Capturing Human Trophoblast Development with Naïve Pluripotent Stem Cells In Vitro

Abstract Trophoblast are extra-embryonic cells that are essential to maintain pregnancy. Human trophoblasts arise from the morula as trophectoderm (TE), which, after implantation, differentiates into cytotrophoblast (CT), syncytiotrophoblast (ST), and extravillous trophoblast (EVT) composing the placenta. Here we show that naïve, but not primed, human pluripotent stem cells (PSCs) recapitulate trophoblast development. Naïve PSC-derived TE and CT (nCT) recreated the human and monkey TE-to-CT transition. nCT self-renewed as CT stem cells and had the characteristics of proliferating villous CT and CT in the cell column of the first trimester. Notably, although primed PSCs differentiated into trophoblast-like cells (pBAP), pBAP were distinct from nCT and human placenta-derived CT stem cells, exhibiting properties consistent of the amnion. Our findings establish an authentic paradigm for human trophoblast development, demonstrating the invaluable properties of naïve human PSCs. Our system will provide a platform to study the molecular mechanisms underlying trophoblast development and related diseases.