title: Interleukin-5 and IL-5 receptor in health and diseases.
abstract: While interleukin-5 (IL-5) is initially identified by its ability to support the growth and terminal differentiation of mouse B cells in vitro into antibody-secreting cells, recombinant IL-5 exerts pleiotropic activities on various target cells including B cells, eosinophils, and basophils. IL-5 is produced by both hematopoietic and non-hematopoietic cells including T cells, granulocytes, and natural helper cells. IL-5 exerts its effects for proliferation and differentiation via receptors that comprise an IL-5-specific α and common β-subunit. IL-5Rα expression in activated B cells is regulated by a complex of transcription factors including E12, E47, Sp1, c/EBPβ, and Oct2. IL-5 signals are transduced through JAK-STAT, Btk, and Ras/Raf-ERK signaling pathways and lead to maintenance of survival and functions of B cells and eosinophils. Overexpression of IL-5 in vivo significantly increases eosinophils and B cells in number, while mice lacking a functional gene for IL-5 or IL-5 receptor display a number of developmental and functional impairments in B cells and eosinophil lineages. In humans, the biologic effects of IL-5 are best characterized for eosinophils. The recent expansion in our understanding of eosinophil development and activation and pathogenesis of eosinophil-dependent inflammatory diseases has led to advance in therapeutic options. Intravenous administration of humanized anti-IL-5 monoclonal antibody reduces baseline bronchial mucosal eosinophils in mild asthma; providing important implications for strategies that inhibit the actions of IL-5 to treat asthma and other allergic diseases.
authors: Department of Immunobiology and Pharmacological Genetics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Japan. takatsuk@med-u-toyama.ac.jp
authors: Kiyoshi
authors: K
authors: Takatsu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004194:Disease; D006262:Health; D006801:Humans; D007109:Immunity; D015848:Interleukin-5 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D053649:Receptors, Interleukin-5 / Q000737:chemistry / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D015848:Interleukin-5; D053649:Receptors, Interleukin-5