Synergistic effect of azithromycin on the phagocytic killing of Staphylococcus aureus by human polymorphonuclear leukocytes.
Many macrolides have been shown to affect the interaction between bacteria and various immune defense mechanisms, such as chemotaxis, accumulation, and bioactivity within phagocytic cells. The interaction of azithromycin with human polymorphonuclear leukocytes (PMNs) was studied in vitro and compared with the interactions between other macrolides and PMNs. The opsonophagocytic killing of Staphylococcus aureus was synergistically enhanced by azithromycin at concentrations below and above the minimal inhibitory concentration, with a reduction of up to 2.82 log10 cfu/ml with 2 mg/ml of azithromycin. Other macrolides were effective only at subinhibitory concentrations. The beneficial azithromycin-leukocyte interaction may explain azithromycin's efficacy against intracellular pathogens.
Herrera-Insúa
I
I
Departamento de Microbiología, Facultad de Medicina, Universidad Complutense de Madrid, Spain.
Pérez
P
P
Ramos
C
C
Martínez
P
P
Gómez-Lus
M L
ML
Prieto
J
J
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017963:Azithromycin / Q000494:pharmacology*; D006801:Humans; D009504:Neutrophils / Q000187:drug effects* / Q000502:physiology; D010587:Phagocytosis / Q000187:drug effects*; D013211:Staphylococcus aureus
D000900:Anti-Bacterial Agents; D017963:Azithromycin