Defect of sinusoidal Fc receptors and immune complex uptake in CCl4-induced liver cirrhosis in rats.

The purpose of this paper is to provide a histopathologic basis for abnormalities in immune-complex clearance in liver disease. Fc receptors in CCl4-induced liver cirrhosis in rats were studied by applying peroxidase-antiperoxidase immunoglobulin G complex as a ligand to the frozen sections. Intravenous injection of bovine serum albumin-antibovine serum albumin complexes or colloidal carbon was combined with histological staining for endogenous peroxidase, fibronectin, laminin, or a lectin, Bandeiraea simplicifolia agglutinin I. In the cirrhotic process, sinusoidal Fc receptors showed a weakened reactivity to the ligand with focal absence, and the length of the Fc receptor-positive portion of the sinusoids in unit area decreased to about 50% of the normal value in the advanced cirrhosis. Fibronectin and the lectin showed the presence of sinusoids where Fc receptors were absent. The endothelium in Fc receptor-negative areas did not take up either immune complexes or carbon, and Kupffer cells were absent in these areas. A disturbed immune-complex metabolism was thus suggested to occur in association with the defect of sinusoidal Fc receptors in liver cirrhosis. These abnormalities appeared to not be directly related to perisinusoidal laminin deposition, i.e., capillarization of the sinusoid.