| The physical environment is fundamentally important in determining cellular behavior. I present research that is focused on changing the nano- and micro-environment of cultured primary cortical neurons. I developed a lithography-free methodology, notable for its simplicity, to create 2-D biochemical micropatterns and 3-D anisotropic grooved topographical features of various dimensions to guide and direct neuronal outgrowth. In particular, axonal outgrowth was found to orient parallel to lines of 8.3 micron periodicity, but perpendicular to lines of 1.7 micron periodicity. By superimposing topographical and chemical cues, it was found that topographical modification could enhance or inhibit outgrowth perpendicular to topography, depending on the combination scheme. By decreasing the topographical feature radius of curvature, axons could be induced to transition from a perpendicular to a parallel guidance relative to the topography. Also, neurons and glial cells could be made in co-culture to align parallel or perpendicular to each other. Work is continuing to determine the biophysical mechanisms which control the outgrowth process, which knowledge will form an integral part of our understanding of the nervous system. |
