Human neutrophils were obtained by means of dextran sedimentation and Ficoll centrifugation.
Measurements of superoxide anion generation and elastase release were carried out according to
previously described procedures [32,33]. Briefly, superoxide anion production was assayed by monitoring
the superoxide dismutase-inhibitable reduction of ferricytochrome c. Elastase release experiments were
performed using MeO-Suc-Ala-Ala-Pro-Val-p-nitroanilide as the elastase substrate [34].