Epidermal growth factor promotes trophoblasts transcriptome resembling human embryo during reconstructing blastoids from extended pluripotent stem cells.

Human blastoids have been derived from multiple pluripotent stem cells. However, trophectoderm(TE) lineage in them is not assemble with corresponding human blastocysts. Here, transcriptional profiling showed that TE-like cells derived from human extended pluripotent stem cells(EPSCs) recapitulate human pre-implantation TE through precisely upregulating the expression of multiple TE-specific maker genes and maintaining gene imprinting. Adding epidermal growth factor(EGF) promoted TE lineage related signaling pathways and increased the efficiency of generating blastoids. Single-cell transcriptomics showed upgrading lineage segregation of the optimized blastoids with high fidelity to human blastocysts, especially the primitive endoderm. Together, our findings establish a scalable and tractable system for TE formation, indicate roles for TE lineage specific regulatory program and facilitate the blastoid re-construction.