Neutrophil extracellular traps were quantified by SytoxGreen fluorimetry (20, 40). Neutrophils (2.5 × 104) freshly isolated were cultured in the presence of 0.2 µM SytoxGreen (Invitrogen, Life Technologies) in a 96-well dark microtiter plate at 37°C under 5% CO2 and left untreated or stimulated with the indicated agents over 3 h. PMA was used as the positive control. Fluorescence (excitation 485 nm, emission 535 nm) was measured in a Biotek Synergy H1 Hybrid Reader (Biotek) and results given as mean DNA fluorescence intensity. Photomicrographs in bright field and green fluorescence spectra were assessed with an Olympus IX50 inverted fluorescence microscope coupled to an Olympus XM10 monochromatic CCD camera and analyzed with the Olympus CellSens Dimension software (Olympus).