Using Reprogrammed Stem Cells to Mimic Early Human Embryo Development

Monday - September 18 2023, 21:14 UTC - 1 year ago

Reprogrammed stem cells, chemicals, and precise ratios were mixed and then observed for self-assembly. Results showed a structure resembling an embryo 1% of the time, being dependent on placenta cells. This can improve IVF success rates and test medicines during pregnancy, though improvements in the failure rate of the model must be made first.

Instead of a sperm and egg, the starting material was naive stem cells which were reprogrammed to gain the potential to become any type of tissue in the body. Chemicals were then used to coax these stem cells into becoming four types of cell found in the earliest stages of the human embryo: * epiblast cells, which become the embryo proper (or foetus) * trophoblast cells, which become the placenta * hypoblast cells, which become the supportive yolk sac * extraembryonic mesoderm cells A total of 120 of these cells were mixed in a precise ratio – and then, the scientists step back and watch .

About 1% of the mixture spontaneously assembling themselves into a structure that resembles, but is not identical to, a human embryo. They generate the cell types and then have the right environment to grow the embryo like structure. This study shows other parts of the embryo will not form unless the early placenta cells can surround it. There is talk about improving in vitro fertilization (IVF) success rates by helping to understand why some embryos fail or using the models to test whether medicines are safe during pregnancy .

The current 99% failure rate would need to be improved, otherwise researchers would not be able to differentiate the copycat embryo and the mimicking process problems from real problems.