The Nanoscale Geometrical Maturation of Focal Adhesions Controls Stem Cell Differentiation and Mechanotransduction

Abstract

We show that the nanoscale adhesion geometry controls the spreading and differentiation of epidermal stem cells. We find that cells respond to such hard nanopatterns similarly to their behavior on soft hydrogels. Cellular responses were seen to stem from local changes in diffusion dynamics of the adapter protein vinculin and associated impaired mechanotransduction rather than impaired recruitment of proteins involved in focal adhesion formation.

Physical and biological characteristics of nanohydroxyapatite and bioactive glasses used for bone tissue engineering

“…The nanoscale architecture of adhesion sites plays an important role for the formation of focal adhesions and their dynamics [169]. A progressive restriction of cell spreading has been reported when comparing substrates with decreasing pattern sizes to homogeneous substrates (Figure 19).…”

“…A progressive restriction of cell spreading has been reported when comparing substrates with decreasing pattern sizes to homogeneous substrates (Figure 19). Therefore, controlling the nanoscale physicochemical properties of the matrix is essential for stem cell expansion and differentiation [169]. In light of this, the role of nanoparticles in altering the surface topography of 3D scaffolds would be an important factor in the success of bone tissue engineering and may require further investigation.…”

FRET-based Molecular Tension Microscopy

“…In HEK cells on T-shaped patterns, a-actinin exhibits high tension is regions that display thick actin stress fibers hanging between cell-adhesive surfaces, and lower tension in regions contacting cell-adhesive surfaces [41]. In primary epidermal keratinocytes, sub-micron adhesive patterns decreased tension on vinculin compared to larger patterns or unpatterned surfaces [44]. In contrast, in pairs of MDCK cells, E-cadherin tension at cell-cell contacts was insensitive to cell-substrate adhesion geometries that nevertheless affected cell traction forces [25].…”

Recent Strategies in Osteochondral Substitutes Design: Towards the Mimicking of a Multifaceted Anatomical Unit from the Nano to the Macro Level

“…One of the underlying mechanisms that make nanomaterials superior to conventional materials for tissue engineering applications is that the former ones exhibit surface properties promoting protein adsorption. This process, favouring cell adhesion, Has a greater chance of stimulating new bone growth when compared to conventional materials [1].…”