In comparison to WT mice, Il1r1-/- mice had significantly decreased abundance of neutrophil growth factors G-CSF and GM-CSF and lower levels of the neutrophil chemokine CXCL1 at day 1 post-infection, a timepoint that precedes early bacterial control in WT mice between days 3 and 5 (Figs 5B–5D and 4E). Here, CSF2 is linked to infection.