CYP1A1 and infection: Decreased lung damage in Cyp1–/– mice was consistent with reduced morbidity and increased survival upon infection (Fig. 2f, g). We also detected a significantly dampened proinflammatory response in Cyp1–/– mice upon influenza virus infection, characterised by reduced levels of pulmonary immune cell recruitment, reduced early IFN production, lower concentrations of proinflammatory cytokines and chemokines in the BALF, and reduced immune cell distribution in the lung parenchyma (Extended Data Fig. 3b-e).