Juvenile hyaline fibromatosis: impaired collagen metabolism in human skin fibroblasts

Juvenile hyaline fibromatosis (JHF) is inherited as a fatal autosomal recessive disorder characterised by multiple tumorous mucocutaneous proliferations. In this paper a 14 month old girl with JHF is described. For this condition, a malfunction of collagen synthesis is considered as the pathogenetic cause. Recently published data have revealed an absent band for type III collagen (TIIIC) chain in western blot studies of clinically unaffected JHF skin. Therefore supernatants of skin fibroblast cell cultures, obtained from normal human skin, were analysed for type I collagen (TIC) and TIIIC metabolites by radioimmunoassays. Besides the typical morphological connective tissue changes in the skin lesions, TIC synthesis and degradation were found increased in JHF fibroblasts compared with control fibroblasts. In contrast, TIIIC overall metabolism was significantly reduced by 36% compared with controls.