A recent study in mice has revealed a protective role for IL-33 in ALI, demonstrating that IL-33-mediated control of inflammation involves the stimulation of IL-13 secretion by ST2+ Tregs, which reduces the infiltration of inflammatory monocytes and local inflammatory cytokines, such as IL-6 and granulocyte-colony stimulating factor (G-CSF) (97). The gene discussed is IL33; the disease is acute respiratory distress syndrome.