NADPH oxidase function and expression in patient and family members. (A) Neutrophil NADPH oxidase activity in response to PMA (200 ng/mL), fMLF (10 μM), or SOZ (2 mg/mL) as indicated, as monitored by cytochrome reduction or isoluminol for extracellular activity (PMA and fMLF, respectively) or luminol for intracellular activity (SOZ). RLU indicates relative light units. Color-coded symbols and bars indicate patient (P, red); mother (M, purple); father (F, green); brother (B, blue); or control (C, black). (Top row) Representative kinetic data; (bottom row) NADPH oxidase activity as the mean ± SD relative to control samples; results of all controls are shown in one bar. Dashed red line indicates background signal for patient neutrophils stimulated with PMA or fMLF in the presence of SOD, or for SOZ, unstimulated cells. PMA and SOZ assays were performed in patient (n = 3), mother (n = 3), father (n = 2), brother (n = 2), and controls (n = 6). *P < .05 NADPH oxidase activity versus controls. For fMLF, superoxide production was measured in the patient (n = 3) and controls (n = 6). (B) Results of a 1-step bactericidal assay at a neutrophil-bacteria ratio = 1:5. Mean ± SD of quadruplicate measurements of bacteria colony-forming units (CFUs) in the absence of neutrophils (blue line), or the presence of control (black line) or patient (red line) neutrophils. *P < .05 for the control versus patient at 20 minutes and 60 minutes. Results for neutrophils treated with the NADPH oxidase inhibitor diphenyliodonium (10 μM) are shown by dashed lines. (C) Immunoblot of NADPH oxidase subunits and densitometry of p40^phox and p67^phox expression (representative of 2 independently obtained sample sets).