[Chondrogenesis in vitro by epiphyseal chondrocytes seeding into three-dimensional scaffolds]

To observe the efficiency and biological characteristics in regenerating in vitro tissue-engineered cartilage from epiphyseal chondrocyte-scaffold complex.

The first passage epiphyseal chondrocytes were collected and mixed with the biological gel-matrix, the chondrocyte-gel fluid was dropped into the scaffold to form a complex. The complexes were in vitro cultivated. The changes of complexes in morphology and synthesis of collagens type II and type I and aggrecan were observed under the gross and the inverted and light microscopes. The sulfate GAG content in complexes was measured by the the modified dimethylmethylene blue method.

During cultivation, the complexes could keep its original shape with the stable homogeneous three-dimensional distribution of chondrocytes, gradually became milk white and translucence with their rigidity increasing. In the 1st week, the chondrocytic lacunae formed in the complexes. After 2 weeks, the complex was gradually reorganized into the mature engineered cartilage with rich collagen type II and aggrecan and typical cartilage histological structure, but with negative immunological staining of collagen type I. In the 4th week, the engineered cartilage resembled the nature epiphyseal plate in the characteristic of histological structure, and had over 34% of the sulfate GAG content of the natural epiphyseal plate.

The epiphyseal chondrocyte-scaffold complex can be reorganized into typical cartilage with the epiphyseal-like histological structure, and be fit for repairing the epiphyseal defect. The tissue engineered cartilage cultivated for 1-2 weeks may be a good choice for repairing epiphyseal defect.