Crystalline Bacterial Protein Nanolayers for Cell Micropatterning

We have developed a robust cell patterning method using micromolding in capillaries (MIMIC) and self-assembled 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 vacuum-drying 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.