Cell adhesion ligands allow neurite extension on polyethylene glycol hydrogels

The effect of cell adhesion ligands (RGDS, IKVAV, YIGSR) incorporated into polyethylene glycol hydrogels on neurite extension from PC12 cells was examined. Cells were able to adhere to and extend neurites on hydrogels with the adhesion ligands covalently incorporated in them, but not on hydrogels with the non-adhesive control ligand, RGES, incorporated. This indicates that the adhesion and neurite extension were due to the presence of the adhesion ligand. After two days, more cells extended neurites on hydrogels with RGDS than IKVAV. Further, similar numbers of cells extended neurites on hydrogels with RGDS and on hydrogels with a combination of RGDS and IKVAV. Further studies will include examining more cell adhesion ligands and neurite extension from both PC12 cells and dorsal root ganglia seeded inside proteolytically degradable hydrogels with cell adhesion ligands incorporated. Such bioactive hydrogels may be able to serve as nerve guidance conduits for peripheral nerve regeneration.