Effect of AC-1370 on the neutrophil functions

We evaluated the effect of AC-1370, a new injectable cephalosporin, on the neutrophil functions by the methods of polarization and superoxide production measurement. In vitro experiments, AC-1370 enhanced polarization slightly at the concentration of 20 ~ 100 jug/ml and depressed 30% of control at the high concentration of 500 μg/ml. AC-1370 enhanced superoxide production activity 20 ~ 30% at the concentration of 1 ~ 500 μg/ml. No appreciable effect on polarization and superoxide production activity could be detected for cefazolin (CEZ) and cefoperazone (CPZ). In the evaluation of the change of neutrophil polarization and superoxide production activity of 4 or 5 healthy volunteers 1 hr or 4 hrs after intravenous drip infusion of 2 g AC-1370, CEZ or CPZ, AC-1370 showed a tendency to increase both functions, and CEZ and CPZ did not showed any appreciable change. In patients who received AC-1370 (2 g/day), CEZ (4 g/day) or CPZ (4 g/day) for one or two weeks, slight increase of polarization and marked enhancement of superoxide production activity were seen in patients treated with AC-1370. No change was seen in patients treated with CEZ or CPZ. AC-1370 have been confirmed to have a higher in vivo effect than that expected from in vitro antibacterial activity. It was considered as one of this mechanism that AC-1370 could directly potentiate neutrophil functions resulting in enhancement of host defense activity.