The identification and characterization of two populations of aggregating proteoglycans of high buoyant density isolated from post-natal human articular cartilages of different ages

Biochem J. 1987 Dec 15;248(3):735-40. doi: 10.1042/bj2480735.


After chromatography on Sepharose CL-2B under associative conditions, high-buoyant-density human articular-cartilage proteoglycans were analysed biochemically and by radioimmunoassay with monoclonal antibodies to a core-protein-related epitope and to keratan sulphate. An examination of proteoglycans from individuals of different ages revealed the presence at 1 year of mainly a single polydisperse population containing chondroitin sulphate (uronic acid) and keratan sulphate. From 4 years onwards a smaller keratan sulphate-rich and chondroitin sulphate-deficient population appears in increasing amounts until 15 years. At the same time the larger population shows a progressive decrease in size from 1 year onward. By 23 years and after the proportion of keratan sulphate in the larger chondroitin sulphate-rich proteoglycan increases. Both adult proteoglycan populations are shown immunologically to aggregate with hyaluronic acid, with the smaller showing a greater degree of interaction. The larger population is richer in serine and glycine, and the smaller population contains more glutamic acid/glutamine, alanine, phenylalanine, lysine and arginine; its protein content is also higher. Whether the larger post-natal population represents a different gene product from the single polydisperse population found in the human fetus, which has a different amino acid composition, remains to be established. The smaller population, which represents approximately one-third the mass of the larger population in the adult, may represent a degradation product of the larger population, in which the hyaluronic acid-binding region and keratan sulphate-rich region are conserved.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aging*
  • Amino Acids / analysis
  • Cartilage, Articular / metabolism*
  • Chromatography, Gel
  • Galactosamine / analysis
  • Glucosamine / analysis
  • Humans
  • Macromolecular Substances
  • Middle Aged
  • Proteoglycans / metabolism*
  • Radioimmunoassay
  • Uronic Acids / analysis


  • Amino Acids
  • Macromolecular Substances
  • Proteoglycans
  • Uronic Acids
  • Galactosamine
  • Glucosamine