PROTEOGLYCAN SYNTHESIS BY CULTURED HUMAN CHONDROCYTES

Iliac crest biopsies are important in the detection of human skeletal dysplasias. Therefore, culture of these cells may serve as a valuable method for studying proteoglycan metabolism in chondrocytes of individ uals with skeletal abnormalities. Morphological and biochemical studie s were performed on human iliac crest chondrocytes grown in monolayer and in agarose gels. Two proteoglycan populations of different hydrody namic size and glycosaminoglycan composition were synthesized by cells grown in monolayer. Chondrocytes cultured in an agarose gel for 2 wee ks synthesized proteoglycans identical to those of the native tissue w ith respect to hydrodynamic size and glycosaminoglycan chain length. H owever, the ratio of chondroitin-6-sulfate to chondroitin-4-sulfate wa s higher than in the native tissue. This ratio was not influenced by d ifferent sulfate concentrations in the medium. Moreover, treatment wit h ascorbic acid did not influence proteoglycan synthesis; however, the re was a pericellular accumulation of proteoglycans. (C) 1994 Wiley-Li ss, Inc.