Fig. 6.

E2 stimulates DNA replication in human fetal SSCs. Analysis of DNA replication in the absence or presence of 100-ng/ml E2 was measured by BrdU incorporation in human fetal SSCs co-cultured with Sertoli cells. Representative image of BrdU fluorescence (green) (white arrow) and DAPI (blue) in control (a) and E2-treated (b) groups. Scale bar: 50 μm. c Percentage of BrdU-positive cells relative to the total cell count (200 random cells) after 1, 3, or 5 days of vehicle control or E2 treatment. Data are shown as mean ± SEM (n = 3 in each group). *P < 0.01 vs. control