Interleukin-8-induced priming of neutrophil oxidative burst requires sequential recruitment of NADPH oxidase components into lipid rafts
Interleukin-8-induced priming of neutrophil oxidative burst requires sequential recruitment of NADPH oxidase components into lipid rafts
复制标题
DOI：
10.1074/jbc.m506594200
复制
发表时间：
2005-11-04
影响因子：
4.8
通讯作者：
Elbim, C
中科院分区：
文献类型：
--
作者：
Guichard, C;Pedruzzi, E;Elbim, C
产生超氧化物的吞噬细胞NADPH氧化酶由膜结合的黄细胞色素B（558）、胞质因子p47（phox）、p67（phox）、p40（phox）和小的GT3 Rac 2组成，它们在中性粒细胞活化后移位到膜上组装活性复合物。白细胞介素-8（IL-8）不激活NADPH氧化酶，但通过引发机制增强由刺激物如甲酰甲硫氨酰亮氨酰苯丙氨酸（fMLP）诱导的氧化爆发。IL-8对NADPH氧化酶组分在引发过程中的影响从未在人中性粒细胞中研究过。在这里，我们发现在3分钟内，IL-8处理增强了Btk和ERK 1/2依赖的p47（phox）磷酸化，以及黄细胞色素b558，p47（phox）和Rac 2的招募到富含胆固醇的洗涤剂抗性微区（或脂筏）。相反，持续15分钟的IL-8处理未能募集黄细胞色素B（558）、p47（phox）或Rac 2，但确实增强了Btk和p38 MAPK依赖性磷酸化和p67（phox）易位到洗涤剂抗性微区。此外，甲基-β-环糊精，破坏脂筏，抑制IL-8诱导的启动响应fMLP。我们的研究结果表明，IL-8诱导的启动的氧化猝发响应fMLP涉及的NADPH氧化酶组件的中性粒细胞的脂筏中的顺序组装。
The superoxide-producing phagocyte NADPH oxidase consists of a membrane-bound flavocytochrome b(558), the cytosol factors p47(phox), p67(phox), p40(phox), and the small GTPase Rac2, which translocate to the membrane to assemble the active complex following neutrophil activation. Interleukin-8 (IL-8) does not activate NADPH oxidase, but potentiates the oxidative burst induced by stimuli such as formyl-methionyl-leucyl-phenylalanine ( fMLP) via a priming mechanism. The effect of IL-8 on the components of NADPH oxidase during the priming process has never been investigated in human neutrophils. Here we showed that within 3 min, IL-8 treatment enhanced the Btk- and ERK1/2-dependent phosphorylation of p47(phox), as well as the recruitment of flavocytochrome b558, p47(phox), and Rac2 into cholesterol-enriched detergent-resistant microdomains ( or lipid rafts). Conversely, IL-8 treatment lasting 15 min failed to recruit flavocytochrome b(558), p47(phox), or Rac2, but did enhance the Btk- and p38 MAPK-dependent phosphorylation and the translocation of p67(phox) into detergent-resistant microdomains. Moreover, methyl-beta-cyclodextrin, which disrupts lipid rafts, inhibited IL-8-induced priming in response to fMLP. Our findings indicate that IL-8-induced priming of the oxidative burst in response to fMLP involves a sequential assembly of the NADPH oxidase components in the lipid rafts of neutrophils.