Glycosaminoglycans of cultured human fetal uveal melanocytes and comparison with those produced by cultured human melanoma cells

Abstract

The glycosaminoglycans produced by human fetal uveal melanocytes and by human melanoma cells were examined. The cells were grown in the presence of [3H]glucosamine and [35S]sulfate, and the labeled glycosaminoglycans were isolated from the cells, spent medium and intracellular material. The distribution of the glycosaminoglycans was similar in cells and spent media, which together accounted for 95% of the total. Of the total 3H-labeled glycosaminoglycans produced by the melanocyte culture, 42% was in chondroitin 4-sulfate, 25% in heparan sulfate, 16% in chondroitin 6-sulfate and 17% in hyaluronic acid. HM7 human melanoma cultures produced no chondroitin 6-sulfate, increased quantities of heparan sulfate and less hyaluronic acid. A heparan sulfate fraction obtained from melanocytes required heparitinase and heparinase for complete degradation, indicating the presence of heparin-like molecules in this fraction. The corresponding fraction from melanoma cells was totally degraded by heparitinase alone.