Fig. 5

Schematic of our hypothesis on the mechanism by which collective cell migration induced by the removal of ring-barrier induces the spatial self-organization into gastrulation-like phenotype. A Comparison of spatial self-organization within the hiPSC colony with or without the ring-barrier in the absence of exogenous differentiation factors. In the first step, hiPSCs self-assemble into a colony primarily through cell–substrate and cell–cell adhesion. In the second step, by removing the ring-barrier, the hiPSC colony spontaneously differentiated into SOX17⁺/BRACHYURY⁺ gastrulation-like structures through collective cell migration without exogenous supplements. The hiPSC colonies were compared after further exposure to HA in culture conditions without the ring-barrier. B A detailed description of the spatial self-organization process within the hiPSC colony through collective cell migration in the absence of exogenous differentiation factor