Spatial control of embryo blood vessel formation on the patterned side membranes.

<p>The total oxygen volume permeating into each cubic eggshell was calculated to be comparable to that of cubic eggshells fabricated from six 0.3-mm-thick PDMS membranes. (a) Typical images of blood vessel formation in oxygenated channels with widths of 5, 10, and 16 mm, respectively. Polystyrene plates were glued on a 0.1-mm-thick PDMS membrane to make an oxygen non-permeable (NP) area. From day 4 to 7, blood vessels grew selectively in the oxygen-permeable channels. (b) Area ratios of blood vessels on a whole lateral-side membrane (width: 32 mm) made from a 0.3-mm-thick membrane and in the channels with widths of 5, 10, and 16 mm (0.1-mm-thick membrane). From day 4 to 7, the area of blood vessel formation decreased prominently in the narrow channel because of the decrease of oxygenated area on the patterned lateral-side membrane. (c) Height ratios of the area of blood vessel formation from day 4 to 7. On a whole lateral-side membrane or in the oxygenated channel with a width of 16 mm, blood vessels spread rapidly after the transferring of egg contents. On the other hand, blood vessels grew slowly in the oxygenated channel with a width of 5 mm. The error bar is SEM (n = 5). The detailed process of image analysis and definition of <i>A</i>_<i>b</i> and <i>H</i>_<i>b</i> are shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0118624#pone.0118624.s004" target="_blank">S4 Fig.</a>