Those favorable properties concur with protection by IL-22 as detected in rodent models of infection- and/or tissue damage-driven diseases at host/environment interfaces (4), which include intestinal Citrobacter rodentium (7) as well as lung Klebsiella pneumonia (8) and influenza infections (9), ventilator-induced lung injury (10), experimental colitis (11, 12), and acute liver injury (13, 14). Here, IL22 is linked to infection.