DEPARTAMENTO DE CIÊNCIAS DA VIDA ... - Estudo Geral

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Figure 12 - MSCs cultured on 1 and 11 kPa static (top) and gradient (bottom) hydrogels and stained for
B-III- tubulin (red) (neuronal marker) and MyoD (green) (myogenic marker). Open arrowheads indicate
cells expressing either B-III- tubulin or MyoD while filled arrowheads indicate doubly stained cells.
Adapted from Tse and Engler,, 2011.
To study the “memory” of MSCs, Tse and Engler showed that in static
hydrogels, after 7 days, in values of elasticity of 1 and 11 kPa there was expression of
B-III tubulin and MyoD-positive MSCs, respectively, and cells remaining on soft regions
of gradient hydrogels expressed B-III tubulin (Figure 12, open arrowheads). However,
MSCs on the stiffer regions of the gradient displayed a mixed phenotype consisting of
cells positive for MyoD alone (open arrowheads) and those also expressing low
amounts of B-III tubulin (filled arrowheads)(Figure 12). When B-III tubulin and MyoD
fluorescent intensities were quantified and normalized to the non-permissive static
hydrogel, i.e. 11 and 1 kPa hydrogels respectively (Figure 13), MSCs on stiffer regions
had on average a 3-fold higher B-III tubulin fluorescent intensity versus the control
static stiffer hydrogel (11kPa). On the other hand, MSCs on softer regions had less than
a 50% difference in MyoD fluorescence when compared to the cells plated on the
static hydrogel.