Effects of AC-1370, a new semisynthetic cephalosporin, on phagocyte functions.

The effects of a new semisynthetic cephalosporin, AC-1370, on phagocyte functions were compared with those of cefoperazone. AC-1370 augmented phagocytosis by mouse macrophages in vitro and in vivo, by mouse neutrophils in vivo, and by human neutrophils in vitro. Cefoperazone suppressed phagocytosis by mouse macrophages and neutrophils. Random migration and chemotaxis of mouse and human neutrophils were increased by the addition of AC-1370. Nitroblue tetrazolium reduction by human neutrophils was enhanced by the addition of AC-1370. Intracellular killing of bacteria by macrophages was also enhanced by AC-1370. Further, bactericidal effects of AC-1370 against Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae were augmented when they were each cultured with mouse or human leukocytes. These results suggest that AC-1370 is an unique beta-lactam antibiotic which has a potentiating effect on phagocyte functions as well as a bactericidal effect.