Fig. 1

a, dose-dependent effects of MSO on LPS-triggered IL-6 production (s ± SEM). Peritoneal macrophages were treated with three concentrations of MSO one hour prior to the addition of 1 μg/mL LPS, and IL-6 production in the medium was quantitated by ELISA 4 h and 6 h after LPS treatment (n = 6, *p < 0.05). b, effects of MSO on intracellular and extracellular IL-6 production. Cells were treated with 9 mM MSO, and in addition to measuring IL-6 in the medium after LPS treatment, cells were washed, lysed, and the amount of IL-6 in the lysate was quantitated as a measure of intracellular IL-6. Untreated cells, or cells treated with MSO alone (minus-LPS) did not produce detectable levels of IL-6. ELISA values obtained from LPS stimulated control (minus-MSO) samples were normalized as 100%, and the average amounts of IL-6 produced in the treated supernatant and lysate samples are indicated as percentages of the controls. These data represent averages from 3 additional macrophage preps different from those represented in A, with three biological replicates for each treatment. *p < 0.05, **p < 0.01, ***p < 0.001. C, immunofluorescence detection of intracellular IL-6 protein, 6 h after LPS treatment. The top row shows, from left to right, levels of intracellular IL-6 in untreated cells, cells treated with LPS, treated with LPS and MSO, or treated with just MSO. The same cells were also stained with the nuclear stain DAPI, and the two fluorescent images were merged in the bottom row, showing that the nuclei of treated and untreated cells appear the same