title: Lipoxygenase inhibitors enhance the proliferation of human B cells.
abstract: The addition of drugs which inhibit the lipoxygenase pathways of arachidonic acid metabolism to 5 day cultures of mitogen-stimulated human B cells enhanced the proliferative response more than 10-fold. Several chemically dissimilar lipoxygenase inhibitors increased proliferation in this system, whereas the specific cyclooxygenase inhibitor indomethacin had no effect. A lipoxygenase inhibitor could be added as late as 48 to 72 h after the initiation of culture and still cause a significant increase in B cell proliferation. These drugs increased the proliferation of both peripheral blood B cells and tonsillar B cells activated by Staphylococcus aureus Cowan I or anti-Ig M antibodies, in combination with a crude T cell supernate, a commercial B cell growth factor preparation, or recombinant lymphotoxin. A similar effect was observed in tonsillar B cells purified by counterflow centrifugal elutriation to remove esterase positive accessory cells, suggesting this is a direct effect on the B cell. Lipoxygenase blockade also caused a greater than twofold increase in polyclonal Ig production. The enhanced proliferation caused by lipoxygenase blockade could not be reversed by adding back exogenous leukotrienes or hydroxyeicosatetraenoic acids to the cultures. Furthermore, B cells prelabeled with [3H]arachidonic acid did not produce radiolabeled lipoxygenase metabolites of arachidonic acid under the same culture conditions in which the addition of lipoxygenase inhibitors had a profound effect on proliferation. Thus, lipoxygenase inhibitors markedly stimulate B cell proliferation under a variety of experimental conditions, although the mechanism responsible for this action has not yet been elucidated.
authors.affiliation: Department of Medicine, Medical College of Wisconsin, Milwaukee 53233.
authors.forename: T W
authors.initials: TW
authors.lastname: Behrens
authors.forename: L G
authors.initials: LG
authors.lastname: Lum
authors.forename: E A
authors.initials: EA
authors.lastname: Lianos
authors.forename: J S
authors.initials: JS
authors.lastname: Goodwin
mesh_terms: D015772:4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyrazol-3-amine; D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000328:Adult; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000502:physiology; D016227:Benzoquinones; D002454:Cell Differentiation / Q000187:drug effects; D002648:Child; D016861:Cyclooxygenase Inhibitors; D004306:Dose-Response Relationship, Immunologic; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis; D007213:Indomethacin / Q000494:pharmacology; D015847:Interleukin-4; D007378:Interleukins / Q000494:pharmacology; D007700:Kinetics; D016859:Lipoxygenase Inhibitors; D008213:Lymphocyte Activation / Q000187:drug effects*; D009637:Masoprocol / Q000494:pharmacology; D014066:Palatine Tonsil; D011720:Pyrazoles / Q000494:pharmacology; D011809:Quinones / Q000494:pharmacology; D013205:Staphylococcal Protein A / Q000494:pharmacology
chemical_list: D000276:Adjuvants, Immunologic; D016227:Benzoquinones; D016861:Cyclooxygenase Inhibitors; D007136:Immunoglobulins; D007378:Interleukins; D016859:Lipoxygenase Inhibitors; D011720:Pyrazoles; D011809:Quinones; D013205:Staphylococcal Protein A; D015847:Interleukin-4; D015772:4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyrazol-3-amine; D009637:Masoprocol; C036837:2,3,5-trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1,4-benzoquinone; D007213:Indomethacin