title: Cyclic AMP: master regulator of innate immune cell function.
abstract: Cyclic adenosine monophosphate (cAMP) was the original "second messenger" to be discovered. Its formation is promoted by adenylyl cyclase activation after ligation of G protein-coupled receptors by ligands including hormones, autocoids, prostaglandins, and pharmacologic agents. Increases in intracellular cAMP generally suppress innate immune functions, including inflammatory mediator generation and the phagocytosis and killing of microbes. The importance of the host cAMP axis in regulating antimicrobial defense is underscored by the fact that microbes have evolved virulence-enhancing strategies that exploit it. Many clinical situations that predispose to infection are associated with increases in cAMP, and therapeutic strategies to interrupt cAMP generation or actions have immunostimulatory potential. This article reviews the anatomy of the cAMP axis, the mechanisms by which it controls phagocyte immune function, microbial strategies to dysregulate it, and its clinical relevance.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health, System, Ann Arbor, Michigan, USA.
authors.forename: Carlos H
authors.initials: CH
authors.lastname: Serezani
authors.forename: Megan N
authors.initials: MN
authors.lastname: Ballinger
authors.forename: David M
authors.initials: DM
authors.lastname: Aronoff
authors.forename: Marc
authors.initials: M
authors.lastname: Peters-Golden
mesh_terms: D000818:Animals; D000242:Cyclic AMP / Q000502:physiology*; D006801:Humans; D007113:Immunity, Innate; D010587:Phagocytosis / Q000502:physiology*; D015398:Signal Transduction
chemical_list: D000242:Cyclic AMP