Extended Data Fig. 2: Regulation of trophoblast cells.

a, The number of Cdx2 transcript reads per million mapped reads (r.p.m.) as measured in bulk samples of: ES cultured in 2i medium and TS cells cultured in TX medium, TS cells cultured in blastoid medium, and blastoids and blastocysts. Note that the blastoids and blastocysts comprise both trophectoderm and ICM cells, the latter expressing only very low levels of Cdx2. n = 2 independent biological samples (see Methods). b, Measurement of CDX2 fluorescent intensity in blastoids and blastocysts. Blastoids were fixed and stained with an anti-CDX2 antibody (see Methods). E3.5 blastocysts were used as a positive control. n = 15 independent blastoids or blastocysts. Error bars are s.d. c, The number of Stat3 transcripts per million reads as measured in bulk samples of ES and TS cells and blastocysts. d, Immunostaining for phosphorylated STAT3 in a representative blastocyst colony of ES and TS cells (see Methods). Scale bar, 50 µm. e, TS cells cultured in the presence of different concentrations of the STAT/GP130 pathway inhibitor SC144. Both growth and viability were affected by concentrations of at least 1 µM. f, The number of transcripts per million reads for the STAT pathway ligands Il11, Lif and Il6, along with their receptors, as measured in bulk samples of ES cells, TS cells and blastocysts. g, Whole-mount single-molecule FISH for Il11, in an E3.25 blastocyst. Scale bar, 50 µm. See Methods for further details.