Superoxide release and NADPH oxidase components in mature human phagocytes: correlation between functional capacity and amount of functional proteins.

We evaluated the interrelationship between the respiratory activity and amount of proteins responsible for this function in normal and subnormal human phagocytes, neutrophils, eosinophils, monocytes, and macrophages. The superoxide-producing capacity was eosinophils > neutrophils > monocytes = macrophages when the cells were stimulated with chemotactic peptide or phorbol ester. Consonant with this finding, the protein content of three essential components of phagocyte oxidase (p22-phox, p67-phox, and p47-phox) was also eosinophils > neutrophils > monocytes = macrophages. On the other hand, the amount of another essential component, gp91-phox, was macrophage > neutrophils > eosinophils > monocytes. These findings together indicate an overall positive interrelationship between protein content and its responsible function, though only gp91-phox was not associated with the functional capacity and low amounts of this component supported the increased respiratory burst activity of eosinophils.