The effect of a therapeutic doxycycline concentration on polymorphonuclear leukocyte migration in vitro

Tetracyclines, and especially doxycycline, have been reported to inhibit polymorphonuclear leukocyte (PMN) migration. The effect of a therapeutic doxycycline concentration (4.33 micrograms/ml) on PMN migration in vitro was tested with the leading-front technique. No significant effect could be demonstrated on PMN chemokinesis and chemotaxis. It is thus concluded that the effect of therapeutic doxycycline concentrations on PMN migration is negligible. This conclusion has a bearing upon the choice of antimicrobial therapy.