Fig. 2. Native LN5-rich ECM reinforces cell-cell interactions between Caco-2 cells. Caco-2 cells were plated at 20,000 cells/cm² on plastic () or on native LN5-rich ECM () deposited by HT29-MTX cells. (A) Phase contrast micrography (X 25; bar, 200 µm) shows that domes appear on cultures grown on ECM 2 days earlier than on plastic support. (B) shows the confluence rates observed by phase microscopy. (C) At the indicated times, domes were counted. Values represent mean±s.m.d. from triplicate wells from three independent cultures. (D) shows a 3D confocal reconstruction of the diffusion of FITC-conjugated biotin added at the apical side of Caco-2 cultures grown on plastic (a) or on LN5-rich ECM (b). (bar, 10 µm). Note that the presence of ECM restricts biotin diffusion at the apical compartment, which indicates a reinforcement of cell-cell interactions as compared to cultures grown on plastic without ECM. The result is representative of three independent experiments.