As we observed blunted expression of type I IFN stimulated genes (Fig 3), similar numbers of neutrophils in the cecal mucosa but lower levels of MPO (Fig 6A and 6B), a neutrophil activation marker, in the cecum of Stat2-/- mice infected with S. Typhimurium, these results suggest that type I IFNs do not effect the migration of neutrophils to the site of infection but may effect the antimicrobial activity of these cells. This evidence concerns the gene MPO and infection.