Cell adhesion to protein-micropatterned-supported lipid bilayer membranes

Abstract

A new method for constructing controlled interfaces between cells and synthetic supported lipid bilayer membranes is reported. Microcontact printing is used to define squares and grid lines of fibronectin onto glass, which subsequently direct the self-assembly of fluid lipid bilayers onto the complementary, uncoated regions of the surface. Features of fibronectin as small as 5 microm effectively control the lateral organization of the lipid bilayers. These fibronectin barriers also facilitate the adhesion of endothelial cells, which exhibit minimal adhesion to fluid supported lipid bilayers alone. Cells selectively adhere to the features of fibronectin, spanning over and exposing the cells to the intervening regions of supported lipid bilayer. Cell spreading is correlated with both the geometry and dimensions of the fibronectin barriers. Importantly, lipids underlying adherent cells are laterally mobile, suggesting that, in contrast to the regions of fibronectin, cells were not in direct contact with the supported membrane. Protein micropatterning thus provides a valuable tool for controlling supported membranes and for juxtaposing anchorage-dependent cells with lipid bilayers. These systems should be generally useful for studying specific interactions between cells and biomolecules incorporated into supported membranes, and as an approach for integrating living cells with synthetic, laterally complex surfaces.