Changes in the secretion and glycosylation of fibronectin by human skin fibroblasts associated with tuberous sclerosis

Fibroblasts from skin and skin lesions of patients with tuberous sclerosis (TS) and from skin of normal individuals were grown in culture. ELISA showed that the spent medium of those derived from TS skin lesions contained significantly more fibronectin (FN) than spent medium from the other cells. Amino acid compositional analysis of the FN from TS and normal sources revealed no substantial differences. However the FN of fibroblasts from TS-skin lesions was shown by HPAEC to contain a two- to three-fold increased content of carbohydrate. The changed monosaccharide composition was consistent with an increased content of N- and O-linked glycans and with the former containing polylactosamine chains. Fibroblasts from a normal individual were shown to proliferate more slowly and to produce larger cells when grown on FN from a TS skin lesion compared to growth on FN from normal skin.