MPO and infection: The extent of lung pathology and inflammation was not different between these mouse strains at either 12 or 42 h post infection (Figure S2), as reflected by lung pathology scores (Figure 2B), myeloperoxidase (MPO) levels in whole lung homogenates (reflecting neutrophil influx, Figure 2C) and lung cytokine and chemokine levels (tumor necrosis factor (TNF)α, interleukin (IL)-1β, IL-6, C-X-C motif chemokine ligand (CXCL)1 and CXCL2, Figure 2D).