title: Interleukin 1 signaling occurs exclusively via the type I receptor.
abstract: Two receptors for the proinflammatory cytokine interleukin 1 (IL-1) have been cloned and characterized biochemically. While it has been well established that the type I (80-kDa) IL-1 receptor can mediate responses to IL-1, the function of the type II (60-kDa) IL-1 receptor has been unknown. In this manuscript we describe experiments designed to ask whether the type II receptor is capable of delivering a biological signal. We have examined two types of experimental situation: responses to IL-1 in cells which express predominantly the type II receptor, and responses to IL-1 which have been suggested previously in the literature to be mediated by type II receptors. In both situations we find that the responses instead are mediated via type I receptors. A blocking antibody against the type II receptor never inhibits, and in fact sometimes enhances, the responses. We conclude that a very small number of type I receptors is sufficient to mediate all of the actions of IL-1 which we have examined here and that the function of the type II receptor may not be to transduce signals.
authors.affiliation: Department of Molecular Biology, Immunex Research and Development Corporation, Seattle, WA 98101.
authors.forename: J E
authors.initials: JE
authors.lastname: Sims
authors.forename: M A
authors.initials: MA
authors.lastname: Gayle
authors.forename: J L
authors.initials: JL
authors.lastname: Slack
authors.forename: M R
authors.initials: MR
authors.lastname: Alderson
authors.forename: T A
authors.initials: TA
authors.lastname: Bird
authors.forename: J G
authors.initials: JG
authors.lastname: Giri
authors.forename: F
authors.initials: F
authors.lastname: Colotta
authors.forename: F
authors.initials: F
authors.lastname: Re
authors.forename: A
authors.initials: A
authors.lastname: Mantovani
authors.forename: K
authors.initials: K
authors.lastname: Shanebeck
mesh_terms: D000818:Animals; D002460:Cell Line; D016207:Cytokines / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D051379:Mice; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017472:Receptors, Interleukin-1 / Q000032:analysis / Q000502:physiology*; D015398:Signal Transduction; D014407:Tumor Cells, Cultured
chemical_list: D016207:Cytokines; D007375:Interleukin-1; D012333:RNA, Messenger; D017472:Receptors, Interleukin-1