Phagocytic function and antibody-dependent cellular cytotoxicity of human neutrophils in the presence of N-formimidoyl thienamycin.

The efficacy of an antibiotic in the treatment of bacterial infections depends upon the interactions of the drug, bacteria and phagocytes. We have studied "in vitro" the effect of N-formimidoyl thienamycin (Imipenem), a novel beta-lactamic antibiotic, on the phagocytic function and antibody-dependent cellular cytotoxicity of human neutrophil leukocytes. The incubation of these cells with 50 micrograms/ml of Imipenem similar to the therapeutic levels reached in plasma results in an increase of their adherence capacity to nylon fiber and to substrate, induced mobility or chemotaxis, opsonization, phagocytosis of Candida albicans (with serum, with decomplementarized serum and without serum) and latex beads, candidicidal power and the capacity of NBT reduction. Imipenem at this dose also presents chemoattractant power for neutrophils and enhances the antibody-dependent cellular cytotoxicity (ADCC).