Figure 10

(A) Kinetics of association of CFSE-stained S. pyogenes by human neutrophils. Neutrophils and CFSE-stained S. pyogenes were incubated for 5, 10, 20, 30, 60 or 90 min before the reaction was stopped by adding ice-cold PBS and samples were fixed. Flow cytometry was performed using "cell settings" showing only fluorescence associated with neutrophils. Values are expressed as mean ± standard deviation and are obtained from three different experiments carried out with neutrophils isolated from three different donors. (B) The amount of S. pyogenes associated with neutrophils at different timepoints of incubation. The mean fluorescence intensity (MFI) value associated with neutrophils (cell setting) was divided with the MFI for S. pyogenes (bacterial settings) in each experiment. Values are expressed as mean ± standard deviation and are obtained from three different experiments carried out with neutrophils from three different donors.