title: [Study of inducing bone marrow-derived mesenchymal stem cells into chondrocytes in vitro].
abstract: OBJECTIVE
  To explore a method of isolation, culture and chondrogenic phenotype differentiation of mesenchymal stem cell (MSCs) from the bone marrow of rats in vitro and to offer experimental reference for the resources of seeding cells in cartilage tissue engineering.
  
  
  METHODS
  MSCs were isolated from bone marrow and purified by density gradient centrifuge and cultured in vitro. The MSC adherence formed and those in passage 3 were chosen to induce into chondrogenic differentiation. After 7, 14, 21 days, immunohistochemical techique was applied to detect the expression of collagen type II. The differentiated cells were implanted on the CPP/PLLA composites. After the cell-scaffold complex was cultured in vitro for one week, the ultrastructure of the scaffold was observed with scanning electron microscopy.
  
  
  RESULTS
  The differentiated cells changed from a spindle-like fibroblastic appearance to a polygonal shape, the capability of proliferation was down markedly. Immunohistochemical staining of collagen II were positive for the pass age, especially in the 21st days. Induced MSCs were well adherent to the scaffold composites and the cells were embedded by the cell-matrix.
  
  
  CONCLUSIONS
  Under the induced medium, MSCs can differentiate into chondrogenic phenotype and secrete specificity matrix of cartilage in vitro. MSCs can likely be served as optimal cell source for cartilage tissue engineering.
authors.affiliation: Department of Orthopaedics, Xi'an Red Cross Society Hospital, Xián 710054, Shaanxi, China. zhichaotong@126.com
authors.forename: Zhi-Chao
authors.initials: ZC
authors.lastname: Tong
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yang
authors.forename: Zhi-Qin
authors.initials: ZQ
authors.lastname: Tong
authors.forename: Kun-Zheng
authors.initials: KZ
authors.lastname: Wang
authors.forename: Tuan-Min
authors.initials: TM
authors.lastname: Yang
authors.forename: Zong-Li
authors.initials: ZL
authors.lastname: Shi
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
authors.forename: Xiong
authors.initials: X
authors.lastname: Guo
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology / Q000502:physiology*; D002454:Cell Differentiation; D002469:Cell Separation; D019902:Chondrocytes / Q000166:cytology* / Q000502:physiology; D020219:Chondrogenesis; D005260:Female; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000502:physiology*; D011817:Rabbits; D023822:Tissue Engineering; D054457:Tissue Scaffolds