Prolonged Recombinant Interferon-? Therapy in Chronic Granulomatous Disease: Evidence Against Enhanced Neutrophil Oxidase Activity

Recombinant intetferon-y (rlFN-y) therapy has become an effective form of prophylaxis for patients with chronic granulomatous disease (CGD). Preliminary studies with CGD suggested that r1FN-y treatment enhanced phagocyte oxidase activity and increased superoxide (O,-) production. We evaluated several aspects of neutrophil NADPH oxidase activity in 19 CGD patients (representing all four known types of CGD) receiving prolonged rlFN-y therapy (6 to 27 months). In contrast to earlier studies, we failed t o detect any improvement in neutrophil NADPH oxidase activity in 18 of the 19 CGD patients as determined by (1) intact cell 0,production (continuous assay), (2) nitroblue tetrazolium (NBT) staining, (3) cytochrome b, spectroscopy, and (4) activity levels of cytosol and membrane oxidase components using a cell-free activation system. One patient with a variant form of X-linked CGD had a transient increase in neutrophil 0,production