Figure 1.

Targets of combined biomaterial-supported cell transplantation following SCI. SCI induced neural damage leads to severed connections, tissue loss and the appearance of a cystic cavity. Combined biomaterials and cell transplantation can be used to fill the lesion cavity to provide physical support and bridge the distance that regrowing axons must traverse. Cell transplantation as well as newly introduced neurotrophic factors may provide trophic support (secreted growth factors) supporting axonal growth. An immune reaction, consisting of activated microglia, macrophages, fibroblasts and astrocytes, is elicited following injury to close off and prevent the spread of damage as well as re-establish the blood-spinal-barrier, possibly obstructing axonal regrowth. Additionally, neural injury leads to the release of growth inhibitory components [myelin debris, inflammatory cytokines, and chondroitin sulfate proteoglycans (CSPG)] that can be down regulated by either cell transplantation or the release of biomolecules into the lesion site.