title: The functional roles of S1P in immunity.
abstract: The lipid mediator sphingosine-1-phosphate (S1P) is generated within cells from sphingosine by two sphingosine kinases (SPHK1 and SPHK2). Intracellularly synthesized S1P is released into the extracellular fluid by S1P transporters, including SPNS2. Released S1P binds specifically to the G protein-coupled S1P receptors (S1PR1/S1P(1)-S1PR5/S1P(5)), which activate a diverse range of downstream signalling pathways. Recent studies have proposed that one of the central physiological functions of intercellular S1P signalling is in lymphocyte trafficking in vivo because genetic disruption of SPHK1/2, SPNS2 or S1PR1/S1P(1) in mice induces a lymphopenia phenotype. In this review, we discuss the current understanding of intercellular S1P signalling in the context of immunity.
authors.affiliation: Laboratory for Cardiovascular Molecular Dynamics, Riken Quantitative Biology Center (QBiC), Furuedai 6-2-3, Suita, Osaka 565-0874, Japan. y.hisano@riken.jp
authors.forename: Yu
authors.initials: Y
authors.lastname: Hisano
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Nishi
authors.forename: Atsuo
authors.initials: A
authors.lastname: Kawahara
mesh_terms: D000818:Animals; D006801:Humans; D007109:Immunity; D008246:Lysophospholipids / Q000276:immunology* / Q000378:metabolism; D015398:Signal Transduction; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000276:immunology / Q000378:metabolism
chemical_list: D008246:Lysophospholipids; C060506:sphingosine 1-phosphate; D013110:Sphingosine