Multiscale, hierarchical topography for systematic investigation of cardiomyocytes differentiation

Abstract

The fate of stem cells is determined by biochemical and biophysical cues that mimics the niche environments. Especially, as the micro/nanopatterning techniques are advanced, the topographical features have been widely studied to regulate the stem cell behaviors. In this study, we developed a multiscale hierarchical substrate (MHS) platform containing the nanopillar and microwrinkle. The MHS could enhance the cardiomyoblast differentiation of H9c2 by providing both microscale and nanoscale spatial controls to facilitate the cell elongation with alignment and the formation of focal adhesion. The platform was fabricated by nanopillar formation by the RIE etching of polystyrene sheets followed by simple wrinkling process. The nano- and micro dimensions can be independently tuned in a wide range. Through it, we could optimize the size of each component good for the cells. Intriguingly, we firstly observed the distinct alignment tendencies according to the obvious wrinkle wavelength differences. The cells were aligned attached on the ridge for the MWS under 12 μm wavelength, on the other hand, the cells were confined within the groove for the MWS above 12 μm. Taken together, by controlling the nano- and micro feature sizes independently, MHS platform can improve the cardiomyoblast differentiation through systematic investigation.