PKD regulates actin polymerization, neutrophil deformability, and transendothelial migration in response to fMLP and trauma
PKD regulates actin polymerization, neutrophil deformability, and transendothelial migration in response to fMLP and trauma
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DOI：
10.1002/jlb.4a0617-251rr
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发表时间：
2018-09-01
影响因子：
5.5
通讯作者：
Paschke, Stephan
中科院分区：
文献类型：
--
作者：
Wille, Christoph;Eiseler, Tim;Paschke, Stephan
中性粒细胞是先天免疫防御和宿主对物理创伤反应的重要介质。由于中性粒细胞对损伤部位的异常浸润在创伤后会引起不良反应，我们研究了中性粒细胞浸润如何在细胞水平上进行调节。我们的数据表明，蛋白激酶D（PKD）是一个重要的调节中性粒细胞迁移。PKD磷酸化Cofilin磷酸酶Slingshot-2L（SSH 2L）。SSH-2L反过来动态调节Cofilin活性和肌动蛋白聚合，以响应中性粒细胞的趋化刺激，例如fMLP。在这里，我们表明，PKD的抑制两个特定的小分子抑制剂的结果在广泛的，不受限制的Cofilin激活和强烈增加的F-肌动蛋白含量的中性粒细胞，即使在基础条件下。这种表型与通过光学拉伸分析确定的显著受损的中性粒细胞变形性相关。因此，抑制PKD损害趋化性，如中性粒细胞外渗减少所示。因此，我们证明了两者的跨内皮通道。从失血性休克创伤模型中恢复的嗜中性粒细胞样NB 4细胞和原代PMN 5显著减少。因此，PKD的抑制可能代表中性粒细胞对创伤反应的有希望的调节剂。
Neutrophils are important mediators of the innate immune defense and of the host response to a physical trauma. Because aberrant infiltration of injured sites by neutrophils was shown to cause adverse effects after trauma, we investigated how neutrophil infiltration could be modulated at the cellular level. Our data indicate that protein kinase D (PKD) is a vital regulator of neutrophil transmigration. PKD phosphorylates the Cofilin-phosphatase Slingshot-2L (SSH2L). SSH-2L in turn dynamically regulates Cofilin activity and actin polymerization in response to a chemotactic stimulus for neutrophils, for example, fMLP. Here, we show that inhibition of PKD by two specific small molecule inhibitors results in broad, unrestricted activation of Cofilin and strongly increases the F-actin content of neutrophils even under basal conditions. This phenotype correlates with a significantly impaired neutrophil deformability as determined by optical stretcher analysis. Consequently, inhibition of PKD impaired chemotaxis as shown by reduced extravasation of neutrophils. Consequently, we demonstrate that transendothelial passage of both. neutrophil-like NB4 cells and primary PMN5 recovered from a hemorrhagic shock trauma model was significantly reduced. Thus, inhibition of PKD may represent a promising modulator of the neutrophil response to trauma.