FIGURE 2

Oxytocin Induces Proliferation and Activation of hiPSC-Derived Epicardial Cells. (A) Screening results for 15 candidate neuroendocrine peptides, shown as the percentage of hEpiCs expressing H3P after exposure to each compound; n = 3 per condition. (B) Experimental timeline used to quantify OXT-induced epicardial activation. (C,D) Confocal immunofluorescent images (C) and quantification (D) of proliferating hEpiCs after 3 days OXT exposure. In (C), epicardial cells are labeled with WT1 (red), epithelial membranes are labeled with TJP1 (magenta), proliferating cells (arrowheads) are labeled with Ki67 (green), nuclei are labeled with DAPI (blue); n = 6 images per condition, scale bar: 25 µm. (E,F) Absolute counts of DAPI-labeled epicardial cell nuclei after 3 days exposure to OXT (E) or thymosin β4 (F), a compound previously shown to induce epicardial activation; n ≥ 6 per condition. (G) qRT-PCR data for epicardial cells exposed to OXT, showing an increase in EpiPC (WT1, TCF21), EMT (SNAI1), and mesenchymal (NT5E) markers; n = 4 per condition.