Uptake of aggregated immunoglobulin by the mouse kidney. I. Effect of endotoxin.

Endotoxin (ET) pretreatment of mice resulted in increased liver and spleen uptake and decreased circulating levels of aggregated IgC (AggIgG) compared to control animals. ET had no effect upon the uptake of AggIgG by lung or whole kidney cortex. However, immunofluorescent microscopy revealed increased localization of AggIgG in the mesangium of ET mice at 1 but not at 2 or 16 h after administration of AggIgG. These studies show that mesangial macromolecular uptake is not solely dependent upon blood levels, but appears to be influenced by unknown and probably complex variables.