This research details the creation of CREST, a sophisticated three-dimensional in vitro platform designed to model the complex process of human embryo implantation. By combining primary endometrial stromal and epithelial cells within a specialized hydrogel scaffold, the authors successfully replicated the hormonal transitions of the menstrual cycle, including the critical window of uterine receptivity. The study demonstrates that this model supports the attachment and invasion of human embryos and stem-cell-derived blastoids, achieving higher rates of organized development than previous methods. Using single-cell RNA sequencing, the researchers mapped the intricate molecular crosstalk between the invading trophoblast and the surrounding maternal tissue. Their findings identify specific ligand-receptor interactions, such as the AXL signaling pathway, which are essential for supporting early pregnancy and placental formation. This platform offers a personalized tool for investigating the origins of infertility and testing treatments to improve reproductive success.

References:

• Modeling human embryo implantation in vitroMolè, Matteo A. et al.Cell, Volume 189, Issue 1, 87 - 105.e28