Fig. 4. Measuring Cell-Induced Deformations of the Underlying Substrate.
Mean FRET intensity ratio and ratio maps of fibronectin underneath A. spread 3T3s (left) and B. MSCs (right) on low and high acrylic acid PA hydrogels activated with EDC/NHS and coated with dual-labeled fibronectin. (n > 16; mean ± S.E.M.; **p < 0.01; ***p < 0.005). C. Displacement maps of embedded fluorescent particles (left) and D. mean particle displacement (right) resulting from 3T3 and MSC tractions exerted on low and high acrylic acid PA hydrogels activated with EDC/NHS and coated with collagen type I. (n = 25; mean ± S.E.M.; ***p < 0.005).