Time-dependent impact of texture sensing and adhesion on guided epithelial cell migration

Cell motion is governed by internal factors, such as the actin cytoskeleton and molecular signaling pathways, but can also be influenced by external factors, such as topography and chemical signaling. These factors are often mediated by the cell's interaction with the extracellular matrix through, for instance, the sensing of chemicals or rigidity. These factors all influence the direction and extent of cell migration and actin cytoskeleton dynamics. The actin cytoskeleton has been shown to be one of the primary sensors of topography, and in the case of ridges, this sensing can be linked with altered cell guidance. We have investigated the interplay among three processes: sensing of, adhesion to, and guidance by the microenvironment. To explore this interplay, we study the migration and actin dynamics of MCF10A cells on a nanoridge surface coated with varying levels of Collagen IV. With increased Collagen IV concentration, we find that cells are more adherent and that the actin dynamics responds to the nanotopography more strongly. However, we find that the enhanced actin behavior does not distinguish between the separate guidance phenotypes. Finally, we observe that collagen-coated surfaces cause cells to travel large distances of up to 100 microns in straight paths despite the bidirectional bias in actin polymerization.