Chimeric polypeptide antagonists that include an interleukin-4 (IL-4)
mutein linked to an interleukin-9 (IL-9) mutein are provided, as are
polynucleotides encoding the IL-4 and IL-9 chimeric mutein antagonists.
Also provided are methods of using the chimeric mutein antagonists and
encoding polypeptides to reduce or inhibit the responsiveness of a cell
to a cytokine such as IL-4, IL-9 and/or interleukin-13. Methods using the
compositions to treat disorders such as pulmonary disorders (e.g.,
asthma) also are provided.