title: Leukotriene B4 induces interleukin 5 generation from human T lymphocytes.
abstract: Leukotriene B4 (LTB4) has been shown to affect several interleukin (IL)-linked functions of human lymphocytes. In this study, we investigated whether LTB4 regulates IL-5 generation from human T cells and subsequently modulates eosinophil functions. Preincubation of T cells with very low concentrations (10(-12) to 10(-8) M) of LTB4 induced concentration-dependent IL-5 production, the event occurring after the first 24 h of cultivation. However, direct action of LTB4 to IL-5 generation is strictly dependent on a preincubation with appropriate concentration of LTB4. In contrast, the stereoisomer of LTB4, 5S,12S-dihydroxy-6,8,10,14-eicosatetraenoic acid showed no enhancement of IL-5 production. IL-5 released from LTB4-primed T cells elicited sustained viability of mature eosinophils and reduced the content of eosinophil cationic protein in their crystalloid matrix by degranulation. These data suggest that LTB4 induces bioactive IL-5 production from T cells and that the released IL-5 modulates eosinophil functions which might play a crucial role in eosinophil-linked allergic inflammatory process.
authors.affiliation: U365-Institut National de la Santé et de la Recherche Médical, (INSERM), Interférons et Cytokines, Institut Curie, Paris.
authors.forename: K A
authors.initials: KA
authors.lastname: Yamaoka
authors.forename: J P
authors.initials: JP
authors.lastname: Kolb
mesh_terms: D001798:Blood Proteins / Q000378:metabolism; D015536:Down-Regulation; D047091:Eosinophil Granule Proteins; D004804:Eosinophils / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D015848:Interleukin-5 / Q000096:biosynthesis*; D007700:Kinetics; D007975:Leukotriene B4 / Q000737:chemistry / Q000494:pharmacology*; D012260:Ribonucleases; D013237:Stereoisomerism; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology
chemical_list: D001798:Blood Proteins; D047091:Eosinophil Granule Proteins; D015848:Interleukin-5; D007975:Leukotriene B4; D012260:Ribonucleases