Neuronal Electrophysiological Function and Control of Neurite Outgrowth on Electrospun Polymer Nanofibers Are Cell Type Dependent

Modeling of cellular environments with nanofabricated biomaterial scaffolds has the potential to improve the growth and functional development of cultured cellular models, as well as assist in tissue engineering efforts. An understanding of how such substrates may alter cellular function is critical. Highly plastic central nervous system hippocampal cells and non-network forming peripheral nervous system dorsal root ganglion (DRG) cells from embryonic rats were cultured upon laminin-coated degradable polycaprolactone (PCL) and nondegradable polystyrene (PS) electrospun nanofibrous scaffolds with fiber diameters similar to those of neuronal processes. The two cell types displayed intrinsically different growth patterns on the nanofibrous scaffolds. Hippocampal neurites grew both parallel and perpendicular to the nanofibers, a property that would increase neurite-to-neurite contacts and maximize potential synapse development, essential for extensive network formation in a highly plastic cell type. In contrast, non-network-forming DRG neurons grew neurites exclusively along fibers, recapitulating the simple direct unbranching pathway between sensory ending and synapse in the spinal cord that occurs in vivo. In addition, the two primary neuronal types showed different functional capacities under patch clamp testing. The substrate composition did not alter the neuronal functional development, supporting electrospun PCL and PS as candidate materials for controlled cellular environments in culture and electrospun PCL for directed neurite outgrowth in tissue engineering applications.