Scleromyxedema serum increases proliferation but not the glycosaminoglycan synthesis of dermal fibroblasts.

In comparison to normal fibroblasts cultured in parallel, scleromyxedema fibroblasts grew less well, synthesized increased amounts of glycosaminoglycans (GAG) in vitro and had ultrastructural abnormalities. Serum obtained from a patient with scleromyxedema increased in vitro fibroblast proliferation but not the GAG synthesis per cell. Serum obtained after therapy, at the time when clinical improvement was observed, continued to stimulate fibroblast proliferation. Thus the serum factor stimulating the fibroblast proliferation did not modulate their GAG synthesis and had no direct relationship to disease activity.