title: Acid ceramidase treatment enhances the outcome of autologous chondrocyte implantation in a rat osteochondral defect model.
abstract: OBJECTIVE
  The overall aim of this study was to evaluate how supplementation of chondrocyte media with recombinant acid ceramidase (rhAC) influenced cartilage repair in a rat osteochondral defect model.
  
  
  METHODS
  Primary chondrocytes were grown as monolayers in polystyrene culture dishes with and without rhAC (added once at the time of cell plating) for 7 days, and then seeded onto Bio-Gide® collagen scaffolds and grown for an additional 3 days. The scaffolds were then introduced into osteochondral defects created in Sprague-Dawley rat trochlea by a microdrilling procedure. Analysis was performed 6 weeks post-surgery macroscopically, by micro-CT, histologically, and by immunohistochemistry.
  
  
  RESULTS
  Treatment with rhAC led to increased cell numbers and glycosaminoglycan (GAG) production (∼2 and 3-fold, respectively) following 7 days of expansion in vitro. Gene expression of collagen 2, aggrecan and Sox-9 also was significantly elevated. After seeding onto Bio-Gide®, more rhAC treated cells were evident within 4 h. At 6 weeks post-surgery, defects containing rhAC-treated cells exhibited more soft tissue formation at the articular surface, as evidenced by microCT, as well as histological evidence of enhanced cartilage repair. Notably, collagen 2 immunostaining revealed greater surface expression in animals receiving rhAC treated cells as well. Collagen 10 staining was not enhanced.
  
  
  CONCLUSIONS
  The results further demonstrate the positive effects of rhAC treatment on chondrocyte growth and phenotype in vitro, and reveal for the first time the in vivo effects of the treated cells on cartilage repair.
authors.affiliation: Department of Genetics and Genomic Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
authors.forename: M E
authors.initials: ME
authors.lastname: Frohbergh
authors.affiliation: Institute for the Study of Inborn Errors of Metabolism, Pontificia Universidad Javeriana, Bogota, Colombia.
authors.forename: J M
authors.initials: JM
authors.lastname: Guevara
authors.affiliation: Department of Orthopedic Surgery, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
authors.forename: R P
authors.initials: RP
authors.lastname: Grelsamer
authors.affiliation: Department of Anatomy and Cell Biology, Temple University, Philadelphia, PA, USA.
authors.forename: M F
authors.initials: MF
authors.lastname: Barbe
authors.affiliation: Department of Genetics and Genomic Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
authors.forename: X
authors.initials: X
authors.lastname: He
authors.affiliation: Department of Genetics and Genomic Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Simonaro
authors.affiliation: Department of Genetics and Genomic Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA. Electronic address: Edward.schuchman@mssm.edu.
authors.forename: E H
authors.initials: EH
authors.lastname: Schuchman
mesh_terms: D055573:Acid Ceramidase / Q000494:pharmacology*; D000818:Animals; D002358:Cartilage, Articular / Q000293:injuries* / Q000473:pathology / Q000502:physiology; D002452:Cell Count; D002478:Cells, Cultured; D019902:Chondrocytes / Q000187:drug effects* / Q000378:metabolism / Q000637:transplantation*; D017077:Culture Media, Conditioned; D004353:Drug Evaluation, Preclinical / Q000379:methods; D005260:Female; D006025:Glycosaminoglycans / Q000096:biosynthesis; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000494:pharmacology; D012038:Regeneration / Q000187:drug effects; D054457:Tissue Scaffolds; D014945:Wound Healing / Q000187:drug effects; D055114:X-Ray Microtomography
chemical_list: D017077:Culture Media, Conditioned; D006025:Glycosaminoglycans; D011994:Recombinant Proteins; D055573:Acid Ceramidase
keywords: Acid ceramidase; Autologous chondrocyte implantation (ACI); Cartilage tissue engineering; In vivo; Osteochondral defect model; Primary chondrocyte expansion