HIGH DOSES OF INTRAVENOUS IMMUNOGLOBULIN G ENHANCE KUPFFER CELL PHAGOCYTIC FUNCTION DURING THE LATE PHASE OF SEPSIS AND ENDOTOXEMIA IN RATS

The effect of intravenous immunoglobuln G (ivIG) on the hepatic microvascular inflammatory response during the late phase of sepsis and endotoxemia in rats was studied by using in vivo microscopy. One hour after administration of a clinically relevant dose of ivIG (0.5 g/kg body weight, Sandoglobulin), rats were subjected to polymicrobial sepsis induced by cecal ligation and puncture (CLP) or were injected intravenously with lipopolysaccharide (LPS, 0.1 mg/kg body weight). Twenty-four hours after CLP or LPS, the number of leukocytes adhering to the sinusoidal wall was increased 11.0-fold in CLP-treated animals and 5.6-fold in LPS-treated animals, respectively, compared with the controls. Concomitantly, the numbers of swollen sinusoidal endothelial cells were increased 4.2-fold and 3.2-fold. The number of perfused sinusoids was decreased by 35% and by 24%. These responses were minimized by pretreatment with high doses of ivIG. Kupffer cell phagocytic activity in the periportal sinusoids in CLP-treated animals was decreased by 41%, whereas that in the centrilobular sinusoids in LPS-treated animals was increased by 72%. IvIG significantly elevated this activity in both CLP- and LPS-treated animals and the number of ED2-positive Kupffer cells in tissue sections. The results suggest that ivIG limits the hepatic microvascular inflammatory response during the late phase of sepsis and endotoxemia by affecting Kupffer cell function.