IFNL1 and susceptibility to pneumonia measurement: Studies have also shown that IFN-λ1 reduces lung eosinophilia and inhibits the release of IL-4, IL-5, and IL-13 from T cells after treatment of mice with pneumonia with a recombinant adenovirus expressing human IFN-λ1, demonstrating its ability to attenuate the lung inflammatory response (82, 83).