Abstract Studies on Interlukin-4 (IL-4) disclosed great deal of information about its various
physiological and pathological roles. All these roles depend upon its interaction and
signaling through either type-I (IL-4Rα/common γ-chain) or type-II (IL-4Rα/IL-13Rα)
receptors. Another cytokine, IL-13, shares some of the functions of IL-4, because both
cytokines use a common receptor subunit, IL-4Rα. Here in this review, we discuss the
structural details of IL-4 and IL-4Rα subunit and the structural similarities between IL-4 and …