title: Use of cartilage derived from murine induced pluripotent stem cells for osteoarthritis drug screening.
abstract: OBJECTIVE
  The discovery of novel disease-modifying drugs for osteoarthritis (OA) is limited by the lack of adequate genetically defined cartilage tissues for application in high-throughput screening systems. We addressed this need by synthesizing cartilage from induced pluripotent stem cells (iPSCs) to establish and validate an in vitro model of OA.
  
  
  METHODS
  Native or iPSC-derived mouse cartilage samples were treated with the cytokine interleukin-1α (IL-1α) for 3 days to model the inflammatory environment of OA. The biochemical content, mechanical properties, and gene expression of the resulting tissues were assayed. In addition, the inflammatory and catabolic environment of the media was assessed. To establish high-throughput capability, we used a 96-well plate format and conducted a screen of previously identified candidate OA drugs. Glycosaminoglycan (GAG) release into the medium was used as the primary output for screening.
  
  
  RESULTS
  Treatment of iPSC-derived or native cartilage with IL-1α induced characteristic features of OA in a rapid and dose-dependent manner. In addition to the loss of GAGs and tissue mechanical properties, IL-1α treatment induced the expression of matrix metalloproteinases and increased the production of the inflammatory mediators nitric oxide and prostaglandin E2 . In the high-throughput screen validation, all candidate OA therapeutic agents provided some benefit, but only the NF-κB inhibitor SC514 effectively reduced cartilage loss in response to IL-1α.
  
  
  CONCLUSIONS
  This work demonstrates the utility of iPSCs for studying cartilage pathology and provides a platform for identifying novel, patient-specific therapeutic agents that prevent cartilage degradation and modify the course of OA development.
authors.affiliation: Duke University Medical Center, Durham, North Carolina.
authors.forename: Vincent P
authors.initials: VP
authors.lastname: Willard
authors.forename: Brian O
authors.initials: BO
authors.lastname: Diekman
authors.forename: Johannah
authors.initials: J
authors.lastname: Sanchez-Adams
authors.forename: Nicolas
authors.initials: N
authors.lastname: Christoforou
authors.forename: Kam W
authors.initials: KW
authors.lastname: Leong
authors.forename: Farshid
authors.initials: F
authors.lastname: Guilak
mesh_terms: D000818:Animals; D018501:Antirheumatic Agents / Q000627:therapeutic use; D002356:Cartilage / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D002454:Cell Differentiation; D002478:Cells, Cultured; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D005786:Gene Expression Regulation / Q000187:drug effects; D006025:Glycosaminoglycans / Q000378:metabolism; D057166:High-Throughput Screening Assays / Q000379:methods; D066298:In Vitro Techniques; D053582:Interleukin-1alpha / Q000009:adverse effects / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D010003:Osteoarthritis / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology*; D039904:Pluripotent Stem Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*
chemical_list: D018501:Antirheumatic Agents; D006025:Glycosaminoglycans; D053582:Interleukin-1alpha