The effects of smoking and zinc on the oxidative reactions of human neutrophils.

Human neutrophils in whole blood and after isolation were examined for their capacity to produce superoxide anions when stimulated by zymosan. The isolation procedure caused neutrophils to lose some of this capacity. The neutrophils of smokers produced less particle-stimulated superoxide than those of non-smokers when the whole blood method was used but not when using isolated cells. Zinc inhibited this aspect of the respiratory burst of isolated neutrophils but enhanced it when the whole blood method was used. We emphasize the importance of methodology when interpreting results.