Template synthesized poly(ɛ-caprolactone) nanowire surfaces for neural tissue engineering

Tissue engineering therapies targeted at nerve regeneration in spinal cord injuries (SCI) have broad social and economic benefits to the American population. Due to the complicated pathophysiology of SCI, there are very few options available for functional regeneration of the spinal column. Nanotechnology offers interesting avenues to explore tissue engineering in SCI. In this study, we have developed a novel solvent free nanotemplating technique for fabricating poly(epsilon-caprolactone) (PCL) surfaces with controlled arrays of high aspect ratio substrate-bound nanowires for the growth and maintenance of differentiated states of neuronal cells. PC12 cells were used to evaluate the ability of nanowire surfaces to promote neuronal phenotypic behavior. Cell adhesion, proliferation and viability were investigated for up to 4 days of culture using fluorescence microscopy, scanning electron microscopy (SEM) and MTT activity. Our results indicate significantly higher cell adhesion and subsequent proliferation and viability of PC12 cells cultured on nanowire surfaces as compared to control surfaces without any nanoarchitecture. Further, the adhered cells were maintained in a differentiated state for 7 days and neuronal network formation and expression of neuronal markers were investigated using fluorescence microscopy, SEM and immunofluorescence. Cells on nanowire surfaces expressed key neuronal markers and demonstrated neuronal phenotypic behavior as compared to the cells on control surfaces.