Figure 6
The functionalized nanofiber substratum potentiates cardiomyocyte differentiation. Human PSCs were cultured over the MEF. To induce cardiomyocyte differentiation, EBs were formed by culturing the PSCs over ultra-low-attachment culture dishes. The same number of EBs were spread and differentiated for 10 d over each of the substratum as depicted in the diagram (a). Laminin-211 indicates laminin-211-coated dishes, PEG-AuNP indicates nanofiber substrata containing the PEG-AuNPs, and PEG-AuNP-HBP + cRGD indicates nanofiber substrata containing PEG-AuNPs functionalized with HBP and cRGD. After 10 d of differentiation, cell clumps showing spontaneous contractility appeared. A single cardiomyocyte colony was defined as a cell clump showing synchronized beating (black outlined), irrespective of its size (b). Cardiomyocyte colonies generated in 3 dishes of each substratum were counted for quantification (c). Scale bars: 500 μm. Error bars: SEM, n = 3. The asterisks indicate statistical significance (P < 0.01) calculated using the Student t test. The results shown represent 3 independent experiments. PSC: pluripotent stem cell, MEF: mouse embryonic fibroblast, EB: embryoid body, Growth: growth medium, and Differentiation: differentiation medium.