title: Gene expression and cell differentiation in matrix-associated chondrocyte transplantation grafts: a comparative study.
abstract: OBJECTIVE
  Although scaffold composition and architecture are considered to be important parameters for tissue engineering, their influence on gene expression and cell differentiation is rarely investigated in scaffolds used for matrix-associated autologous chondrocyte transplantation (MACT). In this study we have therefore comparatively analyzed the gene expression of important chondrogenic markers in four clinical applied cell-graft systems with very different scaffold characteristics.
  
  
  METHODS
  Residuals (n=165) of four different transplant types (MACI®, Hyalograft®C, CaReS® and Novocart®3D) were collected during surgery and analyzed for Col1, Col2, aggrecan, versican, melanoma inhibitory activity (MIA) and IL-1β by real-time PCR. Scaffold and cell morphology were evaluated by histology and electron microscopy.
  
  
  RESULTS
  Despite the cultivation on 3D scaffolds, the cell differentiation on all transplant types didn't reach the levels of native cartilage. Gene expression highly differed between the transplant types. The highest differentiation of cells (Col2/Col1 ratio) was found in CaReS®, followed by Novocart®3D, Hyalograft®C and MACI®. IL-1β expression also exhibited high differences between the scaffolds showing low expression levels in Novocart®3D and CaReS® and higher expression levels in MACI® and Hyalograft®C.
  
  
  CONCLUSIONS
  Our data indicate that scaffold characteristics as well as culture conditions highly influence gene expression in cartilage transplants and that these parameters may have profound impact on the tissue regeneration after MACT.
authors.affiliation: Medical University of Vienna, Department of Traumatology, Center for Joint and Cartilage, Vienna, Austria. christian.albrecht@meduniwien.ac.at
authors.forename: C
authors.initials: C
authors.lastname: Albrecht
authors.forename: B
authors.initials: B
authors.lastname: Tichy
authors.forename: S
authors.initials: S
authors.lastname: Nürnberger
authors.forename: S
authors.initials: S
authors.lastname: Hosiner
authors.forename: L
authors.initials: L
authors.lastname: Zak
authors.forename: S
authors.initials: S
authors.lastname: Aldrian
authors.forename: S
authors.initials: S
authors.lastname: Marlovits
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D002356:Cartilage / Q000166:cytology*; D002454:Cell Differentiation; D019902:Chondrocytes / Q000378:metabolism* / Q000637:transplantation*; D015870:Gene Expression; D006801:Humans; D008854:Microscopy, Electron; D011506:Proteins / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D015415:Biomarkers; D011506:Proteins