Extended Data Fig. 4: Evolution of the number of cells in the blastoid compartments.

a, E3.5 and E4.5 blastocysts (n = 6) were immunostained using Nanog and PDGFRα antibodies, and nuclei were counterstained with DAPI (see Methods). b, Percentage of blastoids including GATA6⁺ cells from a total number of 14 blastoids. c, Number of cells in each of the blastoid or blastocyst compartments, namely trophoblast, embryonic and primitive endoderm, were counted based on an immunostaining for Nanog, GATA6 and PDGFRα. The number of trophoblast was counted based on the expression of constitutive GFP. The quantification was done at 48, 72 and 86 h. Note that, for most experiments presented herein, blastoids are harvested at 65 h (see Methods). The horizontal bars represent the mean number of cells. The coefficient of variation (relative s.d.) is 19.4% for E3.5 blastocysts and 23.6% for blastoids at 48 h. n = 6 independent E3.5 blastocysts and E4.5 blastocysts.