Stem Cell Differentiation Depending on Different Surfaces - Tissue Engineering: Cell-Surface Interactions for Tissue Culture - page 272

Fig. 2 Scanning electron microscopy images from adipose-derived mesenchymal stem cells
(left) and umbilical cord mesenchymal stem cells (right) cultivated for 5 weeks on a macroporous
ZrO 2 biomaterial (Sponceram, Zellwerk)
differentiation by an increased rate of lipid production on patterned surfaces with
grooves of 3 lm width, 1.5 lm depth, and 100 lm separation.
Summarizing the publications on the differentiation of MSC influenced by
surface topography, we conclude that surface roughness may be used as an
effective tool to modulate cell differentiation.
4.4 Geometry
Cells can sense not only the stiffness or roughness of their underlying substrate, but
also the edges of their microenvironment. This so-called pattern edge phenomenon
influences cell division, cell migration, and the cytoskeleton dynamics [ 66 , 67 ].
Nevertheless, the influence of two-dimensional substrate geometries on stem
cell differentiation has rarely been examined. Wan et al. [ 68 ] hypothesized that
stem cell proliferation and differentiation is directed through position-defined
mechanical stress and the resulting morphological cell changes. To prove their
hypothesis they cultivated human adMSC on different two-dimensional patterns
(rings with different diameters and rectangles with differing sizes). Osteogenic and
adipogenic differentiation occurred in the same regions depending on the medium,
containing cells with a small and elongated morphology. Within the ring patterns
differentiation decreased with the radius from the inner to the outer ring, where
mostly large spreading cells were observed. Differentiation within the rectangles
occurred mainly close to the short-axis edge. Finally, it can be stated that the
geometry-derived forces affect cell morphology and cytoskeletal organization,
which direct the stem cell proliferation and differentiation. Proliferation may be
inhibited and differentiation may be induced by low levels of cytoskeletal tension
due to increased cell-cell contacts. Similar results have been obtained by [ 23 ].