Anisotropic Multi-channel Collagen Gel (MCCG) Guides the Growth Direction of the Neurite-like Processes of PC12 Cells.

Hydrogels made of various materials using a variety of methods have been extensively studied for use in tissue engineering, and collagen is one of the most common material used for its biocompatibility due to it being a major component of the extracellular matrix (ECM). Furthermore, the alignment of collagen fibres has been shown to direct the growth of neurites, an important criterion for engineering nervous tissues. The Multi-channel Collagen Gel (MCCG) has collagen fibres aligned circumferentially around the channel structures of the gel, and we predicted that the MCCG could guide the growth direction of neurites. In this study, we showed that the growth pathway of the neurite-like processes of PC12 cells were guided in MCCG but not in normal collagen gel (COL). The gelation of collagen gels are known to be affected by ionic concentrations, and hence we also investigated the effects of different concentrations of NaCl on the properties of MCCG. We found that, despite differences in channel density, spacing between channels, and degree of collagen fibre alignment, all MCCGs had similar guiding properties on the growth of neurites. Therefore, we believe that anisotropic MCCG could be a useful biomaterial for neural tissue engineering in the future.