IL-4 receptor mutations

IL-4 plays an important role in regulating immune responses. Distinct signa ling pathways, including those for gene activation and cell differentiation and those for cell proliferation and protection from apoptosis, are initia ted from the receptor complex for IL-4 following ligand-receptor engagement . Several advances have been made in our understanding of how distinct func tions of IL-4 are mediated. Most of these studies employed artificial mutat ions of the IL-4-receptor a chain using site-directed mutagenesis and/or de letional mutation. In addition, naturally occurring mutations of the IL-4-r eceptor a chain have been identified and implicated as a genetic predisposi tion for allergic disorders. The results of these studies suggest a modular organization of the receptor and an independent regulation of gene activat ion and cell growth.