title: Effect of ciprofloxacin on killing of Actinobacillus actinomycetemcomitans by polymorphonuclear leukocytes.
abstract: Actinobacillus actinomycetemcomitans, a pathogen associated with aggressive periodontitis, resists phagocytic killing by polymorphonuclear leukocytes (PMNs). It is susceptible to ciprofloxacin, which PMNs actively accumulate. This study tested the hypothesis that ciprofloxacin-loaded PMNs are more effective at killing A. actinomycetemcomitans than control PMNs. Isolated human PMNs were loaded by brief incubation with 0.5 microg of ciprofloxacin/ml. Opsonized bacteria (ATCC 43718) were incubated at 37 degrees C with control and ciprofloxacin-loaded PMNs and in the presence and absence of 0.5 microg of ciprofloxacin/ml. When assayed at bacteria-to-PMN ratios of 30:1 and 90:1, ciprofloxacin-loaded PMNs killed significantly more bacteria and achieved significantly shorter half times for killing than control PMNs (P < 0.05; Tukey's test). At ratios of 3:1 and 10:1, these differences were not significant.
authors.affiliation: Section of Periodontology, College of Dentistry, The Ohio State University Health Sciences Center, Columbus, Ohio 43218-2357, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Cacchillo
authors.forename: John D
authors.initials: JD
authors.lastname: Walters
mesh_terms: D016976:Aggregatibacter actinomycetemcomitans / Q000187:drug effects* / Q000276:immunology*; D000890:Anti-Infective Agents / Q000494:pharmacology*; D002939:Ciprofloxacin / Q000494:pharmacology*; D015169:Colony Count, Microbial; D006801:Humans; D007111:Immunity, Cellular / Q000187:drug effects*; D066298:In Vitro Techniques; D009504:Neutrophils / Q000187:drug effects* / Q000276:immunology*; D010084:Oxidation-Reduction; D010587:Phagocytosis / Q000187:drug effects*; D016897:Respiratory Burst / Q000187:drug effects
chemical_list: D000890:Anti-Infective Agents; D002939:Ciprofloxacin