ROOPEROL, AN INHIBITOR OF CYTOKINE SYNTHESIS, DECREASES THE RESPIRATORY BURST IN HUMAN AND RAT LEUKOCYTES AND MACROPHAGES

LUMINOL-ENHANCED chemiluminescence was measured in fresh whole human b lood, or human neutrophils isolated from heparinized blood, human alve olar macrophages and rat alveolar macrophages stimulated with bacteria l endotoxin (LPS). Tetraacetate esters of rooperol, a dicatechol showi ng anticytokine activity, added to cells simultaneously with LPS inhib ited the respiratory burst. The effective concentrations of rooperol w ere in the range of 1-10 mu M depending on cell type and corresponded well with inhibition of nitric oxide production by rat alveolar macrop hages. Thus rooperol may reduce some effects of excessive phagocytic a ctivity and inflammatory reaction but by quenching free radicals produ ction may also diminish the resistance to bacterial infections.