Figure 2.

IL‐6 regulation by mast cells is mediated by serglycin‐dependent serine proteases. (A and B) Mast cell degranulation was induced by IgE‐receptor crosslinking (IgE/Ag) or by calcium ionophore A23187 (CI). IL‐6 was added to the cell‐free supernatant containing the degranulate in the presence of a serine protease inhibitor (Pefabloc SC; 2 mM final concentration). Medium alone with addition of IL‐6 was used as control. The levels of IL‐6 in supernatants taken after 1 h, 4 h, and 24 h were measured by ELISA. Data were calculated as percent residual IL‐6 compared to control. Data are expressed as means ± SEM. ***P < 0.001 for degranulated WT sample versus degranulated serglycin^−/− sample, and WT sample with inhibitor versus no inhibitor.