Figure 3.

Ectopic expression of Serpine1 impairs ESC undifferentiated state. (a) ESCs were transfected with empty vector (mock) or FLAG-tagged Runx1 and Serpine1 expression vector. Western blot stained with anti-FLAG antibody show the expression level of FLAG-Serpine1 and FLAG-Runx1 24 hr after transfection. (b) ESCs transfected with empty vector, FLAG-Serpine1 or FLAG-Runx1 were grown at clonal density (50-100 cells/cm²) for 7 days and then stained for alkaline phosphatase activity (scale bars, 1 cm). The percentage of undifferentiated (blue) and differentiated (red) colonies is reported. Bars represent SD of triplicates. *P < 0.05. (c) Expression level of stemness markers was measured 48 hr after transfection by qPCR. The data are expressed as fold changes relative to mock-transfected cells. Error bars represent SD of triplicates. *P < 0.01. (d) Expression levels of early differentiation markers of ectoderm (Fgf5), endoderm (Sox17) and mesoderm (T, also known as brachyury) were measured 48 hr after transfection by qPCR. Error bars represent SD of triplicates. *P < 0.01.