Biomaterial scaffolds used for the regeneration of spinal cord injury (SCI)

This review presents a summary of various types of scaffold biomaterials used alone or together with therapeutic drugs and cells to regenerate spinal cord injury (SCI). The inhibitory environment and loss of axonal connections after SCI give rise to critical obstacles to regeneration of lost tissues and neuronal functions. Biomaterial scaffolds can provide a bridge to connect lost tissues, an adhesion site for implanted or host cells, and sustained release of therapeutic drugs in the injured spinal cord. In addition, they not only provide a structural platform, but can play active roles by inhibiting apoptosis of cells, inflammation and scar formation, and inducing neurogenesis, axonal growth and angiogenesis. Many synthetic and natural biomaterial scaffolds have been extensively investigated and tested in vitro and in animal SCI models for these purposes. We summarized the literature on the biomaterials commonly used for spinal cord regeneration in terms of historical backgrounds and current approaches.