Cell attachment behavior on solid and fluid substrates exhibiting spatial patterns of physical properties.

The ability to direct proliferation and growth of living cells using chemically and topologically textured surfaces is finding many niche applications, both in fundamental biophysical investigations of cell-surface attachment and in developing design principles for many tissue engineering applications. Here we address cellular adhesion behavior on solid patterns of differing wettability (a static substrate) and fluid patterns of membrane topology (a dynamic substrate). We find striking differences in the cellular adhesion characteristics of lipid mono- and bilayers, despite their essentially identical surface chemical and structural character. These differences point to the importance of subtle variations in the physical properties of the lipid mono- and bilayers (e.g., membrane tension and out-of-plane undulations). Furthermore, we find that introducing phosphatidylserine into the patterned lipidic substrates causes a loss of cell-patterning capability. Implications of this finding for the mechanism by which phosphatidylserine promotes cellular adhesion are discussed.