title: Enhanced cell-induced articular cartilage regeneration by chondrons; the influence of joint damage and harvest site.
abstract: OBJECTIVE
  Interactions between chondrocytes and their native pericellular matrix provide optimal circumstances for regeneration of cartilage. However, cartilage diseases such as osteoarthritis change the pericellular matrix, causing doubt to them as a cell source for autologous cell therapy.
  
  
  METHODS
  Chondrons and chondrocytes were isolated from stifle joints of goats in which cartilage damage was surgically induced in the right knee. After 4 weeks of regeneration culture, DNA content and proteoglycan and collagen content and release were determined.
  
  
  RESULTS
  The cartilage regenerated by chondrons isolated from the damaged joint contained less proteoglycans and collagen compared to chondrons from the same harvest site in the nonoperated knee (P < 0.01). Besides, chondrons still reflected whether they were isolated from a damaged joint, even if they where isolated from the opposing or adjacent condyle. Although chondrocytes did not reflect this diseased status of the joint, chondrons always outperformed chondrocytes, even when isolated from the damaged joints (P < 0.0001). Besides increased cartilage production, the chondrons showed less collagenase activity compared to the chondrocytes.
  
  
  CONCLUSIONS
  Chondrons still outperform chondrocytes when they were isolated from a damaged joint and they might be a superior cell source for articular cartilage repair and cell-induced cartilage formation.
authors.affiliation: Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: l.a.vonk@umcutrecht.nl.
authors.forename: L A
authors.initials: LA
authors.lastname: Vonk
authors.affiliation: Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: T S
authors.initials: TS
authors.lastname: de Windt
authors.affiliation: Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: A H M
authors.initials: AH
authors.lastname: Kragten
authors.affiliation: Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Beekhuizen
authors.affiliation: Department of Rheumatology & Clinical Immunology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: S C
authors.initials: SC
authors.lastname: Mastbergen
authors.affiliation: Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands; Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: W J A
authors.initials: WJ
authors.lastname: Dhert
authors.affiliation: Department of Rheumatology & Clinical Immunology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: F P J G
authors.initials: FP
authors.lastname: Lafeber
authors.affiliation: Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: L B
authors.initials: LB
authors.lastname: Creemers
authors.affiliation: Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands; Tissue Regeneration, MIRA Institute, University Twente, Enschede, The Netherlands.
authors.forename: D B F
authors.initials: DB
authors.lastname: Saris
mesh_terms: D000818:Animals; D001861:Bone Regeneration; D002358:Cartilage, Articular / Q000502:physiology*; D064987:Cell- and Tissue-Based Therapy / Q000379:methods*; D002478:Cells, Cultured; D019902:Chondrocytes / Q000637:transplantation*; D004195:Disease Models, Animal; D005260:Female; D006041:Goats; D007719:Knee Joint / Q000473:pathology*; D020370:Osteoarthritis, Knee / Q000473:pathology* / Q000628:therapy
keywords: Autologous chondrocyte implantation; Cartilage repair; Cell therapy; Chondrocytes; Chondrons