Phagocytosis, an unrecognized property of murine endothelial liver cells

Impairment of the phagocytic capacities of Kupffer cells, as is found in Frog Virus 3 hepatitis of mice, allows the endothelial liver cells to take up intravenously inoculated latex particles of 1.0 micron diameter. In vitro experiments with cultivated endothelial cells isolated by collagenase perfusion of the liver and purified by centrifugal elutriation demonstrate that uptake occurs via a typical mechanism of phagocytosis involving pseudopodia. Ingestion of latex is inhibited by incubation of the cells at 4 degrees C and by treatment with cytochalasin B, whereas colchicine has no effect. These results demonstrate that: the Kupffer cells are not the only cells of the hepatic sinusoid capable of phagocytosis; and under conditions where the phagocytosis in Kupffer cells is impaired, the endothelial cells may participate in the clearance of large particles from the blood.