FIG. 4.

GAS LTA d-alanylation decreases susceptibility to neutrophil killing. (A) Phagocytosis and killing kinetics of WT and ΔdltA mutant GAS by human neutrophils at a bacteria:cell ratio of 1:10. The values represent the means and standard deviations of three independent experiments (*, P < 0.05, two-tailed t test). (B) Human neutrophil phagocytosis of fluorescence-tagged GAS. The percentage of neutrophils with intracellular bacteria is depicted (200 cells examined per sample); the graph shows mean values ± standard deviations in one representative study of three experiments with similar results.