title: Behaviour of human induced pluripotent stem cell-derived neural progenitors on collagen scaffolds varied in freezing temperature and laminin concentration.
abstract: OBJECTIVE
  Biomaterial technology, when combined with emerging human induced pluripotent stem cell (hiPSC) technology, provides a promising strategy for patient-specific tissue engineering. In this study, we have evaluated the physical effects of collagen scaffolds fabricated at various freezing temperatures on the behavior of hiPSC-derived neural progenitors (hiPSC-NPs). In addition, the coating of scaffolds using different concentrations of laminin was examined on the cells.
  
  
  METHODS
  Initially, in this experimental study, the collagen scaffolds fabricated from different collagen concentrations and freezing temperatures were characterized by determining the pore size, porosity, swelling ratio, and mechanical properties. Effects of cross-linking on free amine groups, volume shrinkage and mass retention was also assessed. Then, hiPSC-NPs were seeded onto the most stable three-dimensional collagen scaffolds and we evaluated the effect of pore structure. Additionally, the different concentrations of laminin coating of the scaffolds on hiPSC-NPs behavior were assessed.
  
  
  RESULTS
  Scanning electron micrographs of the scaffolds showed a pore diameter in the range of 23-232 μm for the scaffolds prepared with different fabrication parameters. Also porosity of all scaffolds was >98% with more than 94% swelling ratio. hiPSC-NPs were subsequently seeded onto the scaffolds that were made by different freezing temperatures in order to assess for physical effects of the scaffolds. We observed similar proliferation, but more cell infiltration in scaffolds prepared at lower freezing temperatures. The laminin coating of the scaffolds improved NPs proliferation and infiltration in a dose-dependent manner. Immunofluorescence staining and scanning electron microscopy confirmed the compatibility of undifferentiated and differentiated hiPSC-NPs on these scaffolds.
  
  
  CONCLUSIONS
  The results have suggested that the pore structure and laminin coating of collagen scaffolds significantly impact cell behavior. These biocompatible three-dimensional laminin-coated collagen scaffolds are good candidates for future hiPSC-NPs biomedical nerve tissue engineering applications.
authors: Department of Stem Cells and Developmental Biology at Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.
authors: Fahimeh
authors: F
authors: Khayyatan
authors: Department of Stem Cells and Developmental Biology at Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.
authors: Shiva
authors: S
authors: Nemati
authors: Department of Stem Cells and Developmental Biology at Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.
authors: Sahar
authors: S
authors: Kiani
authors: Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran.
authors: Shahriar
authors: S
authors: Hojjati Emami
authors: Department of Stem Cells and Developmental Biology at Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.
authors: Hossein
authors: H
authors: Baharvand
keywords: Collagen; Laminin; Neural Progenitors; Tissue Engineering