DMSO derives Trophectoderm and Clonal Blastoid from Single Human Pluripotent Stem Cell

Human naive pluripotent stem cells (nPSCs) can differentiate into extra-embryonic trophectoderm (TE), a critical step in the generation of the integrated embryo model termed blastoid. The current paradigm of blastoid generation necessitates the aggregation of dozens of nPSCs treated with multiple small molecule inhibitors, growth factors, or genetic modifications to initiate TE differentiation. The presence of complex crosstalk among pathways and cellular heterogeneity in these models complicates mechanistic study and genetic screens. Here, we show that a single small molecule, dimethyl sulfoxide (DMSO), potently induces TE differentiation in basal medium without pharmacological and genetic perturbations. DMSO enhances blastoid generation and, more importantly, is sufficient for blastoid generation by itself. DMSO blastoids resemble blastocysts in morphology and lineage composition. DMSO induces blastoid formation through PKC signaling and cell cycle regulation. Lastly, DMSO enables single nPSC-derived clonal blastoids, which could facilitate genetic screens for mechanistic understanding of human embryogenesis.