FPR1 and inflammatory response: In the context of pulmonary inflammation, Fpr1−/− mice are protected from cigarette smoking induced emphysematous changes, with associated reduction in neutrophil and macrophage number.33 Furthermore, a model of endotoxin-induced lung injury demonstrated a protective phenotype for Fpr1−/− mice.34 These studies propose an association with exogenous bacterial formylated peptides but no exploration of the effects of endogenous mitochondrial formylated peptides has been described in models of direct pulmonary injury.