Interaction of embryonic cortical neurons on nanofibrous scaffolds for neural tissue engineering

The interaction of murine embryonic cortical neurons on randomly orientated electrospun scaffolds of poly(L-lactide)(PLLA)and poly(lactide-co-glycolide)(PLGA)is investigated in this study. The scaffolds were surface treated with different concentrations of KOH to partially hydrolyze the surface and therefore change the surface tension. Hydrophilicity did not significantly influence the number of primary and secondary branches; however, it had a considerable effect on neurite extension. For scaffolds with surface tensions of 40- 47 dyn cm.1 there was a significantly greater overall neurite length for both the primary and secondary branches compared with more hydrophilic scaffolds. Another major finding of this work was that the interfibre distance influenced how the neurites extended. When the interfibre distance was greater than approximately 15 ìm the neurites followed the fibres and avoided regions of very high fibre density. At interfibre distances less than approximately 15 ìm, the neurites traversed between the fibres. Therefore, this study provided little evidence that contact guidance was the dominating cue in directing neurite extension, instead inferring that chemical cues, possibly from adjacent neurons had induced directional change.