Using magnetic and topographical cues to influence the growth of neuron extensions

Abstract

The regeneration of damaged nerves is the starting point in many nervous system injury repairs. While nerve autografts are the current gold standard in this regard, biomedical engineers are looking to develop a new technology that eliminates the need for a second surgery with additional complications seen in autografts. This thesis investigates the use of topographical and magnetic growth cues to improve neuronal outgrowth and directional alignment. To determine how a magnetic field could influence neurite extension from dorsal root ganglia (DRG) neurons, a magnetic stimulation apparatus was designed and tested with multiple field strengths and directionalities. After 3 days with 1-hour low-strength static magnetic field stimulation, overall neurite outgrowth was increased by up to 152%. To identify how topographical cues and magnetic stimulation work in tandem to influence neuronal growth, a wire mesh assembly device was designed and tested with magnetically conductive and control glass wires. Wire meshes with random and aligned wire samples were designed and seeded with DRG. Neurites followed along wire "pathways", resulting in aligned neuronal extensions. The combination of the two growth cues then are proposed to lead to improvements in both neuronal outgrowth and alignment, which may lead to improved nerve repair strategies.--Author's abstract