Stimulation of proteoglycan synthesis by fibroblastic cells in culture due to the addition of "matrigenin" from bovine bone.

Hyaluronic acid is the major glycosaminoglycan characteristically secreted in culture by human synovial fibroblastic cells, but stimulated proteoglycan synthesis, as well as hyaluronic acid synthesis, was observed when a partially purified factor from bovine bone, containing "matrigenin" activity, was added to these cells. Cultures were labelled with [35S]SO4 and [3H]glucosamine and the radioactive glycoconjugates were extracted from the medium under dissociative conditions. After a preliminary separation of the radioactive high molecular weight compounds, the proteoglycans were separated from hyaluronic acid and glycoproteins by ion-exchange chromatography in 8 M urea. The proteoglycan fraction from the fibroblastic cells, whose synthesis was stimulated by the "matrigenin" activity, contained at least two species, the lower molecular weight proteoglycan eluting in the range of 400-600 K under dissociative conditions during gel filtration chromatography.