If no planar spreading occurs the dominant dislocations are determined by their energy.
The functionalized microtubes offer a cell culture environment where the cells can form adhesions to the substrate all around the cell body so that a transition from a planar and spread to a more 3D morphology occurs.
The maximum spread planar projection (Figure 1A) exhibits a prominent "U-shape" resulting from a bimodal distribution along the first dimension and a unimodal distribution along the second.
The map geometric characteristics include a limited number (∼4) of statistically significant dimensions, a bimodal distribution of the first component, increasing kurtosis of subsequent (unimodal) components, and a U-shaped maximum-spread planar projection.
In contrast, cells on planar glass were freely spread (2-D migration) without the contribution of traction force between the substrates and the cells.
These observations may go some way to explain the requirement for C/EBPδ for proper adhesion and spreading on planar and nanometric growth surfaces described in Fig. 1.
With further increasing incubation time to 45 h, the A549 cells cultured on planar glass substrates were well spread over the substrates, while the spreading behaviors of the cells on the two types of nanostructures were completely limited in the spreading area as indicated in Figure2a (third column).
From these experiments it was apparent that MEF WT cells spread normally on planar growth surfaces, possessing a well developed actin cytoskeleton and adhesion complexes, as indicated by phalloidin and vinculin staining respectively.
Cells cultured on planar controls showed a near uniformly spread morphology with significantly fewer focal complexes (associated with cellular spread) and more mature adhesions than on grooved substrates.
c Final hole surrounded by an AlAs wall and planar AlAs layer caused by spreading of the initial droplet material.
