In vitro wrinkle formation via shape memory dynamically aligns adherent cells

Surface wrinkling of materials offers a simple yet elegant approach to fabricating cell culture substrates with highly ordered topographies for investigating cell mechanobiology. In this study we present a tunable shape memory polymer (SMP) bilayer system that is programmed to form, under cell compatible conditions, wrinkles with feature sizes on the micron and sub-micron length scale. We found that with increasing deformation fixed into the SMP substrate, wrinkled topographies with increasing amplitudes, decreasing wavelengths, and increasing degree of wrinkle orientation were achieved. Analysis of the cellular response to previously wrinkled (static) substrates revealed that cell nuclear alignment increased as SMP deformation increased. Analysis of the cellular response to an actively wrinkling substrate demonstrated that cell alignment can be controlled by triggering wrinkle formation. These findings demonstrate that the amount of deformation fixed (and later recovered) in an SMP bilayer system can be used to control the resulting wrinkle characteristics and cell mechanobiological response. The tailored and dynamic substrate functionality provided by this approach is expected to enable new investigation and understanding of cell mechanobiology.