[Characteristics of the extracellular matrix in the formation of sclerosis of the chorionic villi (immunofluorescence studies)].

Distribution of the eight components of extracellular matrix in small villi of human placenta was studied with indirect immunofluorescence. Normal full-term pregnancy was found to present rough fibers and type I collagen conglomerates accumulated in the stromal center, while type III and V collagens occurred all over the villous surface. Stromal localization of type IV collagen was recorded as well as its presence in basal membranes of the epithelium and vessels. Fibronectin showed diffuse distribution concentrating along the vessels. Laminin, entactin and in lesser degree heparan sulphate proteoglycan were registered in epithelial and vascular basal membranes. Isolated sclerosis of the villi in pathological pregnancy involved stromal accumulation of type I, III collagens, small fragments of collagens type IV, V and fibronectin. Multiple sclerosis of adherent villi demonstrated hyalin-like conglomerates of various collagens and fibronectin filling up the stroma. Laminin, heparan sulphate proteoglycan and entactin were not observed at these sites.