Novel role for protein kinase D in airway inflammation and antiviral immunity

呼吸道病毒是全世界发病率和死亡率的主要原因。在感染他们的目标之后 细胞，病毒是由不同的模式识别受体(PRR)感知的，这些受体启动了天然的抗病毒 免疫反应。病毒双链RNA(DsRNA)是一种有效的天然免疫刺激因子和 激活Toll样受体3(TLR3)和细胞内解旋酶RIG-I(维甲酸诱导的 基因I)和MDA5(黑色素瘤分化相关蛋白5)。双链RNA传感器 由呼吸道上皮细胞表达，并耦合到复杂的下游信号通路 启动干扰素和细胞因子基因的表达，导致呼吸道炎症和 诱导抗病毒免疫。这个R01应用程序基于我们偶然发现的 丝氨酸/苏氨酸激酶D(PKD)在先天免疫中的作用被忽视 C.有三种pkd亚型(pkd1-3)，但知之甚少 关于它们在肺中的表达或功能。使用靶向siRNA击倒和一种新的 基因敲除小鼠，我们发现PolyI：C诱导上皮细胞因子基因表达和中性粒细胞 肺的募集都依赖于PKD3。这似乎涉及一起之前未被报道的 PKD3在上皮细胞PolyI：C信号和趋化因子受体信号中的作用 中性粒细胞的转导。令人兴奋的是，我们还发现一种有效的和选择性的PKD拮抗剂 保护小鼠免受甲型流感病毒(IAV)的感染。在这份修订后的R01申请中，我们建议 三个目标：准确解释PKD如何在呼吸道上皮细胞中介导dsRNA信号转导 细胞(目标1)，使用条件删除和其他策略来解开新的中性粒细胞特定的角色 PKD3在肺部炎症中的作用(目标2)，并验证靶向PKD将减弱肺部的假说 小鼠感染流感后的炎症(目标3)。

Respiratory viruses are a major cause of morbidity and mortality worldwide. After infecting their target cells, viruses are sensed by different pattern recognition receptors (PRR’s) that initiate innate anti-viral immune responses. Viral double stranded RNA (dsRNA) is a potent stimulator of innate immunity and activates toll-like receptor 3 (TLR3) as well as the intracellular helicases RIG-I (retinoic acid-inducible gene I) and MDA5 (melanoma differentiation-associated protein 5). Double stranded RNA sensors are expressed by the airway epithelium, and couple to complex downstream signaling pathways that initiate the expression of interferons and cytokine genes, resulting in airway inflammation and induction of anti-viral immunity. This R01 application is based on our serendipitous discovery that the serine/threonine kinase protein kinase D (PKD) has a previously overlooked role in innate immune responses driven by the dsRNA polyI:C. There are three PKD isoforms (PKD1-3), but little is known about their expression or function in the lung. Using targeted siRNA knock-down and a new line of knock-out mice, we found that polyI:C-induced epithelial cytokine gene expression and neutrophil recruitment to the lung are both dependent on PKD3. This appears to involve a previously unreported role for PKD3 in polyI:C signaling in epithelial cells, as well as in chemokine receptor signal transduction in neutrophils. Excitingly, we also discovered that a potent and selective PKD antagonist protects mice from infection with influenza A virus (IAV). In this revised R01 application, we propose three Aims that will: explain exactly how PKD mediates dsRNA signal transduction in airway epithelial cells (Aim 1), use conditional deletion and other strategies to unravel a new neutrophil specific role for PKD3 in lung inflammation (Aim 2), and test the hypothesis that targeting PKD will attenuate lung inflammation after influenza infection in mice (Aim 3).