Abstract
Human neutrophils were incubated either with purified cell envelope lipopolysaccharides (LPS) of salmonella or with different concentrations of LPS combined with Intralipid®. Incubation of neutrophils with LPS alone increased their oxidative metabolism with increased release of oxygen radicals as measured by the nitroblue tetrazolium (NBT) test and chemiluminescence response. The amount of lysozyme released by the cells also increased during incubation with LPS. However, when the neutrophils were incubated with LPS together with Intralipid, the LPS induced stimulation of the neutrophil NBT reduction, chemiluminescence and lysozyme release was significantly decreased. Intralipid might substitute for plasma high density lipoproteins (HDL), which are known to inhibit the LPS effects on the neutrophils in the acute stage of an infection with Gram-negative bacteria.