title: Silk fibroin scaffolds with inverse opal structure for bone tissue engineering.
abstract: How scaffold porosity, pore diameter and geometry influence cellular behavior is-although heavily researched - merely understood, especially in 3D. This is mainly caused by a lack of suitable, reproducible scaffold fabrication methods, with processes such as gas foaming, lyophilization or particulate leaching still being the standard. Here we propose a method to generate highly porous silk fibroin scaffolds with monodisperse spherical pores, namely inverse opals, and study their effect on cell behavior. These silk fibroin inverse opal scaffolds were compared to salt-leached silk fibroin scaffolds in terms of human mesenchymal stem cell response upon osteogenic differentiation signals. While cell number remained similar on both scaffold types, extracellular matrix mineralization nearly doubled on the newly developed scaffolds, suggesting a positive effect on cell differentiation. By using the very same material with comparable average pore diameters, this increase in mineral content can be attributed to either the differences in pore diameter distribution or the pore geometry. Although the exact mechanisms leading to enhanced mineralization in inverse opals are not yet fully understood, our results indicate that control over pore geometry alone can have a major impact on the bioactivity of a scaffold toward stem cell differentiation into bone tissue. © 2016 The Authors Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2074-2084, 2017.
authors.affiliation: Department of Materials, Complex Materials, ETH Zurich, 8093, Zurich, Switzerland.
authors.forename: Marianne R
authors.initials: MR
authors.lastname: Sommer
authors.affiliation: Department of Health Science and Technology, Institute for Biomechanics, ETH Zurich, 8093, Zurich, Switzerland.
authors.forename: Jolanda R
authors.initials: JR
authors.lastname: Vetsch
authors.affiliation: Department of Materials, Complex Materials, ETH Zurich, 8093, Zurich, Switzerland.
authors.forename: Jessica
authors.initials: J
authors.lastname: Leemann
authors.affiliation: Department of Health Science and Technology, Institute for Biomechanics, ETH Zurich, 8093, Zurich, Switzerland.
authors.forename: Ralph
authors.initials: R
authors.lastname: Müller
authors.affiliation: Department of Materials, Complex Materials, ETH Zurich, 8093, Zurich, Switzerland.
authors.forename: André R
authors.initials: AR
authors.lastname: Studart
authors.affiliation: Department of Health Science and Technology, Institute for Biomechanics, ETH Zurich, 8093, Zurich, Switzerland.|Department of Biomedical Engineering, Eindhoven University of Technology, 5600MB, Eindhoven, the Netherlands.|Institute for Complex Molecular Systems, Eindhoven University of Technology, 5600MB, Eindhoven, the Netherlands.
authors.forename: Sandra
authors.initials: S
authors.lastname: Hofmann
mesh_terms: D001842:Bone and Bones / Q000166:cytology / Q000378:metabolism*; D002454:Cell Differentiation; D002478:Cells, Cultured; D005349:Fibroins / Q000737:chemistry*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D010012:Osteogenesis; D016062:Porosity; D023822:Tissue Engineering; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D005349:Fibroins
keywords: bone tissue engineering; human mesenchymal stem cells; porous structure; scaffold; silk fibroin