Effect of bi-directional microfabricated topographical cues on cellular behavior of mammalian cell line

The study of cell migration is valuable for the understanding of various physiological and pathological processes. Microgrooved/microridged substrates have been intensively studied to reveal the effect of single topographical cues on cellular behavior. However, cells in vivo are usually surrounded by multidirectional topography signals. This study investigated the effect of bi-directional topographical cues on cellular behavior of mammalian cells. In this study, bi-directional pit patterned poly(dimethylsiloxane) (PDMS) substrates were fabricated with different sizes but same depth (1 μm). The fabricated patterns were then used to study cellular response to bi-directional cues of mammalian cell line, in this case HeLa cells. After seeding cells for 48 h, the PDMS substrates were examined by SEM. Cell alignment angle and aspect ratio were measured from the SEM images. The results show that the cells on the patterned substrates with square pits did not align along either x- or y-axis. However the patterns with rectangular pits could promote cell alignment along the longer sides of pits. Moreover, comparing to the cell elongation on the control flat substrate, the elongation of cells was decreased on all the patterned substrates. These results are helpful for a deeper understanding of the mechanism of bi-directional topographical cues on cellular behavior of mammalian cell line.