LPS differentially alters surface expression of HLA-DR and accessory molecules in monocytes in a time-dependent manner.

PBMCs were cultured for the first 24 hours with 2 ng/mL or without LPS in the presence of either control murine IgG1, anti-IL-10, or anti-TGF-β MoAb and recultured afterward without further stimulation. Surface molecule expression as assessed by flow cytometry is presented as the ratio of the mean fluorescence intensities (MFI) between cells treated with or without LPS for each of the 3 antibodies. Mean data (± SEM) from 5 independent experiments are shown. Statistical analyses were performed for LPS/IgG1-treated groups by Wilcoxon matched-pairs signed-rank test (*P < .05 versus cultures at 0 hours) or for LPS/neutralizing MoAb-treated groups by Mann- Whitney U test (^#P < .05, ^##P < .01 for LPS/anti-IL-10 MoAb versus LPS/IgG1 MoAb-treated group at the same time point; ⁺P < .05 for LPS/anti-TGF-β MoAb- versus LPS/IgG1 MoAb-treated group at the same time point), respectively.