Thr Role of Pin1 in Airway

过度气道纤维化是长期哮喘最显著的后遗症之一。慢性哮喘患者的气道经常重塑，变得增厚和弹性降低，导致尽管呼吸努力增加但气流减少。重塑气道含有产生细胞因子的免疫细胞，特别是嗜酸性粒细胞（EOS）和活化的成纤维细胞（Fb），其产生病理量的促纤维化介质和细胞外基质（ECM）。Fb ECM产生由过量的促纤维化细胞因子驱动，特别是主要由活化的EOS精心制作的TGF-β 1。TGF-β 1在Fb或EOS中引发的信号级联反应仍不完全清楚，并且尚未被有效靶向用于治疗以阻断或减弱气道重塑。我们假设Pin 1通过与近端Smads（3和6）以及P1-S-Ky和Akt相互作用并使其异构化来调节TGF-β 1信号传导。我们进一步假设肺Fb或外周血EOS中Pin 1的消融将减弱过敏原激发的啮齿动物中的气道重塑。为了验证这些假设，我们提出：目标1：确定Pint如何影响Smad 6功能。我们已经证明Pin 1结合并控制Smad 6的细胞内位置，我们将首先鉴定并突变Smad 6介导Pin 1相互作用的位点。突变的Smad 6蛋白将在Fb和EOS中表达，并将确定对Smad 6、Smad 3、Pin 1功能和定位以及TGF-β 1诱导的基因表达的功能后果。目的2：确定Pin 1和PI-3-Ky如何影响Smad 3功能和信号传导。TGF-β 1诱导Pin 1与PI-3-KY和Akt结合。此外，PI-3-K或Pin 1的抑制剂阻止Smad 3易位和ECM产生，表明共同的途径。因此，我们将定义Akt功能和与Smad 3的相互作用如何在鼠和人Fb和人EOS中由Pin 1和PI-3-K控制。目标3：测试组织和细胞选择性Pin 1 KO对急性和慢性过敏原攻击后气道重塑、EOS炎症、细胞因子表达、Fb增殖和ECM产生的影响。总之，这些研究将表征Pin 1如何调节TGF-β 1信号传导和ECM产生。

Excess airway fibrosis is among the most significant sequelae of long-term asthma. Airways in patients with chronic asthma are often remodeled, becoming thickened and less elastic, resulting in reduced airflow despite increased respiratory effort. The remodeling airway contains cytokine producing immune cells, particularly eosinophils (EOS) and activated fibroblasts (Fb) that generate pathologic amounts of profibrotic mediators and extracellular matrix (ECM), Fb ECM production is driven by excess levels of profibrotic cytokines, especially TGF-(31 that are principally elaborated by activated EOS, Despite its importance in key physiologic processes such as wound healing and tissue homeostasis, the signaling cascades elicited in Fb or EOS by TGF-(31 remain incompletely understood, and have yet to be effectively targeted for therapeutics to block or attenuate airway remodeling. We hypothesize that Pin1 modulates TGF-pi signaling by interacting with and isomerizing proximal Smads (3 and 6) as well as Pl-S-Ky and Akt, We further hypothesize that ablation of Pin1 in pulmonary Fb or peripheral blood EOS will attenuate airway remodeling in allergen challenged rodents. In order to test these hypotheses, we propose to: Aim 1: Identify how Pint influences Smad6 function. We have shown that Pin1 binds to and controls the intracellular location of Smad6, We will first identify and then mutate Smad6 sites that mediate an interaction with Pin1. Mutant Smad6 proteins will be expressed in Fb and EOS and the functional consequences on Smad6, Smad3, Pin1 function and location and TGF-(31 induced gene expression will be determined. Aim 2: Determine how Pin1 and PI-3-Ky affects Smad3 function and signaling. TGF-pi induces Pin1 to bind to both PI-3-KY and Akt, Furthermore, inhibitors of PI-3-K or Pin1 prevented Smad3 translocation and ECM production, suggesting a common pathway. Thus, we will define how Akt function and interaction with Smad3 are controlled by Pin1 and PI-3-K in both murine and human Fb and human EOS. Aim 3: To test the effects of tissue and cell selective Pin1 KO on airway remodeling, EOS inflammation, cytokine expression, Fb proliferation and ECM production following acute and chronic allergen challenge. In aggregate, these studies will characterize how Pin1 regulates TGF-pi signaling and ECM production.