Patterning of two-level topographic cues for observation of competitive guidance of cell alignment.

Cells display contact guidance when cultured on topographical cues. By combining standard photolithography, nanoimprint lithography, and soft lithography, we produced sophisticated patterns on two levels, including crossing microgrooves with different depth/spacing and microgrooves with superimposed submicrometer features. The results show that for narrowly spaced microgrooves, the contact guidance is more significant to the change of groove depth than to other geometry parameters. For crossing microgrooves, the shallow grooves take over the influence on cell alignment when the deeper grooves are well separated. Finally, the superimposed submicrometer features on the groove ridges decrease the efficiency of the contact guidance of microgrooves, due to increased adhesion of cells on patterned surfaces.