title: Three-dimensional assembly of tissue-engineered cartilage constructs results in cartilaginous tissue formation without retainment of zonal characteristics.
abstract: Articular cartilage has limited regenerative capabilities. Chondrocytes from different layers of cartilage have specific properties, and regenerative approaches using zonal chondrocytes may yield better replication of the architecture of native cartilage than when using a single cell population. To obtain high seeding efficiency while still mimicking zonal architecture, cell pellets of expanded deep zone and superficial zone equine chondrocytes were seeded and cultured in two layers on poly(ethylene glycol)-terephthalate-poly(butylene terephthalate) (PEGT-PBT) scaffolds. Scaffolds seeded with cell pellets consisting of a 1:1 mixture of both cell sources served as controls. Parallel to this, pellets of superficial or deep zone chondrocytes, and combinations of the two cell populations, were cultured without the scaffold. Pellet cultures of zonal chondrocytes in scaffolds resulted in a high seeding efficiency and abundant cartilaginous tissue formation, containing collagen type II and glycosaminoglycans (GAGs) in all groups, irrespective of the donor (n = 3), zonal population or stratified scaffold-seeding approach used. However, whereas total GAG production was similar, the constructs retained significantly more GAG compared to pellet cultures, in which a high percentage of the produced GAGs were secreted into the culture medium. Immunohistochemistry for zonal markers did not show any differences between the conditions. We conclude that spatially defined pellet culture in 3D scaffolds is associated with high seeding efficiency and supports cartilaginous tissue formation, but did not result in the maintenance or restoration of the original zonal phenotype. The use of pellet-assembled constructs leads to a better retainment of newly produced GAGs than the use of pellet cultures alone.
authors.affiliation: Department of Orthopaedics, University Medical Centre Utrecht, The Netherlands.|Department of Equine Sciences, Faculty of Veterinary Sciences, Utrecht University, The Netherlands.
authors.forename: W
authors.initials: W
authors.lastname: Schuurman
authors.affiliation: Department of Orthopaedics, University Medical Centre Utrecht, The Netherlands.
authors.forename: E B
authors.initials: EB
authors.lastname: Harimulyo
authors.affiliation: Department of Orthopaedics, University Medical Centre Utrecht, The Netherlands.
authors.forename: D
authors.initials: D
authors.lastname: Gawlitta
authors.affiliation: Department of Orthopaedic Surgery, University of Otago, Christchurch, New Zealand.
authors.forename: T B F
authors.initials: TB
authors.lastname: Woodfield
authors.affiliation: Department of Orthopaedics, University Medical Centre Utrecht, The Netherlands.|Faculty of Veterinary Sciences, University of Utrecht, The Netherlands.
authors.forename: W J A
authors.initials: WJ
authors.lastname: Dhert
authors.affiliation: Department of Equine Sciences, Faculty of Veterinary Sciences, Utrecht University, The Netherlands.
authors.forename: P R
authors.initials: PR
authors.lastname: van Weeren
authors.affiliation: Department of Orthopaedics, University Medical Centre Utrecht, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Malda
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002358:Cartilage, Articular / Q000502:physiology*; D002478:Cells, Cultured; D024042:Collagen Type I / Q000378:metabolism; D024043:Collagen Type II / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D006025:Glycosaminoglycans / Q000378:metabolism; D006736:Horses; D006801:Humans; D007150:Immunohistochemistry; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; D024043:Collagen Type II; D006025:Glycosaminoglycans; D004247:DNA
keywords: 3D; cartilage; chondrocytes; fibre deposition; regenerative medicine; scaffolds; tissue engineering; zonal