Fig. 2: Detection of secreted proteins in sorted mouse trophoblast endocrine cells.

a Workflow for the cell sorting and protein expression analysis of mouse trophoblast endocrine cells from mice at day 16 of pregnancy. b Fluorescent image of placenta showing EGFP in Tpbpa positive cells (junctional zone of the placenta; green) and tdTom (red) for Tpbpa negative cells. The fetus for the placenta is also shown, and as expected is only tdTom positive. Scale bar is 250 mm. c Representative image of cell sorting of EGFP/tdTom cells by fluorescence-activated cell sorting. d Expression of junctional zone and labyrinth zone markers, Tpbpa (dark pink bar) and Mct4 (light blue bar), respectively in the EGFP and TdTom sorted cells. e Expression of markers for junctional zone cell types, spongiotrophoblast cell (Prl8a8; purple bar), glycogen cells (Gjb3; green bar), and giant cells (Hand1: light blue bar). f Pipeline and results of the analysis of proteins detected by mass spectrometry in sorted Tpbpa+/EGFP cells. g Pathway over-representation analysis using Reactome pathway by STRING V.11 for the 105 secreted placental proteins expressed by both mouse and human placenta. Data presented as mean ± SEM and genes expressed relative to geometric mean of two housekeeping genes: RPII and Hprt. Asterisks denote statistical significance to the Tpbpa+/EGFP sorted cells, using t-test, *p < 0.05, **p < 0.01, n = 5 for each group.