Crystalline Bacterial Protein Nanolayers for Cell Micropatterning

Abstract

We have developed a robust cell patterning method using micromolding in capillaries (MIMIC) and selfassembled crystalline bacterial protein (S-layer) monolayers. The unique self-assembly properties of proteins SbpA and SbsB are exploited to create an anisotropic protein nanobiointerface with spatially-defined cytophilic (adhesive) and cytophobic (repulsive) properties. The chosen S-layer proteins were characterized using atomic force microscopy (AFM), zeta-potential and contact angle measurements. Results revealed distinct differences in surface topography and physicochemical properties between SbsB and SbpA monolayers. Stability testing of cytophobic protein SbpA using vacuumdrying deposition and re-assembly on-flow sowed no remarkable differences with respect to the antifouling properties. Finally, using MIMIC micropatterns of epithelial CaCo-2 cell as well as mobile Jurkat cells were established using anisotropic S-layer protein monolayers.