Fig. 7. Effects of pretreatment of neutrophil membranes and DC membranes by ß-OG on the elicited NADPH oxidase activity in cell-free system. Murine DC membranes (21 µg protein) and bovine neutrophil membranes (6 µg protein) were pretreated by 1% ß-OG for 3 minutes at 0°C. This was followed by the addition of bovine neutrophil cytosol, GTPS, ATP, KCN, MgSO₄ and increasing amounts of arachidonic acid (AA) to activate the NADPH oxidase. The elicited oxidase activity was determined by the production of O₂^– (see Materials and Methods) and expressed in terms of heme b turnover. (A) neutrophil membranes, control (), pretreated by ß-OG (). (B) DC membranes, control (), pretreated by ß-OG ().