title: Establishment of a bipotent cell line CL-1 which differentiates into chondrocytes and adipocytes from adult mouse.
abstract: OBJECTIVE
  Establishment of a clonal bipotent chondroprogenitor cell line from adult mouse to provide a new tool for the elucidation of chondrogenesis in adult animal.
  
  
  METHODS
  A clonal cell line CL-1 was established from tibia of adult mouse. Differentiation of CL-1 was characterized in monolayer culture. Effects of growth factors (TGF-beta(1), IGF-I, bFGF) and hormones (all trans retinoic acid, 1 alpha.25(OH)(2)D(3), PTH (1-34)) on the growth and differentiation of CL-1 were examined. Bipotency of CL-1 in vivo was examined by transplantation into SCID mice.
  
  
  RESULTS
  CL-1 formed alcian blue (pH1.0) positive nodules spontaneously. The nodules were mineralized in the presence of ascorbic acid and beta-glycerophosphate. CL-1 differentiated also into oil red O positive adipocytes spontaneously. CL-1 cells expressed specific genes of chondrocytes (collagen type II, X, aggrecan) and adipocytes (PPAR-gamma(2), aP(2)). Hyaline cartilage and adipose tissue formation was observed also in subcutaneously transplanted CL-1 cells into SCID mice. These data demonstrate that CL-1 has bipotency either in vitro or in vivo. TGF-beta(1)suppressed growth of CL-1 and induced dominant chondrogenesis accompanied with marked suppression of adipogenesis in 10% FCS. IGF-I stimulated both growth (in 3% FCS) and differentiation of CL-1 into both lineages (in 10% FCS). 1 alpha.25(OH)(2)D(3)and all trans retinoic acid acted as negative regulators on proliferation and differentiation of CL-1 in 10% FCS.
  
  
  CONCLUSIONS
  CL-1 will be a useful tool for the understanding of chondrogenesis in adult animal. Furthermore, CL-1 can be also a powerful tool for screening of the chondrogenic agent.
authors.affiliation: Fuji-Gotemba research laboratories, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka, 412-8513, Japan. kitamurahdt@chugai-pharm.ac.jp
authors.forename: Hidetomo
authors.initials: H
authors.lastname: Kitamura
mesh_terms: D017667:Adipocytes / Q000502:physiology*; D000423:Alcian Blue; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D017690:Cell Transplantation / Q000379:methods; D019902:Chondrocytes / Q000502:physiology*; D002999:Clone Cells / Q000502:physiology; D004396:Coloring Agents; D005260:Female; D007150:Immunohistochemistry / Q000379:methods; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D008854:Microscopy, Electron / Q000379:methods; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013234:Stem Cells / Q000502:physiology; D016212:Transforming Growth Factor beta / Q000494:pharmacology
chemical_list: D004396:Coloring Agents; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; D007334:Insulin-Like Growth Factor I; D000423:Alcian Blue