Updated publication reference for PubMed record(s): 31308090. Lung neutrophils are causally associated with IAV-induced disease severity. Less is known about the repertoire of lethal IAV-associated neutrophil proteins or about how global changes in different neutrophil compartments are coordinated following lethal IAV infection. Here, we use semi-quantitative proteomics to characterize dynamic alterations in BM, blood and lung neutrophils at homeostasis or following a lethal IAV infection, with a secondary aim of identifying lung neutrophil-derived proteins which are selectively induced following IAV infection. Our findings identify bone marrow neutrophil maturation as the key site of anti-viral activity induction, with further upregulation or release of both anti-viral and antimicrobial effectors occurring following lung tissue infiltration.