Lichen myxedematosus serum stimulates human skin fibroblast proliferation.

Serum from patients with lichen myxedematosus, when added to exponentially growing normal human skin fibroblasts, stimulates DNA synthesis and cell proliferation. The degree of response in vitro is correlated with the extent of the disease in vivo and is specific for fibroblasts. The results suggest that there is a systemic factor (or factors) which may play a role in the etiology of diseases affecting the connective tissue.