Silk 3D matrices incorporating human neural progenitor cells for neural tissue engineering applications

The fabrication of cytocompatible and porous three-dimensional (3D) biomaterial scaffolds is one of the main goals of neural tissue engineering. Silk fibroin 3D scaffolds from mulberry and non-mulberry silks were designed to bridge the tissue gap and provide structural support to maintain the native function of the normal tissues. The microstructure of the fabricated fibroin scaffolds was evaluated which revealed relatively homogeneous pore structure and interconnectivity. The pore sizes and porosity of the scaffolds ranged from 105 to 112 mu m and from 90 to 95%, respectively. The 3D scaffolds were examined by culturing human neural progenitor cells, which demonstrated good cell viability and proliferation over 14 days. The cell culture, hematoxylin-eosin and immunocytochemical results demonstrate that the matrices provided cytocompatibility, good cell morphology and maximum matrix deposition, with the 3D silk-based scaffolds designed from both sources producing comparable results. Although not significantly different, non-mulberry silk matrices appeared to promote slightly increased cell proliferation and matrix deposition. These results indicate that the silk matrices may serve as potential biomaterials for neural regeneration and tissue engineering applications.