Nanoscale Matrix Topography Influences Microscale Cell Motility through Adhesions, Actin Organization, and Cell Shape

Mammalian cells are exposed to complex microenvironments of varying micro- and nanoscale structural features. These multiscale extracellular cues dictate important aspects of cell behavior, including migration, proliferation and differentiation. In this study, we fabricated anodized aluminum oxide (AAO) membranes of either 80 or 40 nm pore diameters. We utilized these membranes as extracellular matrix scaffolds to culture NIH-3T3 fibroblast cells and investigated how the surface nanotopography might regulate their motility. We observed faster and more persistent fibroblast migration on AAO membranes with larger pores. Through various cell-matrix interaction markers, we found that the surfaces with higher nanoporosity enhance motility through larger focal adhesions, aligned actin fibers, and polarized cell morphology. Our findings reveal the importance of nanoscale topographical cues present in the matrix environment in regulating submicrometer-scale subcellular mechanisms of stress fiber organization and adhesion formation, micrometer-scale cell-matrix interactions, and cell motility over hundreds of micrometers.