Cellular Activity and Biomaterial's Surface Topography

The contact of a cell on the biomaterial’s surface is mediated by its adhesion components. The topography of titanium surfaces influences these adhesion components of osteoblasts, e.g. the integrins, the adapter proteins and the actin cytoskeleton. In our current experiments we were interested in why osteoblasts were strongly aligned to the grooves of a structured pure titanium surface (grade 2). The titanium was characterized by EIS to get insights in the electro-chemically active surface. We used MG-63 human bone cells, cultured in DMEM with 10% FCS at 37°C. For protein adsorption the titanium discs were incubated for 24h with complete medium containing soluble fibronectin at 37°C. Interestingly, only in the grooves cells adhered and were aligned and this is not dependent on the gravitation. The cell adhesion seems to depend on the protein adsorption of fibronectin which we could find to be adsorbed exclusively in the valleys. We speculate that there are local differences in electro-chemical characteristics of this structured titanium surface.