Molecular characterization and immunological roles of avian IL-22 and its soluble receptor IL-22 binding protein

► Recombinant chicken IL-22 and IL22BP are successfully cloned, expressed and purified. ► Chicken IL-22 did not effect on immune cells. ► Enhanced inflammatory responses by chicken IL-22 were observed in epithelial cells. ► The expression of acute phase reactants was induced by chicken IL-22 in hepatocytes. ► Purified chicken IL22BP neutralized the chicken IL-22 activity.