FIGURE 3.

Phase contrast images of C2C12 cells growing on the IPN-defined patterns at day 4 after plating. Cells recognize the pattern with nearly 100% efficiency. Two myotubes, 1000-μm and 600-μm long, are shown within dashed boxes. Rounded cells (arrows) and the occasional branched myotube (arrowhead) are most likely due to defects in the IPN, and account for 10% of the total cells. Upper inset is a differentiated myotube, and illustrates a cell width, W, that varies by less than a factor of 2 along the entire length of the cell.