Ring W L, Riddick C A, Baker J R, Munafo D A, Bigby T D
Department of Medicine, University of California, San Diego, USA.
Am J Physiol. 1996 Jul;271(1 Pt 1):C372-7. doi: 10.1152/ajpcell.1996.271.1.C372.
Previous studies in mononuclear phagocytes have shown that macrophages have substantially greater 5-lipoxygenase activity than monocytes and that this is associated with greater amounts of 5-lipoxygenase and its activating protein (FLAP). The aim of this study was to examine the effect of mononuclear phagocyte maturation in vitro on 5-lipoxygenase expression. At baseline, monocytes had significant 5-lipoxygenase activity, but then lost all detectable 5-lipoxygenase activity over 7 days. Immunoblot and Northern blot analysis revealed that immunoreactive protein and mRNA for both 5-lipoxygenase and FLAP were significantly decreased over time. These studies demonstrate that in vitro differentiation of monocytes into a macrophage phenotype is not accompanied by the enhanced expression of 5-lipoxygenase and FLAP seen in macrophages derived from in vivo sources. In fact, baseline expression of 5-lipoxygenase and FLAP by monocytes is lost in vitro. These studies have clear implications for the use of cultured monocytes as a model of macrophages, and they also further our understanding of the regulation of the 5-lipoxygenase pathway.
先前针对单核吞噬细胞的研究表明，巨噬细胞的5-脂氧合酶活性比单核细胞显著更高，且这与更多量的5-脂氧合酶及其激活蛋白（FLAP）相关。本研究的目的是检测体外单核吞噬细胞成熟对5-脂氧合酶表达的影响。在基线时，单核细胞具有显著的5-脂氧合酶活性，但在7天内失去了所有可检测到的5-脂氧合酶活性。免疫印迹和Northern印迹分析显示，5-脂氧合酶和FLAP的免疫反应性蛋白及mRNA随时间显著减少。这些研究表明，单核细胞在体外分化为巨噬细胞表型时，并不会伴随在源自体内的巨噬细胞中所见的5-脂氧合酶和FLAP表达增强。事实上，单核细胞中5-脂氧合酶和FLAP的基线表达在体外会丧失。这些研究对于将培养的单核细胞用作巨噬细胞模型具有明确的意义，同时也增进了我们对5-脂氧合酶途径调控的理解。
