Electron microscopic investigation on Ito cells and Disse's space in patients with extrahepatic cholestasis. Immunohistochemistry of collagen type IV and fibronectin in hepatic sinusoids.
Extrahepatic cholestasis is one of the main factors causing liver fibrosis. Surgical biopsies of six patents were studied: one with normal liver (control patient), and five with different degrees of extrahepatal cholestasis with hepatocellular degenerative and necrotic changes. Monospecific antibodies directed against type IV collagen and fibronectin were localized by light microscopical immunohistochemistry. Type IV collagen was found in all basement membranes: ductal, vascular, neural, Intensive, almost continuous deposits of it were found along the entire length of the sinusoid. Fibronectin, the structural glycoprotein, was codistributed with type IV collagen in portal matrix and in perisinusoidal location. It did not decorate the basement membranes of bile ducts and stained more intensely than type IV collagen at the border between portal stroma and parenchyma. The intensity of the two antibodies increased corresponding with the heaviness of parenchymal deterioration. There was weaker staining behavior of the extracellular matrix regarding collagen IV and fibronectin in the area of heavy bilirubin impregnation. The sinusoid morphology in the regions with fibrosis and increased extracellular matrix formation in periportal areas was reported. Disses's space was distended and occupied by collagen bundles, amorphous matrix, swollen hepatocyte microvilli, and basement membrane-like material. Ito cells transformed into transitional cells or myofibroblast-like cells. Sinusoidal changes and increased collagen IV as well as perisinusoidal fibronectin formation coincided with the aggravation of cholestasis.
Gulubova
M
M
Department of Pathology, Medical Institute, Sofia, Bulgaria.
Popov
A
A
D001706:Biopsy; D002452:Cell Count; D001651:Cholestasis, Extrahepatic / Q000097:blood / Q000378:metabolism* / Q000473:pathology*; D003094:Collagen / Q000032:analysis*; D005353:Fibronectins / Q000032:analysis*; D006801:Humans; D007124:Immunoenzyme Techniques; D008099:Liver / Q000737:chemistry* / Q000473:pathology* / Q000648:ultrastructure; D008854:Microscopy, Electron; D008871:Microvilli / Q000648:ultrastructure
D005353:Fibronectins; D003094:Collagen