Inhibition of Granulocyte Adherence by Ethanol, Prednisone, and Aspirin, Measured with an Assay System

A simple, rapid, in vitro assay was developed to study granulocyte adherence, an important component of the inflammatory reaction. Heparinized whole blood is filtered through nylon fiber packed in Pasteur pipettes, and the percentage of granulocytes adhering is calculated. Test variability from morning to evening, before and after meals, and on successive days is less than 10 per cent. In vitro exposure of whole blood to ethanol concentrations varying from 100 to 1000 mg per 100 ml caused a dose-dependent, significant inhibition of adherence (16–87 per cent, p<0.05), but incubation with sodium salicylate (5 to 50 mg per 100 ml) or hydrocortisone sodium succinate (500 to 3000 μg per 100 ml) had no effect. In all volunteers receiving 40 mg of prednisone or 1.2 g of aspirin, impaired adherence developed, suggesting that glucocorticoids and salicylates may affect adherence in vivo by inducing an inhibitor. The anti-inflammatory effect of salicylates, hydrocortisone and ethanol may be secondary to their inhibition of granulocyte adherence. (N Engl J Med 291:642–646, 1974)