title: Fibrous Synovium Releases Higher Numbers of Mesenchymal Stem Cells Than Adipose Synovium in a Suspended Synovium Culture Model.
abstract: OBJECTIVE
  To develop an in vitro model, the "suspended synovium culture model," to demonstrate the mobilization of mesenchymal stem cells (MSCs) from the synovium into a noncontacted culture dish through culture medium. In addition, to examine which synovium, fibrous synovium or adipose synovium, released more MSCs in the knee with osteoarthritis.
  
  
  METHODS
  Human synovial tissue was harvested during total knee arthroplasty from knee joints of 34 patients with osteoarthritis (28 patients: only fibrous synovium, 6 patients: fibrous and adipose synovium). One gram of synovium was suspended with a thread in a bottle containing 40 mL of culture medium and a 3.5-cm-diameter culture dish at the bottom. After 7 days, the culture dish in the bottle was examined. For the cells harvested, multipotentiality and surface epitopes were analyzed. The numbers of colonies derived from fibrous synovium and adipose synovium were also compared.
  
  
  RESULTS
  Colonies of spindle-shaped cells were observed in the culture dish in all 28 donors. Colonies numbered 26 on average, and the cells derived from colony-forming cells had multipotentiality for chondrogenesis, adipogenesis, calcification, and surface epitopes similar to MSCs. The number was colonies was significantly higher in fibrous synovium than in adipose synovium (P < .05, n = 6).
  
  
  CONCLUSIONS
  We developed a suspended synovium culture model. Suspended synovium was able to release MSCs into a noncontacted culture dish through medium in a bottle. Fibrous synovium was found to release greater numbers of MSCs than adipose synovium in our culture model. CLINICAL RELEVANCE: This model could be a valuable tool to screen drugs capable of releasing MSCs from the synovium into synovial fluid.
authors.affiliation: Center for Stem Cell and Regenerative Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Katagiri
authors.affiliation: Department of Joint Surgery and Sports Medicine, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Matsukura
authors.affiliation: Department of Joint Surgery and Sports Medicine, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Muneta
authors.affiliation: Center for Stem Cell and Regenerative Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Nobutake
authors.initials: N
authors.lastname: Ozeki
authors.affiliation: Center for Stem Cell and Regenerative Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Mizuno
authors.affiliation: Center for Stem Cell and Regenerative Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Hisako
authors.initials: H
authors.lastname: Katano
authors.affiliation: Center for Stem Cell and Regenerative Medicine, Tokyo Medical and Dental University, Tokyo, Japan. Electronic address: sekiya.arm@tmd.ac.jp.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Sekiya
mesh_terms: D050156:Adipogenesis / Q000502:physiology; D000273:Adipose Tissue / Q000473:pathology*; D000368:Aged; D000369:Aged, 80 and over; D002454:Cell Differentiation; D002478:Cells, Cultured; D020219:Chondrogenesis / Q000502:physiology; D003114:Colony-Forming Units Assay; D003470:Culture Media; D005260:Female; D005355:Fibrosis; D006801:Humans; D007719:Knee Joint / Q000473:pathology; D008297:Male; D059630:Mesenchymal Stem Cells / Q000473:pathology* / Q000502:physiology; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D013583:Synovial Membrane / Q000473:pathology*; D046509:Tissue Culture Techniques
chemical_list: D003470:Culture Media