In Situ, Light-Guided Axon Growth on Biomaterials via Photoactivatable Laminin Peptidomimetic IK(HANBP)VAV

Abstract

The ability to guide the growth of neurites is relevant for reconstructing neural networks and for nerve tissue regeneration. Here, a biofunctional hydrogel that allows light-based directional control of axon growth in situ is presented. The gel is covalently modified with a photoactivatable derivative of the short laminin peptidomimetic IKVAV. This adhesive peptide contains the photoremovable group 2-(4′-amino-4-nitro-[1,1′-biphenyl]-3-yl)propan-1-ol (HANBP) on the Lys rest that inhibits its activity. The modified peptide is highly soluble in water and can be simply conjugated to -COOH containing hydrogels via its terminal -NH 2 group. Light exposure allows presentation of the IKVAV adhesive motif on a soft hydrogel at desired concentration and at defined position and time point. The photoactivated gel supports neurite outgrowth in embryonic neural progenitor cells culture and allows site-selective guidance of neurites extension. In situ exposure of cell cultures using a scanning laser allows outgrowth of neurites in desired pathways.