title: Bilayered silk/silk-nanoCaP scaffolds for osteochondral tissue engineering: In vitro and in vivo assessment of biological performance.
abstract: Novel porous bilayered scaffolds, fully integrating a silk fibroin (SF) layer and a silk-nano calcium phosphate (silk-nanoCaP) layer for osteochondral defect (OCD) regeneration, were developed. Homogeneous porosity distribution was achieved in the scaffolds, with calcium phosphate phase only retained in the silk-nanoCaP layer. The scaffold presented compressive moduli of 0.4MPa in the wet state. Rabbit bone marrow mesenchymal stromal cells (RBMSCs) were cultured on the scaffolds, and good adhesion and proliferation were observed. The silk-nanoCaP layer showed a higher alkaline phosphatase level than the silk layer in osteogenic conditions. Subcutaneous implantation in rabbits demonstrated weak inflammation. In a rabbit knee critical size OCD model, the scaffolds firmly integrated into the host tissue. Histological and immunohistochemical analysis showed that collagen II positive cartilage and glycosaminoglycan regeneration presented in the silk layer, and de novo bone ingrowths and vessel formation were observed in the silk-nanoCaP layer. These bilayered scaffolds can therefore be promising candidates for OCD regeneration.
authors.affiliation: 3B's Research Group-Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, S. Cláudio de Barco, 4806-909 Taipas, Guimarães, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal.
authors.forename: Le-Ping
authors.initials: LP
authors.lastname: Yan
authors.affiliation: 3B's Research Group-Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, S. Cláudio de Barco, 4806-909 Taipas, Guimarães, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Silva-Correia
authors.affiliation: 3B's Research Group-Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, S. Cláudio de Barco, 4806-909 Taipas, Guimarães, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal.
authors.forename: Mariana B
authors.initials: MB
authors.lastname: Oliveira
authors.affiliation: 3B's Research Group-Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, S. Cláudio de Barco, 4806-909 Taipas, Guimarães, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal; Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Portugal; Orthopedic Department, Centro Hospitalar do Alto Ave, Guimarães, Portugal.
authors.forename: Carlos
authors.initials: C
authors.lastname: Vilela
authors.affiliation: 3B's Research Group-Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, S. Cláudio de Barco, 4806-909 Taipas, Guimarães, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal; Saúde Atlântica Sports Center-FC Porto Stadium, Minho University and Porto University Research Center, Porto, Portugal; Orthopedic Department, Centro Hospitalar Póvoa de Varzim, Vila do Conde, Portugal.
authors.forename: Hélder
authors.initials: H
authors.lastname: Pereira
authors.affiliation: 3B's Research Group-Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, S. Cláudio de Barco, 4806-909 Taipas, Guimarães, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal.
authors.forename: Rui A
authors.initials: RA
authors.lastname: Sousa
authors.affiliation: 3B's Research Group-Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, S. Cláudio de Barco, 4806-909 Taipas, Guimarães, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal.
authors.forename: João F
authors.initials: JF
authors.lastname: Mano
authors.affiliation: 3B's Research Group-Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, S. Cláudio de Barco, 4806-909 Taipas, Guimarães, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal; CBQF-Center for Biotechnology and Fine Chemistry, School of Biotechnology, Portuguese Catholic University, Porto 4200-072, Portugal.
authors.forename: Ana L
authors.initials: AL
authors.lastname: Oliveira
authors.affiliation: 3B's Research Group-Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, S. Cláudio de Barco, 4806-909 Taipas, Guimarães, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal. Electronic address: miguel.oliveira@dep.uminho.pt.
authors.forename: Joaquim M
authors.initials: JM
authors.lastname: Oliveira
authors.affiliation: 3B's Research Group-Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, AvePark, S. Cláudio de Barco, 4806-909 Taipas, Guimarães, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal.
authors.forename: Rui L
authors.initials: RL
authors.lastname: Reis
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000502:physiology*; D002130:Calcium Phosphates / Q000737:chemistry*; D002356:Cartilage / Q000502:physiology*; D066298:In Vitro Techniques; D011817:Rabbits; D047011:Silk; D023822:Tissue Engineering; D054457:Tissue Scaffolds; D055114:X-Ray Microtomography
chemical_list: D002130:Calcium Phosphates; D047011:Silk; C020243:calcium phosphate
keywords: Bilayered scaffold; Calcium phosphate; Nanocomposite; Osteochondral regeneration; Silk fibroin