title: Combinatorial scaffold morphologies for zonal articular cartilage engineering.
abstract: Articular cartilage lesions are a particular challenge for regenerative medicine strategies as cartilage function stems from a complex depth-dependent organization. Tissue engineering scaffolds that vary in morphology and function offer a template for zone-specific cartilage extracellular matrix (ECM) production and mechanical properties. We fabricated multi-zone cartilage scaffolds by the electrostatic deposition of polymer microfibres onto particulate-templated scaffolds produced with 0.03 or 1.0mm(3) porogens. The scaffolds allowed ample space for chondrocyte ECM production within the bulk while also mimicking the structural organization and functional interface of cartilage's superficial zone. Addition of aligned fibre membranes enhanced the mechanical and surface properties of particulate-templated scaffolds. Zonal analysis of scaffolds demonstrated region-specific variations in chondrocyte number, sulfated GAG-rich ECM, and chondrocytic gene expression. Specifically, smaller porogens (0.03mm(3)) yielded significantly higher sGAG accumulation and aggrecan gene expression. Our results demonstrate that bilayered scaffolds mimic some key structural characteristics of native cartilage, support in vitro cartilage formation, and have superior features to homogeneous particulate-templated scaffolds. We propose that these scaffolds offer promise for regenerative medicine strategies to repair articular cartilage lesions.
authors.affiliation: Department of Materials, Imperial College London, London, UK; Department of Bioengineering, Imperial College London, London, UK; Institute of Biomedical Engineering, Imperial College London, London, UK.
authors.forename: J A M
authors.initials: JA
authors.lastname: Steele
authors.affiliation: Department of Materials, Imperial College London, London, UK; Department of Bioengineering, Imperial College London, London, UK; Institute of Biomedical Engineering, Imperial College London, London, UK.
authors.forename: S D
authors.initials: SD
authors.lastname: McCullen
authors.affiliation: Department of Materials, Imperial College London, London, UK; Department of Bioengineering, Imperial College London, London, UK; Institute of Biomedical Engineering, Imperial College London, London, UK; Institute for Materials and Processes (IMP), School of Engineering, The University of Edinburgh, Edinburgh, UK.
authors.forename: A
authors.initials: A
authors.lastname: Callanan
authors.affiliation: Department of Materials, Imperial College London, London, UK; Department of Bioengineering, Imperial College London, London, UK; Institute of Biomedical Engineering, Imperial College London, London, UK.
authors.forename: H
authors.initials: H
authors.lastname: Autefage
authors.affiliation: Department of Mechanical Engineering, Imperial College London, London SW7 2AZ, UK.
authors.forename: M A
authors.initials: MA
authors.lastname: Accardi
authors.affiliation: Department of Mechanical Engineering, Imperial College London, London SW7 2AZ, UK.
authors.forename: D
authors.initials: D
authors.lastname: Dini
authors.affiliation: Department of Materials, Imperial College London, London, UK; Department of Bioengineering, Imperial College London, London, UK; Institute of Biomedical Engineering, Imperial College London, London, UK. Electronic address: m.stevens@imperial.ac.uk.
authors.forename: M M
authors.initials: MM
authors.lastname: Stevens
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000502:physiology*; D002417:Cattle; D049109:Cell Proliferation; D019902:Chondrocytes / Q000166:cytology / Q000378:metabolism; D019245:Compressive Strength; D004247:DNA / Q000378:metabolism; D020869:Gene Expression Profiling; D006025:Glycosaminoglycans / Q000378:metabolism; D007368:Interferometry; D012995:Solubility; D013718:Tensile Strength; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D006025:Glycosaminoglycans; D004247:DNA
keywords: Cartilage; Regenerative medicine; Repair; Scaffolds; Tissue engineering