Figure 1.

ECM facilitates growth-factor-induced proliferation. GECs were plated into culture wells that were coated with collagen or were uncoated (plastic) in serum-poor medium that contained EGF (100 ng/ml), HGF (50 ng/ml), bFGF (50 ng/ml), thrombin (5 U/ml), or medium alone (Med). Cell number was determined 3 days after plating. All growth factors stimulated proliferation only when GECs were adherent to collagen. Significant differences were present among groups (upper panel: P < 0.0001 ANOVA; *P < 0.0001, ⁺P < 0.01 collagen versus plastic; lower panel: P < 0.0001 ANOVA; *P < 0.0001, ⁺P < 0.05 collagen versus plastic). Each bar represents mean ± SEM of 8 to 12 wells.