Enhanced survival of neural cells embedded in hydrogels composed of collagen and laminin-derived cell adhesive peptide.

To develop biomaterials that serve to improve the survival of neural cells transplanted into central nervous tissues, type I collagen-based hydrogels were prepared as a cell carrier. The hydrogels were modified with a laminin-derived peptide that is known to have an affinity for alpha3beta1 integrin, to transduce antiapoptotic signaling in embedded cells. For the modification of collagen, the peptide was fused to the N- or C-terminus, or both termini of a collagen-binding polypeptide domain by means of recombinant DNA technology. The chimeric proteins were characterized by polyacrylamide gel electrophoresis and circular dichroism spectroscopy, while binding of chimeric proteins to collagen-coated substrates was verified by surface plasmon resonance analysis under physiological conditions. Cell culture assays revealed that the adhesion of neurosphere-forming cells to collagen-coated polystyrene surfaces was significantly promoted by the incorporation of the chimeric proteins in a peptide-density dependent manner. The live/dead assays for cells cultured for 24 or 48 h in the hydrogels revealed that peptide incorporation improved the survival of cells embedded in collagen hydrogels. These results suggest that collagen hydrogel containing the laminin-derived peptide provides microenvironments suitable for the survival of neural cells.