Fig. 4. Inhibitory effect of Smad7 in serum-free conditions. (A) Colony morphologies of fSmad7-10⁺ and fSmad7-10^- ES cells in serum-free medium. fSmad7-10⁺ (middle), fSmad7-10^- (right), and EB3 (as control, left) ES cells were seeded at 2000 cells/well in six-well plates, and cultured in FCS-containing medium for 1 week. Numbers indicate numbers of colonies appearing (n=3). Bars, 5 mm. (B) Relative numbers of each transfectant present on Day 7 of culture compared with Day 0. Each bar represents the mean ± s.e.m. (n=4). (C) Relative proliferation intensity is shown as total cell number/number of colonies appearing, compared with that of EB3 ES cells (100%). Each bar represents the mean ± s.e.m. (n=3).