title: Polyethylene terephthalate (PET) enhances chondrogenic differentiation of ovine meniscocytes in a hyaluronic acid/polycaprolactone scaffold in vitro.
abstract: OBJECTIVE
  The purpose of this study was to assess the effect of polyethylene terephthalate (PET) on proliferation, differentiation, and attachment of ovine meniscocytes seeded in a hyaluronic acid/polycaprolactone biomaterial (BF-1)
  
  
  METHODS
  BF-1 (30 % hyaluronic acid and 70 % polycaprolactone) cylinders with PET (CO-PET) or without PET, were seeded with 2 x 10(6) ovine meniscus cells. The specimens were harvested in triplets at 12 hours, seven, 14, 21 and 28 days. DNA content was measured to test proliferation, histological analysis for cell morphology, and biochemical assessment of glycosaminoglycan content and RT-PCR for type I and II collagen were used to assess differentiation, with immunohistochemistry as post-translational control. Attachment was evaluated by electronic microscopy at 28 days.
  
  
  RESULTS
  DNA content was consistent and equal across groups, suggesting no effect of PET on cell proliferation. However, the BF-1 CO-PET showed a higher percentage of cells with spherical morphology which is typical for a chondrocytic phenotype. This biomaterial with PET also showed a higher type II collagen mRNA expression and an eightfold higher GAG-content than the material without PET. Small amounts of type I collagen mRNA expression were present on both materials at all time points. PCR results were confirmed by immunohistochemistry.
  
  
  CONCLUSIONS
  Addition of PET to a hyaluronic acid/polycaprolactone biomaterial enhances a cartilaginous phenotype, increased type II collagen mRNA expression and a higher GAG production in ovine mensicocytes.
authors.affiliation: Department of Orthopaedics, Medical University of Vienna, Waehringer Gürtel 18-20, 1090 Vienna, Austria. Ulrich.Koller@meduniwien.ac.at
authors.forename: Ulrich
authors.initials: U
authors.lastname: Koller
authors.forename: Stefan
authors.initials: S
authors.lastname: Nehrer
authors.forename: Patrick
authors.initials: P
authors.lastname: Vavken
authors.forename: Barbara
authors.initials: B
authors.lastname: Kapeller
authors.forename: Reinhard
authors.initials: R
authors.lastname: Windhager
authors.forename: Catharina
authors.initials: C
authors.lastname: Chiari
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D002448:Cell Adhesion / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D019902:Chondrocytes / Q000166:cytology* / Q000187:drug effects; D005260:Female; D006820:Hyaluronic Acid / Q000737:chemistry; D008592:Menisci, Tibial / Q000166:cytology* / Q000187:drug effects; D011091:Polyesters / Q000737:chemistry; D011093:Polyethylene Terephthalates / Q000737:chemistry / Q000494:pharmacology*; D012756:Sheep; D013264:Stifle; D023822:Tissue Engineering; D054457:Tissue Scaffolds / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D011091:Polyesters; D011093:Polyethylene Terephthalates; C016240:polycaprolactone; D006820:Hyaluronic Acid