Neutrophil depletion prior to infection reduced clearance of S. pneumoniae in WT mice (Fig. 5A), suggesting a protective role at early time points, as others have shown.19 In Il10−/− mice, neutrophil depletion had a similar impact, resulting in increased S. pneumoniae burdens compared with nondepleted mice (Fig. 5A). Here, IL10 is linked to infection.