Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, UK.
Rheumatology (Oxford). 2012 Jul;51(7):1166-9. doi: 10.1093/rheumatology/ker520. Epub 2012 Feb 20.
Reactive oxygen species (ROS) are implicated in the pathogenesis of SSc. Neutrophils constitute a major source of ROS during inflammation. Here, we examined endogenous and stimulated ex vivo ROS production of SSc neutrophils compared with control neutrophils with and without prior priming with TNF-α.
ROS generation was measured using luminol-enhanced chemiluminescence. Neutrophils isolated from SSc patients and healthy controls were unprimed or were primed with TNF-α. ROS production was stimulated in vitro with phorbol 12-myristate 13-acetate (PMA) and formyl-met-leu-phe (fMLP). To examine the effects of serum mediators on ROS generation, control neutrophils were also stimulated with SSc or control serum.
Neutrophil stimulation with PMA and fMLP resulted in a greater increase in ROS generation in SSc neutrophils compared with controls. However, unstimulated SSc neutrophils generated lower levels of ROS than controls. SSc neutrophils demonstrated an increased response to fMLP in the absence of in vitro TNF-α priming indicating priming of SSc neutrophils in vivo. SSc serum did not stimulate neutrophil ROS generation in vitro.
SSc neutrophils are primed for ROS generation. Neutrophils binding to activated endothelium in SSc, may induce local production of ROS, perpetuating endothelial dysfunction and mediating fibrosis.
活性氧（ROS）参与了硬皮病的发病机制。中性粒细胞在炎症期间是 ROS 的主要来源。在这里，我们比较了 SSc 中性粒细胞与对照中性粒细胞在有无 TNF-α预先刺激的情况下，内源性和体外刺激 ROS 的产生。
使用发光增强化学发光法测量 ROS 的产生。从 SSc 患者和健康对照者中分离出中性粒细胞，不预先刺激或用 TNF-α预先刺激。体外用佛波醇 12-肉豆蔻酸 13-乙酸酯（PMA）和甲酰基甲硫氨酸亮氨酸苯丙氨酸（fMLP）刺激 ROS 产生。为了研究血清介质对 ROS 生成的影响，还刺激对照中性粒细胞用 SSc 或对照血清。
与对照组相比，SSc 中性粒细胞对 PMA 和 fMLP 的刺激导致 ROS 生成增加更大。然而，未刺激的 SSc 中性粒细胞产生的 ROS 水平低于对照组。SSc 中性粒细胞在没有体外 TNF-α预刺激的情况下对 fMLP 表现出增加的反应，表明 SSc 中性粒细胞在体内被预先刺激。SSc 血清不能在体外刺激中性粒细胞 ROS 的产生。
SSc 中性粒细胞被 ROS 生成所激活。与激活的内皮细胞结合的中性粒细胞可能诱导局部 ROS 的产生，使内皮功能障碍和介导纤维化持续存在。
