Differential Use of Human Neutrophil Fcγ Receptors for Inducing Neutrophil Extracellular Trap Formation

Figure 2

NETs are induced by PMA and FcγRIIIb cross-linking. Human neutrophils (PMN) were left untreated (—) or were stimulated with 20 nM phorbol 12-myristate 13-acetate (PMA), by cross-linking FcγRIIa with mAb IV.3, by cross-linking FcγRIIIb with mAb 3G8, by cross-linking β1 integrins with mAb TS2/16, or by cross-linking β2 integrins with mAb IB4. The relative amount of NETs, as extracellular DNA of nonfixed cells, was estimated from SYTOX Green fluorescence in relative fluorescent units (RFU) at 4 hours after stimulation, as described in Materials and Methods. Data are mean ± SEM of 4 experiments. Asterisks denote conditions that are statistically different from control ().