(114a) Engineering Advanced Materials for Neural Regeneration

Damage to peripheral nerve and spinal cord tissue can have a devastating impact on the quality of life for individuals suffering from nerve injuries. Our research broadly encompasses analyzing and designing natural-based and electrically conducting biomaterials that can interface with neurons to stimulate and guide nerves to regenerate. This talk will specifically address our work on natural-based biomaterials for both peripheral nerve and spinal cord applications.

To foster peripheral nerve regeneration, we have focused on both “top down” and “bottom up” approaches. For our “top down” approach, we have developed natural acellular tissue grafts created by chemical processing of normal intact nerve tissue to preserve the microarchitecture of the extracellular matrix (ECM) and to eliminate the immune response by removing cell components. This research is the foundation for the Avance Nerve Graft from AxoGen, which is now widely used in clinics for peripheral nerve injuries. In a parallel “bottom up” approach, we have developed advanced hyaluronan-based scaffolds for nerve regeneration applications. Hyaluronic acid (HA; also known as hyaluronan) is a non-sulfated, high molecular weight, glycosaminoglycan found in all mammals; it is a major component of the extracellular matrix in the nervous system and plays a significant role in wound healing and tissue regeneration. Our group has devised novel techniques to process HA into forms for use in peripheral nerve repair applications. For example, have explored advanced laser-based processes, in situ crystallization, and magnetic particle templating to create microarchitecture within the hyaluronan materials to mimic the native basal lamina of nerve and thus to provide physical and chemical guidance features for regenerating axons. These materials have shown promise for supporting peripheral nerve repair after acute transection injury and for promoting regeneration of axons into close proximity of microelectrodes for potential prosthetics applications.

For spinal cord injury (SCI) applications, we have engineered injectable biomaterials for less invasive application in crush injuries, which are the most prominent form of SCI. In this work, we have solubilized decellularized peripheral nerve tissue to create in situ gelling ECM hydrogels. We show that these materials serve as effective therapeutic agents for SCI in rats and are promising delivery agents for cell transplantation applications.