Type X collagen synthesis in human osteoarthritic cartilage. Indication of chondrocyte hypertrophy

Arthritis Rheum. 1992 Jul;35(7):806-11. doi: 10.1002/art.1780350715.


Objective: To investigate the appearance of hypertrophic chondrocytes in osteoarthritic (OA) cartilage, using type X collagen as a specific marker.

Methods: The biosynthesis of type X collagen was examined by metabolic labeling of freshly isolated articular chondrocytes with 3H-proline, immunoprecipitation, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the synthesized collagens. Extracellular deposition of types X and II collagen was analyzed immunohistochemically.

Results: Immunostaining revealed an irregular distribution of type X collagen, which was localized around chondrocyte clusters in fibrillated OA cartilage, but was absent from the noncalcified region of normal articular cartilage. Freshly isolated OA chondrocytes synthesized predominantly type X collagen, while control chondrocytes synthesized mostly type II collagen.

Conclusion: Our findings indicate focal premature chondrocyte differentiation to hypertrophic cells in OA cartilage.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Cartilage, Articular / chemistry
  • Cartilage, Articular / metabolism*
  • Cartilage, Articular / pathology*
  • Cells, Cultured
  • Collagen / biosynthesis*
  • Collagen / chemistry
  • Female
  • Humans
  • Hypertrophy
  • Immunohistochemistry
  • Male
  • Middle Aged
  • Osteoarthritis / metabolism*
  • Reference Values


  • Collagen