出版社：American Society for Biochemistry and Molecular Biology
摘要：Leukotriene B4 (LTB4) biosynthesis by polymorphonuclear leukocytes(PMNs) is an important factor of inflammatory responses. PMNsalso release LTA4, an unstable intermediate that can be takenup by neighboring cells and metabolized into LTC4. Most studiesof LT synthesis have been carried out using human PMNs, butvery little information is available about mouse PMNs. Mousebone marrow PMNs were found to synthesize eicosanoids upon stimulationwith A23187, fMLP, or zymosan. The major eicosanoids producedare LTB4 and 5-hydroxyeicosatetraenoic acid, with some nonenzymaticproducts of LTA4 hydrolysis. No cysteinyl leukotrienes wereproduced, in contrast to what was observed with human bloodneutrophil preparations. Human megakaryoblast-like MEG-01 cellssynthesized thromboxane B2 and prostaglandin E2 in responseto A23187 but produced no 5-lipoxygenase (5-LO)-derived eicosanoids.When mouse bone marrow cells (mBMCs) and MEG-01 cells were stimulatedduring coincubation, LTC4 and LTD4 were produced. Mouse peritonealmacrophages from 5-LO-deficient mice were able to synthesizeLTC4 when incubated with mBMCs from wild-type mice, demonstratingtranscellular exchange of LTA4 from mBMCs into murine peritonealmacrophages. These data demonstrate that murine bone marrowPMNs are a valid model for the study of LT biosynthesis, whichnow offers the possibility to investigate specific biochemicalpathways through the use of transgenic mice.Supplementary key words murine neutrophils • leukotriene B4 • leukotriene C4 • MEG-01 cells • mass spectrometry
Abbreviations: AA, arachidonic acid; COX, cyclooxygenase; cPLA2, cytosolic phospholipase A2; cys-LT, cysteinyl leukotriene; 5-HETE, 5-hydroxyeicosatetraenoic acid; LC-MS/MS, liquid chromatography-tandem mass spectrometry; 5-LO, 5-lipoxygenase; LT, leukotriene; mBMC, mouse bone marrow cell; PG, prostaglandin; PMN, polymorphonuclear leukocyte; TX, thromboxane
, cytosolic phospholipase A2; cys-LT, cysteinyl leukotriene; 5-HETE, 5-hydroxyeicosatetraenoic acid; LC-MS/MS, liquid chromatography-tandem mass spectrometry; 5-LO, 5-lipoxygenase; LT, leukotriene; mBMC, mouse bone marrow cell; PG, prostaglandin; PMN, polymorphonuclear leukocyte; TX, thromboxane
