Cross-Talk between TLR4 and FcγReceptorIII (CD16) Pathways
Figure 2
In vitro cytokine responses of elicited peritoneal PMNs and macrophages to LPS and IgGIC.
In vitro cytokine responses of elicited peritoneal PMNs (A–D) and macrophages (E,F). Cells (3×106 cells/ml) from either Wt or TLR4 mut mice were incubated for 4 hr with LPS (20 ng/ml) or IgGIC; 100 µg/ml), respectively. In addition, macrophages were incubated with polymyxin-treated BSA IgG immune complexes (p.-t. BSA IC, 100 µg/ml) or peroxidase/anti-peroxidase IgGIC immune complexes (PAP IC, 100 µg/ml). (A) IL-6 release from PMNs after LPS stimulation. (B) TNFα levels after incubation of PMNs with LPS. (C) Concentration of IL-6 in supernatants when PMNs were exposed to IgGIC. (D) Production of TNFα by PMNs and macrophages in the presence of IgGIC. Ctrl = control levels of non-stimulated cells. (E) Release of IL-6 by macrophages into supernatant fluids after stimulation with LPS, IgGIC, p.-t. BSA IC, or PAP IC. (F) TNFα production by macrophages exposed to LPS, IgGIC, p.-t. BSA IC, or PAP IC. The experiments were performed in triplicates for each condition (each bar) with n≥3 donors of cells for each mouse strain, Wt or TLR4 mut. Differences between controls and stimulated cells were—if not otherwise noted—statistically significant (p<0.05).