DEPARTAMENTO DE CIÊNCIAS DA VIDA ... - Estudo Geral

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Figure 11 - Images of mitomycin C-treated MSCs on gradient hydrogels (with stiffness gradient, ≈1 to
15 kPa) and their spatial distribution. Hoescht 33342 (blue) and phalloidin (red)-stained mitomycin C-
treated MSCs plated at 250 cells/cm 2 , illustrate the change in distribution with time. Scale bar is 56.5
µm. Adapted from Tse and Engler, 2011.
Making a closer approach to the durotaxis, it is described that the actomyosin
cytoskeleton maintains polarized morphology and requires tension for durotaxis. Focal
adhesion complexes at the leading edge of cells likely establish critical intracellular
signaling gradients for durotaxis (Tse and Engler, 2011). It was observed that by 21
days, the center of the hydrogel became locally confluent (Figure 11, right), and
because of the mitomycin C treatment (which inhibits cell proliferation), this was in
fact created by all cells undergoing directed migration to the stiffest region of the
hydrogel (Engler et al. 2006). Durotaxis can also be observed in mitomycin C-treated
MSCs plated at higher densities, i.e. 1000 cells/cm2, and again a loss of cells at the
softest regions and an accumulation of cells at the stiffest regions were observed (Tse
and Engler, 2011).