Amniotic sac in a dish: Stem cells form structures that may aid of infertility research
Despite the importance of this critical stage, scientists haven't had a good way to explore what can go wrong, or even what must go right, after the newly formed ball of cells implants in the wall of the human uterus. But a new achievement using human stem cells may help change that. Tiny lab-grown structures could give researchers a chance to see what they couldn't before, while avoiding ethical issues associated with studying actual embryos. A team from the University of Michigan reports in Nature Communications that they have coaxed pluripotent human stem cells to grow on a specially engineered surface into structures that resemble an early aspect of human development called the amniotic sac. The cells spontaneously developed some of the same structural and molecular features seen in a natural amniotic sac, which is an asymmetric, hollow ball-like structure containing cells that will give rise to a part of the placenta as well as the embryo itself. But the structu...