title: Preparation of uniaxial multichannel silk fibroin scaffolds for guiding primary neurons.
abstract: Physical guidance cues have been exploited to stimulate neuron adhesion and neurite outgrowth. In the present study, three-dimensional (3-D) silk fibroin scaffolds with uniaxial multichannels (42-142 μm in diameter) were prepared by a directional temperature field freezing technique, followed by lyophilization. By varying the initial silk fibroin concentration, the chemical potential and quantity of free water around cylindrical ice crystals could be controlled to control the cross-section morphology of the scaffold channels. Aligned ridges also formed on the inner surface of the multichannels in parallel to the direction of the channels. In vitro, primary hippocampal neurons were seeded in these 3-D silk fibroin scaffolds with uniaxial multichannels of ∼120 μm in diameter. The morphology of the neurons was multipolar and alignment along the scaffold channels was observed. Cell-cell networks and cell-matrix interactions established by newly formed axons were observed after 7 days in culture. These neurons expressed β-III-tubulin, nerve filament and microtubule-associated protein, while glial fibrillary acidic protein immunofluorescence was barely above background. The ridges on the inner surface of the channels played a critical role in the adhesion and extension of neurons by providing continuous contact guidance. These new 3-D silk scaffolds with uniaxial multichannels provided a favorable microenvironment for the development of hippocampal neurons by guiding axonal elongation and cell migration.
authors.affiliation: National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Industrial Park, Suzhou, PR China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Yahong
authors.initials: Y
authors.lastname: Zhao
authors.forename: Shuqin
authors.initials: S
authors.lastname: Yan
authors.forename: Yumin
authors.initials: Y
authors.lastname: Yang
authors.forename: Huijing
authors.initials: H
authors.lastname: Zhao
authors.forename: Mingzhong
authors.initials: M
authors.lastname: Li
authors.forename: Shenzhou
authors.initials: S
authors.lastname: Lu
authors.forename: David L
authors.initials: DL
authors.lastname: Kaplan
mesh_terms: D000818:Animals; D012831:Bombyx; D001854:Bone Marrow Cells / Q000166:cytology; D002448:Cell Adhesion / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D018920:Coculture Techniques; D005349:Fibroins / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology / Q000648:ultrastructure; D005615:Freezing; D048091:Guided Tissue Regeneration / Q000379:methods*; D006624:Hippocampus / Q000166:cytology; D008968:Molecular Conformation; D009474:Neurons / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D016062:Porosity / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D017550:Spectroscopy, Fourier Transform Infrared; D017154:Stromal Cells / Q000166:cytology / Q000187:drug effects; D054457:Tissue Scaffolds / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D005349:Fibroins