Nerve growth factor (NGF) [130–136], glial cell line-derived neurotrophic factor (GDNF) [137–142], brain derived neurotrophic factor (BDNF) [141, 143–145] and neurotrophin-3 (NT-3) [90, 135, 141, 146–148] have all been added to biomaterials to treat TBI as well as neurodegenerative disorders spinal cord injuries and peripheral nerve injuries. This evidence concerns the gene NTF3 and spinal cord injury.