Dynamics of spreading and alignment of cells cultured in vitro on a grooved polymer surface

We used mechanically embossed polyester films to analyze the dynamics of cell alignment and cell-specific factors modulating the response of Chinese hamster ovary (CHO) cells and of a rat myogenic cell line to the surface topography. The films used had grooves with a periodicity of approximately 750 nm and a depth of 150 nm. Both cell lines responded to the topographical feature. On unpatterned control areas, cells of both lines showed a random distribution with orientation angles close to 45°. Both cell types exhibited an elongated morphology on the patterned surface. CHO cells typically showed bipolar spreading. Their contact area increased almost exclusively along the groove direction. Likewise, freshly seeded rat myoblasts displayed protrusions emerging in parallel with the grooves. However, myoblasts frequently had more than two sites with plasma protrusions pulling the cells along different grooves. They could also develop lamellipodia expanding without a preferred direction and long filopodia.