Suppression of anoikis by collagen coating of interconnected macroporous nanometric carbonated hydroxyapatite/agarose scaffolds

Three dimensional interconnected macroporous (pore diameter: 600-800 mu m) hydroxyapatite/agarose disks have been evaluated in this study as potential bone regeneration scaffolds. With this purpose, the adhesion and proliferation of human Saos-2 osteoblasts on this biomaterial were analyzed. As an index of cell function, the following parameters were measured: cell morphology, viability, cell size/complexity, cell cycle, reactive oxygen species (ROS) content, and lactate dehydrogenase (LDH) release. The existence of anoikis induced by inappropriate contacts between the cell and the scaffold has been detected by scanning electron microscopy, confocal microscopy, and flow cytometry. The intracellular nitric oxide content has been also measured as potential inducer of anoikis. The positive effects of previous scaffold coating with type I collagen on osteoblast adhesion as well as the collagen protection against anoikis have been demonstrated in this study. (C) 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 95A: 793-800, 2010.