Ultrastructural and histochemical analysis of thready material in Pseudoxanthoma elasticum

The components of the thready material in skin lesions of pseudoxanthoma elasticum, recessive Type I, were analysed. Immunoelectron microscopic observation revealed the presence of fibrinogen in the thready material. Part of the fine fibrils in the thready material was sensitive to collagenase. The thready material was also stained by ruthenium red. These results suggest that the thready material is composed at least of fibrinogen, collagenous protein and glycoprotein.