Identification of distinct activation pathways of the human neutrophil NADPH-oxidase.
Identification of distinct activation pathways of the human neutrophil NADPH-oxidase.
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DOI：
10.4049/jimmunol.137.9.2925
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发表时间：
1986-11
影响因子：
4.4
通讯作者：
I. Maridonneau-Parini;S. Tringale;A. Tauber
中科院分区：
文献类型：
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作者：
I. Maridonneau-Parini;S. Tringale;A. Tauber
人中性粒细胞 NADPH 氧化酶的刺激是由多种激动剂启动的，这些激动剂似乎利用了不止一种激活途径。我们发现调理后的酵母聚糖 (OZ) 通过与佛波醇肉豆蔻酸酯乙酸酯 (PMA) 不同的机制刺激 O2- 释放。 PMA 与 OZ 刺激的不同之处在于，它对 H-7（一种蛋白激酶抑制剂）抑制 O2 释放的敏感性以及缺乏 PMA 引发的放射性标记花生四烯酸 ([3H]AA) 从预标记细胞中的释放。 Mepacrine（一种磷脂酶抑制剂）对 O2 生成和 [3H]AA 释放具有平行的剂量反应抑制作用，而 Mepacrine 并未显着抑制 PMA 诱导的 O2 生成，这一发现表明 AA 释放与 OZ 刺激细胞中 O2 生成有关。磷脂酶 A2 (PLA2) 在 AA 释放中的特异性参与通过缺乏 [3H]油酸释放来表明，而完整细胞中的 PLA2 不会释放油酸。 [3H]AA由磷脂酰肌醇和磷脂酰胆碱释放，不伴随形成[3H]-花生四烯酰磷脂酸，从而消除了磷脂酶C的参与；以及对溴苯甲酰溴（一种特定的 PLA2 抑制剂）对 [3H]AA 释放的抑制。 AA 代谢抑制剂（BW755C、乙酰水杨酸和吲哚美辛）减少 O2- 形成，进一步支持了 AA 释放与 O2- 生成之间的联系。 OZ 刺激的细胞中的 [3H]AA 释放（如 O2 生成）是钙依赖性的，这进一步将 OZ 与钙非依赖性 PMA 激活区分开来。这些研究总体表明 OZ 对 NADPH 氧化酶的刺激与 PMA 不同，因为颗粒刺激是 PLA2 介导的并且独立于蛋白激酶 C。
The stimulation of the human neutrophil NADPH-oxidase is initiated by a variety of agonists, which appear to utilize more than one activation pathway. We have discerned that opsonized zymosan (OZ) stimulates O2- release by a mechanism distinct from that of phorbol myristate acetate (PMA). PMA differs from OZ stimulation in its susceptibility to H-7 (a protein kinase inhibitor) inhibition of O2- release and the lack of PMA-initiated release of radiolabeled arachidonic acid ([3H]AA) from prelabeled cells. That AA release was linked to O2- generation in OZ-stimulated cells was suggested by the finding that mepacrine, a phospholipase inhibitor, exhibits parallel dose response inhibition for both O2- generation and [3H]AA release, whereas mepacrine did not significantly inhibit the O2- generation induced by PMA. The specific involvement of phospholipase A2 (PLA2) in the release of AA was indicated by the lack of release of [3H]oleate, which is not released by PLA2 in intact cells; [3H]AA released from phosphatidylinositol and phosphatidylcholine and not accompanied by the formation of [3H]-arachidonyl phosphatidic acid, thus eliminating the involvement of phospholipase C; and the inhibition of [3H]AA release by p-bromophenacyl bromide, a specific PLA2 inhibitor. The reduction of O2- formation by inhibitors of AA metabolism (BW755C, acetylsalicylic acid, and indomethacin) further supports a linkage between AA release and O2- generation. That [3H]AA release, like O2- generation, in OZ-stimulated cells was calcium dependent further differentiates OZ from calcium-independent PMA activation. These studies in toto suggest that OZ stimulation of the NADPH-oxidase differs from PMA, in that the particulate stimulus is PLA2 mediated and independent of protein kinase C.