Fig. 5.

Softening is dependent on cell–probe distance at T=32 h. Spatially varying viscoelasticity was measured for the softened matrix of fibroblasts with an initial density of 0.5 M cells/mL. a Relative modulus is significantly below the control value at the cell–probe distance of r < 15 $\mu$m, and increases significantly with r ($\ast Pr<0.05$, Pearson’s test, n=17; trend shown as solid red line). Thus, a softening gradient inward to the fibroblast cells exists. b The mean loss tangent has spatially an insignificantly elevated level (n.s. Pr > 0.05, unpaired t-test; n=16; dotted red line), and an insignificant trend against r (n.s. Pr > 0.05, Pearson’s test, n=16). SDs are indicated by the error bars