Immunofluorescence analysis. Immunofluorescence analysis of actin cytoskeleton and focal contacts of TCPS or hydrogel MDCK growing cells. A) Actin stress fibers (left panel), vinculin stains (middle panel) and their merge (right panel) of MDCK cells 2 days after seeding. Small white arrows indicate short focal contacts and big white arrows indicate the long ones. In the ISA23-75 panels, red small arrows indicate filopodia red big arrows indicate lamellipodia. Nuclei are labeled with DAPI and visualized in blue. Scale bar: 10 μ m. B) The percentage of cell islands with well formed stress fibers is plotted against the time after seeding. 62 (TCPS), 105 (AGMA1-75) and 72 (ISA23-75) cell islands from 3 different experiments were scored.