01716nas a2200229 4500000000100000000000100001008004100002260001200043653002700055653001800082653001500100653002700115100001500142700001200157700001600169245003300185856005500218300001000273490000600283520118300289022001401472 2025 d c2025-0110aBiomedical Engineering10aEmbryogenesis10aEmbryology10aPluripotent Stem Cells1 aXufeng Xue1 aYue Liu1 aJianping Fu00aBioengineering embryo models uhttps://www.nature.com/articles/s44222-024-00241-x a11-290 v33 aStem cell-based embryo models, which recapitulate symmetry breaking, pattern formation and tissue morphogenesis during early development, provide promising experimental tools to study the development of mammalian species, including humans. Despite considerable progress in embryo modelling using cultured stem cells, generating embryo models with high fidelity, efficiency, controllability, and in vivo-like cellular organization and tissue architecture remains challenging. This is largely due to intrinsic variabilities in self-organization and differentiation of mammalian stem cells in uncontrolled culture environments. In this Review, we argue that bioengineering tools, which are powerful for controlling topological boundaries and dynamic chemical and mechanical signals, can efficiently guide symmetry breaking, pattern formation, tissue morphogenesis and tissue–tissue interactions. We discuss pattern formation and morphogenesis during embryonic development and examine different embryo models to highlight the importance of bioengineering strategies in developing models with improved efficiency, reproducibility, controllability, complexity and in vivo relevance. a2731-6092