Fig. 4
Mortality of macrophages over time. a, b Representative flow cytometry histograms of PI staining of the macrophages 6 h post-infection with initial bacterial inoculum sizes of 104 (A) or 107 (B) CFU/mL without cephalexin. The PI- and PI+ populations are separated. c Macrophage death following 6 h of exposure of macrophages to different initial inoculum sizes of S. aureus without cephalexin. Initial MOI are indicated below the bars and the actual bacteria to macrophages ratio at 6 h on the right. Data are presented as mean values ± SD, *p < 0.05, **p < 0.01, ***p < 0.001/ n = 3. d, e Macrophage death over time following exposure of macrophages to initial bacterial inoculum sizes of 105 (D) or 107 (E) CFU/mL and to different concentrations of cephalexin. Cephalexin concentrations are expressed as multiples of the MIC (cephalexin MIC = 8 μg/mL). Each symbol represents the mean of results from three experiments