title: Correlation Analysis of SOX9, -5, and -6 as well as COL2A1 and Aggrecan Gene Expression of Collagen I Implant-Derived and Osteoarthritic Chondrocytes.
abstract: OBJECTIVE
  Matrix-assisted autologous chondrocyte implantation is frequently applied to replace damaged cartilage in order to support tissue regeneration or repair and to prevent progressive cartilage degradation and osteoarthritis. Its application, however, is limited to primary defects and contraindicated in the case of osteoarthritis that is partially ascribed to dedifferentiation and phenotype alterations of chondrocytes obtainable from patients' biopsies. The differentiation state of chondrocytes is reflected at the level of structural gene (COL2A1, ACAN, COL1A1) and transcription factor (SOX9, 5, 6) expression.
  
  
  METHODS
  We determined the mRNA abundances of COL2A1, ACAN, and COL1A1as well as SOX9, -5, and -6 of freshly isolated and passaged collagen I implant-derived and osteoarthritic chondrocytes via reverse transcription-polymerase chain reaction. Moreover, we analyzed the correlation of structural and transcription factor gene expression. Thus, we were able to evaluate the impact of the mRNA levels of transcription factors on the expression of cartilage-specific structural genes.
  
  
  RESULTS
  Significant differences were obtained (1) for freshly isolated osteoarthritic versus collagen I implant-derived chondrocytes, (2) due to passaging of the respective cell sources, (3) for osteoarthritic versus nonosteoarthritic chondrocytes, and (4) for COL2A1 versus ACAN expression with respect to the coherence with SOX9, -5, and -6 transcript levels.
  
  
  CONCLUSIONS
  Our results might contribute to a better understanding of the transcriptional regulation of structural gene expression of chondrocytes with implications for their use in matrix-assisted autologous chondrocyte implantation.
authors.affiliation: Center for Regenerative Medicine and Orthopaedics, Department for Clinical Medicine and Biotechnology, Danube University Krems, Krems, Austria.
authors.forename: Hannes
authors.initials: H
authors.lastname: Zwickl
authors.affiliation: Center for Regenerative Medicine and Orthopaedics, Department for Clinical Medicine and Biotechnology, Danube University Krems, Krems, Austria.
authors.forename: Eugenia
authors.initials: E
authors.lastname: Niculescu-Morzsa
authors.affiliation: Center for Regenerative Medicine and Orthopaedics, Department for Clinical Medicine and Biotechnology, Danube University Krems, Krems, Austria.
authors.forename: Florian
authors.initials: F
authors.lastname: Halbwirth
authors.affiliation: Center for Regenerative Medicine and Orthopaedics, Department for Clinical Medicine and Biotechnology, Danube University Krems, Krems, Austria.
authors.forename: Christoph
authors.initials: C
authors.lastname: Bauer
authors.affiliation: Center for Regenerative Medicine and Orthopaedics, Department for Clinical Medicine and Biotechnology, Danube University Krems, Krems, Austria.
authors.forename: Vivek
authors.initials: V
authors.lastname: Jeyakumar
authors.affiliation: Center for Regenerative Medicine and Orthopaedics, Department for Clinical Medicine and Biotechnology, Danube University Krems, Krems, Austria.
authors.forename: Angelique
authors.initials: A
authors.lastname: Reutterer
authors.affiliation: Center for Regenerative Medicine and Orthopaedics, Department for Clinical Medicine and Biotechnology, Danube University Krems, Krems, Austria.
authors.forename: Manuela
authors.initials: M
authors.lastname: Berger
authors.affiliation: Center for Regenerative Medicine and Orthopaedics, Department for Clinical Medicine and Biotechnology, Danube University Krems, Krems, Austria.
authors.forename: Stefan
authors.initials: S
authors.lastname: Nehrer
keywords: chondrocytes; collagen; correlation; osteoarthritis; transcription factor