Myotube Assembly on Nanofibrous and Micropatterned Polymers

Skeletal muscle consists of parallel bundles of myotubes formed by the fusion of myoblasts. We fabricated nanofibrous and micropatterned polymers as cell culture substrates to guide the morphogenesis of muscular tissue. The nanoscale and microscale topographic features regulate cell and cytoskeleton alignment, myotube assembly, myotube striation, and myoblast proliferation. This bottom-up approach from nanoscale to tissue level demonstrates the potential of nanofibrous polymers for engineering the assembly of cell and tissue structure. Spatial and geometric signals regulate numerous aspects of cellular and tissue behavior, including proliferation, migra-tion, and regeneration.1 In the case of skeletal muscle, its structure is highly organized and consists of long parallel bundles of multinucleated myotubes that are formed by differentiation and fusion of myoblast satellite cells.2 When cultured in vitro, however, myoblasts and myotubes lose their native organization and adopt random distributions, which do not resemble physiological muscle architecture. To understand the role of spatial cues in regulating skeleta