Abstract
This study was done to determine if the production and metabolism of reactive oxygen species from human neutrophils were modulated by the treatment of interferon-α (IFN-α).
Luminol-dependent Chemiluminescence (LmCL) responses were inhibited by a high concentration of IFN-α (more than 1×104IU/ml) when opsonized zymosan (OZ) and phorbol 12-myristate 13-acetate (PMA) were used as stimulants. However, these responses were increased by 1×103IU/ml of IFN-α with Ca2+ -ionophore A23187 stimulation. Lucigenin-dependent Chemiluminescence (LgCL) responses were inhibited by all concentrations. These findinds suggest the possibility that IFN-α inhibits activation of protein kinase C (PKC), whereas the resultig effect might be due to the inhibition of myeloperoxidese (MPO) degranulation.
Preincubation of human neutrophils with IFN-α for 30, 60 or 120 minutes and subsequent stimulation with OZ, PMA and Ca2+ -ionophore A23187 caused an increase LgCL responses, while inhibiting LmCL responses. These findings suggest that preincubation of human neutrophils with a high concentration of IFN-α might enhance the NADPH-oxidase activity, although a relative increase of LgCL was due to the inhibition MPO degranulation.
