Fig. 2
Acute hypoxic treatment enhanced DE formation. a FACS analysis of anti-CXCR4 staining of H1 cells differentiated for three days towards (blue population) under various hypoxia conditions. Undifferentiated H1 cells were gated as negative controls (gray populations). The x-axis indicates the APC channel. b Summary of the percentages of CXCR4+ cells (with various oxygen concentrations) from H1 or H9 differentiation for three days toward DE cells. c QPCR analysis of experiments performed in (b). All expression levels were first normalized to endogenous GAPDH. For pluripotency markers (upper panels), samples were normalized to undifferentiated H1 or H9 samples, which were arbitrarily set to 1. For other markers (mid and lower panels), samples were normalized to the 20 % O2 samples, which were arbitrarily set to 1. d Left panel, schematics of various lengths of hypoxic treatment. Right panel, qPCR analysis at day four of differentiation for H1 or H9 cells. The x-axis indicates the number of days treated with 1.5 % O2 as indicated in the left panel. Samples were normalized to those from normoxia, which were arbitrarily set to 1. e Confocal images of OCT4, FOXA2, and SOX17 immunofluorescence staining at day two of differentiation under 20 % or 1.5 % O2. Scale bars = 50 μm. All data are mean ± S.D. ***p <0.001; **p <0.01; *p <0.05, by one-tailed t-test. n.s. no significant difference