FIG. 2.

NSCs survive (a–c) and proliferate (d) in alginate regardless of the compositions tested. Viability of the cells is initially reduced after encapsulation, but significantly improves for all conditions after 1 week (a). Cells are labeled with Hoechst (blue), and propidium iodide (red) stains nuclei of cells with compromised membranes indicative of cell death (b–c). Images of G-encapsulated cells at 21 days illustrate the vulnerability of cells in the center of larger proliferating neurospheres to necrosis, presumably due to reduced nutrient and oxygen diffusion (b–c). NSCs proliferate irrespective of alginate composition, and cell number was significantly increased 21 days postencapsulation over initial 4-day quantities (d). Values were initially nondetectable by the MTS assay 1 day after encapsulation (d). M-PLL capsules were too mechanically unstable to assay after the first week. ^†Significantly increased versus 1 and 4 day values at the 0.05 level (ANOVA). Mean ± standard error of the mean (SEM) is shown. Scale = 100 μm. Color images available online at www.liebertonline.com/ten.