In vitro effects of meropenem and imipenem/cilastatin on some functions ofhuman natural effector cells

Meropenem, a new carbapenem antibiotic, was assessed to evaluate its effect s on some functional parameters of human polymorphonuclear (PMN) and natura l killer (NK) cells in comparison with imipenem/cilastatin. Both drugs sign ificantly inhibited PMN phagocytosis and chemotaxis at concentrations of 2, 000 and 4,000 mu g/ml. They affected PMN microbicidal activity, evaluated a gainst Candida albicans, only at 4,000 mu g/ml. A study of the effects of b oth drugs on peripheral NK populations and the human NK line (NK-92) showed that even at 4,000 mu g/ml there was no effect on antitumor activity. Thes e data indicate that meropenem can re-duce some PMN antimicrobial functions only at very high concentrations like imipenem/cilastatin, whereas no conc entration influenced NK activity. Copyright (C) 2000 S. Karger AG. Basel.