In vitro and ex vivo effects of recent and new macrolide antibiotics on chemotaxis of human polymorphonuclear leukocytes.

The effects of five macrolide antibiotics: erythromycin, josamycin, miokamycin, roxithromycin and rokitamycin, on human polymorphonuclear leukocyte (PMN) chemotaxis was studied in vitro and ex vivo. At therapeutic concentrations none of the antibiotics tested affected in vitro PMN chemotaxis. In vitro, erythromycin, josamycin, miokamycin, roxithromycin and rokitamycin decreased PMN chemotaxis significantly only at the concentration of 10 mg/l, which is not usually reached in vivo. Ex vivo studies after the ingestion of therapeutic doses of erythromycin, josamycin, miokamycin and roxithromycin by five volunteers showed a significant effect on PMN chemotaxis. However, further studies are needed to confirm and better evaluate the clinical significance of recent and novel macrolides on PMN chemotaxis.