Miconazole and amphotericin B alter polymorphonuclear leukocyte functions and membrane fluidity in similar fashions.

The influence of miconazole on polymorphonuclear leukocytes (PMN) was investigated and compared with that of amphotericin B (AmB). Human PMN were preincubated in vitro with miconazole or AmB at therapeutically attainable concentrations in plasma, and their chemotactic functions were assessed with the synthetic chemotactic peptide N-formylmethionyl-leucyl-phenylalanine (FMLP). Changes in membrane fluidity of PMN were examined by an excimer-forming lipid technique. Adherence of PMN was measured by a nylon fiber column method. Miconazole and AmB pretreatment irreversibly depressed PMN random migration and chemotaxis under agarose but did not influence superoxide anion production. Both miconazole and AmB increased PMN adherence. Miconazole and AmB lowered the binding affinity of FMLP receptors on PMN and decreased the membrane fluidity in a similar manner. These results demonstrate that miconazole and AmB alter selected in vitro membrane properties of human PMN.