TABLE 2.

Efficacy of antibiotics against internalized CD E. coli strains in J774-A1 macrophages at 10% Cmax

Antibiotic% Intracellular killing of the indicated E. coli strain at 10% Cmax (mean ± SEM)a
LF82HM580HM605HM615
Ampicillin10.9 ± 7.89.6 ± 11.620.4 ± 8.413.8 ± 15.4
Ciprofloxacin87.6 ± 1.9***90.4 ± 1.0***91.3 ± 4.8***83.8 ± 2.4***
Clarithromycin55.2 ± 6.0***57.5 ± 8.7***33.5 ± 2.6**81.8 ± 2.1***
Rifampin32.8 ± 7.4 **35.8 ± 9.3 **32.6 ± 9.5 **80.2 ± 2.1***
Sulfamethoxazole63.2 ± 6.1**58.7 ± 7.1**39.8 ± 17.0**71.5 ± 17.2***
Tetracycline64.2 ± 6.2***62.4 ± 4.0***44.8 ± 8.3***69.6 ± 8.2***
Trimethoprim50.2 ± 6.7***46.9 ± 6.1***49.1 ± 4.9***61.7 ± 3.1***
  • a Significant differences from antibiotic-free survival rates are indicated as follows: *, P < 0.05; **, P < 0.01; and ***, P < 0.001 (n = 3). Published Cmax values are listed in Table 1.