Fig. 2

S. aureus infects macrophages and maintains intracellular persistence via IL10. (A and B) Confocal microscopy images showing the growth of S. aureus (green) within BMDMs (red) at various time points in the presence of antibiotics (MOI = 10) (Scale bar: 10 μm). Quantitative analysis of intracellular bacterial counts at each time point. (C and D) Flow cytometry analysis of the fluorescence intensity within BMDMs infected with GFP-S. aureus (MOI = 10) over different time points. Quantitative analysis of the proportion of BMDMs infected with GFP-S. aureus among groups. (E, F and G) Flow cytometry analysis of apoptosis in BMDMs infected with S. aureus (MOI = 10) at various time points after treatment with Annexin V-FITC/PI. Quantitative analysis of apoptosis and necrosis rates in BMDMs following intracellular infection with S. aureus (H) ELISA quantification of IL6, TNF-α, IL1β, IL12, IL10, and TGF-β levels in the supernatant of BMDMs infected with S. aureus (MOI = 10) at 0 and 24 h. (I and J) Flow cytometry analysis of intracellular bacterial growth in BMDMs 24 h after infection with GFP-S. aureus (MOI = 10), following transfection with control siRNA or IL10 siRNA and in the presence or absence of added IL10 (1ng/ml). Quantitative analysis of the proportion of BMDMs infected with GFP-S. aureus among groups. Statistical analysis was performed using one-way ANOVA (B, D, F, G) or two-tailed Student’s unpaired t-test (H, J): ns, P > 0.05; * P < 0.05; ** P < 0.01; *** P < 0.001. The data represent the mean ± SD from at least three independent experiments