Comparison of integrin-mediated functions in WT and kindlin-2^+/− ECs. The kindlin-2^+/− aortic ECs show suppressed adhesion (A) and migration (B) on fibrinogen and vitronectin compared with WT ECs while these responses are the same in both kindlin-2^+/− and WT EC on collagen I and fibronectin. Data are expressed as means ± SEM of quadruple samples and are representative of at least 3 independent experiments of pooled EC of 3-6 mice. (C) Reduced ERK1/2 and p90RSK phosphorylation in VEGF-stimulated kindlin-2^+/− cells adherent to fibrinogen compared with WT ECs while it was similar for both cell types on fibronectin and BSA. Western blots were reprobed with Ab to total ERK1/2 to demonstrate equal loading of proteins. The images are representative of 2 independent experiments. (D right panel) Representative images of WT and kindlin-2^+/− ECs spread on various integrin ligands for 1 hour at 37°C (right panel). The cells are stained with Alexa 568–phalloidin. Scale bar, 50 μm. (D) Quantitative analysis of the data (left panel); reduced spreading of kindlin-2^+/− ECs on fibrinogen and vitronectin (right panel). The areas of ∼ 200 cells per group from 2 independent experiments were measured. (E) Impaired tube formation by kindlin-2^+/− ECs compared with WT ECs. Images of ECs forming tubes taken at 1, 3, and 6 hours are shown and are representative of 2 independent experiments including 6 individual EC samples per group (6 mice per group).