title: Myeloid 12/15-LOX regulates B cell numbers and innate immune antibody levelsin vivo.
abstract: Background. The myeloid enzyme 12/15-lipoxygenase (LOX), which generates bioactive oxidized lipids, has been implicated in numerous inflammatory diseases, with several studies demonstrating an improvement in pathology in mice lacking the enzyme. However, the ability of 12/15-LOX to directly regulate B cell function has not been studied.Methods.The influence of 12/15-LOX on B cell phenotype and function, and IgM generation, was compared using wildtype (WT) and 12/15-LOX (Alox15-/-) deficient mice. The proliferative and functional capacity of splenic CD19+B cells was measuredin vitroin response to various toll-like receptor agonists.Results. WT andAlox15-/-displayed comparable responses. Howeverin vivo, splenic B cell numbers were significantly elevated inAlox15-/-mice with a corresponding elevation in titres of total IgM in lung, gut and serum, and lower serum IgM directed against the 12/15-LOX product, 12-hydroxyeicosatetraenoic acid-phosphatidylethanolamine (HETE-PE).Discussion.Myeloid 12/15-LOX can regulate B cell numbers and innate immune antibody levelsin vivo, potentially contributing to its ability to regulate inflammatory disease. Furthermore, the alterations seen in 12/15-LOX deficiency likely result from changes in the equilibrium of the immune system that develop from birth. Further studies in disease models are warranted to elucidate the contribution of 12/15-LOX mediated alterations in B cell numbers and innate immune antibody generation to driving inflammationin vivo.
authors.affiliation: Systems Immunity Research Institute, Cardiff University, Cardiff, UK.|Institute of Infection & Immunity, Cardiff University, Cardiff, UK.
authors.forename: Sarah N
authors.initials: SN
authors.lastname: Lauder
authors.affiliation: Systems Immunity Research Institute, Cardiff University, Cardiff, UK.|Institute of Infection & Immunity, Cardiff University, Cardiff, UK.
authors.forename: Victoria J
authors.initials: VJ
authors.lastname: Tyrrell
authors.affiliation: Systems Immunity Research Institute, Cardiff University, Cardiff, UK.|Institute of Infection & Immunity, Cardiff University, Cardiff, UK.
authors.forename: Keith
authors.initials: K
authors.lastname: Allen-Redpath
authors.affiliation: Systems Immunity Research Institute, Cardiff University, Cardiff, UK.|Institute of Infection & Immunity, Cardiff University, Cardiff, UK.
authors.forename: Maceler
authors.initials: M
authors.lastname: Aldrovandi
authors.affiliation: Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, UK.
authors.forename: David
authors.initials: D
authors.lastname: Gray
authors.affiliation: Systems Immunity Research Institute, Cardiff University, Cardiff, UK.|Institute of Infection & Immunity, Cardiff University, Cardiff, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Collins
authors.affiliation: Systems Immunity Research Institute, Cardiff University, Cardiff, UK.|Institute of Infection & Immunity, Cardiff University, Cardiff, UK.
authors.forename: Simon A
authors.initials: SA
authors.lastname: Jones
authors.affiliation: Systems Immunity Research Institute, Cardiff University, Cardiff, UK.|Institute of Infection & Immunity, Cardiff University, Cardiff, UK.
authors.forename: Philip R
authors.initials: PR
authors.lastname: Taylor
authors.affiliation: Systems Immunity Research Institute, Cardiff University, Cardiff, UK.|Institute of Infection & Immunity, Cardiff University, Cardiff, UK.
authors.forename: Valerie
authors.identifier: 0000-0003-4089-8460
authors.initials: V
authors.lastname: O'Donnell
keywords: B cells; inflammation; lipoxygenase