Abstract
Summary Although injected endotoxin is apparently taken up almost exclusively by the RES and death occurs after failure of the RES to remove circulating endotoxin, protection to lethal doses cannot be obtained by increasing the phagocytic activity alone. Pre-treatment with glucan, which results in a marked proliferation of the RE cells, enhances the phagocytic capacity significantly, but at the same time increases the susceptibility to endotoxin. This unequal increase in phagocytie and detoxifying capacity of the hyperplastic RE cells may be ascribed to an increased permeability of their lysosomes. Stimulation of the RES with restim increases phagocytic capacity to a similar extent, but does not result in proliferation of the RE cells. The observed protective effect of restim against endotoxin may be due to increased detoxifying mechanisms in the presence of normal or stabilized lysosomes within the hyper functional RE cells.