Dulbecco’s modified Eagle’s medium (DMEM-glutamax, Gibco), RPMI-1640 (Gibco), fetal bovine serum (FBS), penicillin (100U/ml) and streptomycin (100μg/ml), all from Gibco, Carlsbad, CA; PMA, ionomycin, saponin and A23187 calcium ionophore were from Sigma-Aldrich. Murine PMNs were isolated with Percoll (Sigma) and cultured in RPMI-1640 supplemented with l-glutamine, 2% bovine serum albumin (BSA) (Gibco), and 10 mM HEPES (Gibco). PBS tablets were from Gibco.
For immunofluorescence the following primary antibodies were used: polyclonal anti-neutrophil elastase (anti-NE) Ab (Abcam), polyclonal anti-human myeloperoxidase (anti-MPO) (Dako), anti-citrullinated H3 (Abcam), CF488–labeled anti-rabbit Ab (Biotium), CF555-conjugated goat anti-rabbit IgG (H+L) Ab (Biotium) and DAPI (Sigma).