title: Human B lymphocytes possess 5-lipoxygenase activity and convert arachidonic acid to leukotriene B4.
abstract: Incubation of cell sonicates from monoclonal B cells with arachidonic acid led to the formation of leukotriene (LT) B4 and 5-hydroxy-eicosatetraenoic acid (5-HETE). In contrast, stimulation of intact B cells with the calcium ionophore A23187 +/- arachidonic acid did not, under similar conditions, lead to formation of LTB4. The identification of these products was based on reverse phase- and straight phase-HPLC analysis, UV-spectroscopy and gas chromatography-mass spectrometry. Cell sonicates of highly enriched human tonsillar B lymphocytes also converted arachidonic acid to LTB4 and 5-HETE. Activation of these cells with B cell mitogen and cytokines for three days led to an upregulation of 5-lipoxygenase activity. This study provides evidence for the biosynthesis of LTB4 from arachidonic acid in B cell lines and in normal human tonsillar B lymphocytes.
authors.affiliation: Department of Physiological Chemistry, Karolinska Institutet, Stockholm, Sweden.
authors.forename: P J
authors.initials: PJ
authors.lastname: Jakobsson
authors.forename: B
authors.initials: B
authors.lastname: Odlander
authors.forename: D
authors.initials: D
authors.lastname: Steinhilber
authors.forename: A
authors.initials: A
authors.lastname: Rosén
authors.forename: H E
authors.initials: HE
authors.lastname: Claesson
mesh_terms: D001094:Arachidonate 5-Lipoxygenase / Q000378:metabolism*; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D001402:B-Lymphocytes / Q000187:drug effects / Q000201:enzymology* / Q000276:immunology; D002460:Cell Line; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000378:metabolism; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000494:pharmacology; D015850:Interleukin-6 / Q000494:pharmacology; D007975:Leukotriene B4 / Q000096:biosynthesis*; D014066:Palatine Tonsil / Q000276:immunology; D011994:Recombinant Proteins / Q000494:pharmacology
chemical_list: D001095:Arachidonic Acids; D006893:Hydroxyeicosatetraenoic Acids; D007376:Interleukin-2; D015850:Interleukin-6; D011994:Recombinant Proteins; D007975:Leukotriene B4; D016718:Arachidonic Acid; C022022:5-hydroxy-6,8,11,14-eicosatetraenoic acid; D001094:Arachidonate 5-Lipoxygenase