Explanted a) alginate-PLL100, (original magnification 10×).

Note the macrophages and fibroblasts. b) Alginate-PLL100-PEG454-b-PLL50 microcapsules (original magnification 40×). Only a portion of capsules had inflammatory cells at the surface. Note that the affected capsules in most cases had adherence of a few or sometimes clumps of cells instead of complete coverage as in a). This suggests that local imperfections at the capsule's surface may be responsible for cell adhesion. All capsules were retrieved one month after implantation in the peritoneal cavity of balb/c mice GMA-embedded histological sections, Romanovsky-Giemsa staining.