In vitro investigation of mammalian peri-implantation embryogenesis†

The embryos attach and invade the uterus, establishing the connection with their mother in peri-implantation development. During this period, the pluripotent epiblast cells of the embryo undergo symmetry breaking, cell lineage allocation, and morphogenetic remodeling, accompanied by the dramatic changes of transcriptomic, epigenomic, and signaling pathways, and preparing the stage for their differentiation and gastrulation. The progress in mouse genetics and stem cell biology has advanced the knowledge of these transformations, which are still largely hindered by the hard accessibility of natural embryos. To gain insight into mammalian peri-implantation development, much effort has been made in the field. Recently, advances in the prolonged in vitro culture of blastocysts, the derivation of multiple pluripotent stem cells, and the construction of stem cell-based embryo-like models have opened novel avenues to investigate peri-implantation development in mammals, especially humans. Combining with other emerging new technologies, these new models will substantially promote the comprehension of mammalian peri-implantation development, thus accelerating the progress of reproductive and regenerative medicine.