the generated embryos), Zernicka-Goetz also added that this experiment also helped them clarify how the embryos build themselves. Mechanisms, such as how extraembryonic tissue guides embryonic stem cells to signal the correct structure to form; how cells move between compartments when multi-layered body structures emerge: and how this correctly sets the scene for neurogenesis, and more.
Researchers are now developing similar human models to generate specific organ types and understand the mechanisms behind key processes. However, under current British law, human embryos in the laboratory are only allowed to develop until day 14.
Compiled by: Nandu trainee reporter Yang Bowen
