Nanoscaled surface patterning is an emerging potential method of directing the fate of stem cells. We adopted nanoscaled pillar gradient patterned cell culture plates with three diameter gradients [280-360 (GP 280/360), 200-280 (GP 200/280), and 120-200 nm (GP 120/200)] and investigated their cell fate-modifying effect on multipotent fetal liver kinase 1-positive mesodermal precursor cells (Flk1+ MPCs) derived from embryonic stem cells. We observed increased cell proliferation and colony formation of the Flk1+ MPCs on the nanopattern plates. Interestingly, the 200-280 nm-sized (GP 200/280) pillar surface dramatically increased cardiomyocyte differentiation and expression of the early cardiac marker gene Mesp1. The gradient nanopattern surface-induced cardiomyocytes had cardiac sarcomeres with mature cardiac gene expression. We observed Vinculin and p-Cofilin-mediated cytoskeleton reorganization during this process. In summary, the gradient nanopattern surface with 200-280 nm-sized pillars enhanced cardiomyocyte differentiation in Flk1+ MPCs.
Keywords: Flk1-positive mesodermal precursor cells; cardiomyocyte differentiation; cytoskeleton reorganization; gradient nanopattern plates; nanoimprinting.