Activin A Modulates CRIPTO-1/HNF4α⁺ Cells to Guide Cardiac Differentiation from Human Embryonic Stem Cells

Figure 5

Human ESC-CM differentiation potential after CRIPTO-1 interference. CRIPTO-1 blocking peptide (BP) impaired ActA-directed in vitro cardiac differentiation. (a) Gene expression of the TGF-β family members NODAL and CRIPTO-1 during a 13-day differentiation period. Dashed lines show basal expression levels of undifferentiated ESCs. (b) Normalized fold change of the mesodermal marker BRACH, measured at day 2 of differentiation after CRIPTO-1 BP treatment. Data, normalized for the housekeeping genes GAPDH, HPRT, and RPL13a, are representative of three independent experiments and expressed as mean SEM. (c) Brightfield pictures of ESC-CMs at day 13 of differentiation after CRIPTO-1 BP treatment or after addition of a human CRIPTO-1 antibody (Ab). (d) Percentage of contracting EBs and of (e) beating area surface in differentiated CMs pretreated with 100 ng/mL ActA and 5 µM CRIPTO-1 BP or pretreated with 100 ng/mL ActA and a human CRIPTO-1 Ab (10 µM). Data, normalized for the housekeeping genes GAPDH, HPRT, and RPL13a, are representative of four independent experiments and expressed as mean SEM. Significant differences are indicated as : versus control; : versus control and §§ versus 10 ng/mL ActA; : ∗∗∗ versus control. Scale bar = 200 μm.

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