Enhanced Unidirectional Cell Migration Induced by Asymmetrical Micropatterns with Nanostructures.

Directed cell migration is crucial for numerous biological processes, including tissue regeneration and cancer metastasis. However, conventional symmetrical micropatterns typically result in bidirectional cell migration guidance instead of unidirectional guidance. In this study, polydimethylsiloxane (PDMS)-based platforms with asymmetrical arrowhead micropatterns, nanopillars, and selective fibronectin coating were developed to enhance unidirectional cell migration. The platforms were fabricated using nanoimprint lithography and PDMS replication techniques, allowing for precise control over surface topography and biochemical modification. The MC3T3 osteoblastic cells cultured on these platforms demonstrated significantly enhanced directional migration, characterized by increased displacement, and directional alignment with micropattern orientation compared to symmetrical patterns. Quantitative analyses revealed that asymmetrical arrowheads combined with nanopillars induced more focal adhesions and F-actin polarization at cell front regions, supporting the observed unidirectional cell migration enhancement. These results confirm that integrating micropattern asymmetry, nanoscale features, and biochemical functionalization synergistically promotes unidirectional cell migration. The developed platforms offer valuable insights and practical strategies for designing advanced biomaterials capable of precise spatial cell guidance that can be applied to the designs of organ-on-a-chip systems.