Peripheral Nerve Regeneration

Several advances in nerve cell culture, development of new biomaterials, and genetic techniques have led to the introduction to innovative techniques for nerve regeneration. Analytically, natural or artificial grafts used to bridge nerve gaps have four central components germane to regeneration: scaffold/substrate, growth factors, extracellular matrix (ECM) molecules, and cells. A graft might have a combination or all of the four components. The grafts are classified as isotropic or anisotropic on the basis of distribution of these four components within the graft. In isotropic grafts, the components are distributed uniformly within the graft, with no directional cues. In anisotropic grafts one or more of these components are distributed anisotropically, usually along the direction of regeneration, to direct the axonal growth towards the distal target. Isotropic natural materials used as scaffolds include veins, skeletal muscle fibers, and collagen, and synthetic scaffolds are advantageous because they can be tailored in terms of their mechanical, chemical, and structural properties to augment nerve regeneration. Several anisotropic scaffolds are fabricated to affect neuronal behavior. Neuronal-growth supporting cells could be incorporated with longitudinally aligned filaments and gels in nerve guidance conduits (NGCs) to enhance nerve regeneration. Biodegradable conduits of a copolymer of lactic and glycolic acids (PLGA) with longitudinally aligned channels are used for nerve regeneration. The channels, with the lumen coated with laminin, and seeded with Schwann cells, show regeneration comparable to nerve autografts over a 7-mm nerve gap in rats. © 2011 Elsevier Inc. All rights reserved.

Duke Scholars

Author Ravi Venkat Bellamkonda Biomedical Engineering