A nanofibrillar prosthetic modified with fibroblast growth factor-2 for spinal cord repair

Thousands of new cases of spinal cord injury occur each year in the USA alone. However, despite recent advances, there is at present no cure for the resulting paraplegia or quadriplegia. This chapter evaluates a spinal cord prosthetic (SCP) developed in our laboratoy that is comprised of longitudinally bundled strips of nanofibers whose surfaces have been modifed with fibroblast growth factor-2 (FGF-2). The SCP is designed to be a prefabricated implant that can be grafted into the lesion site not only to provide structural but also to provide chemical cues that permit regenerating axons to cross the lesion site. For a comparative study, two separate SCPs were produced with one containing unmodified nanofibers and the other containing FGF-2-modified nanofibers. Both SCPs correctly guided regenerating axons across the injury gap created by an over-hemisection to the adult rat thoracic spinal cord and encouraged revascularization of the injury site. Neither SCP initiated glial scarring when implanted into the injured rat spinal cord. However, devices that incorporated nanofibers modified with FGF-2 encouraged more axonal regrowth and significantly better functional recovery than did devices that incorporated unmodified nanofibers as assessed using the Basso, Beattie, Bresnahan (BBB) locomotor rating scale. As such, the FGF-2-modified SCP provides a multifaceted approach to spinal cord repair.