Redox-based Fas signaling in allergic airway disease

描述（由申请人提供）：死亡受体Fas在肺细胞上表达，在肺细胞中它可以抑制介导不同结果的信号。我们最近发现，氧化剂过氧化氢（H2 O2）促进小鼠肺上皮细胞中Fas的聚集，H2 O2使用Fas向c-Jun-N-末端激酶（JNK）发出信号，JNK是一种关键的信号传导模块，允许细胞感知和响应压力。Fas信号转导的结果不是严格的细胞凋亡，还包括形状改变、炎症等。促生存因子NF-κ B在过敏性气道疾病小鼠的气道中以延长的方式被激活，这可以抵消Fas激活的促凋亡作用。在过敏性气道炎症期间，肺的氧化还原环境朝向促氧化状态改变，并且H2 O2存在于患有过敏性气道疾病的小鼠的肺中。因此，在该提议中待测试的假设是，H2 O2介导的患有过敏性气道疾病的小鼠的肺上皮中JNK的活化通过Fas的氧化活化促成气道高反应性（AHR）和重塑。在具体目标1中，我们将通过使用过氧化氢酶过表达小鼠和使用降低H2 O2的药理学试剂来确定H2 O2是否促进患有过敏性气道疾病的小鼠中的JNK活化、AHR和重塑。 我们还将直接施用H2 O2源，以确定H2 O2是否足以激活JNK并引发AHR，以及这是否需要功能性Fas。在具体目标2中，我们将确定Fas在患有过敏性肺病的小鼠中是否被氧化和寡聚化，以及这是否发生在气道上皮中，以及本文对H2 O2的需求。在具体目标3中，我们将通过使用全身缺乏Fas的LPR小鼠或通过产生CC 10-DN-Fas表达小鼠来确定气道上皮Fas在患有过敏性气道疾病的小鼠的气道中的JNK活化、AHR和重塑中的需求。最后，在具体目标4中，我们将通过以四环素诱导的方式在传导气道的细胞中表达显性阴性形式的JNK 1的转基因小鼠的产生来确定气道上皮JNK激活在AHR中的贡献。这些方法在确定对过敏性气道疾病的病理生理学至关重要的关键氧化剂靶点和上皮信号传导事件中至关重要。

DESCRIPTION (provided by applicant): The death receptor Fas is expressed on lung cells where it can transduce signals that mediate diverse outcomes. We recently showed that the oxidant, hydrogen peroxide (H202) promotes clustering of Fas in mouse lung epithelial cells, and that H202 uses Fas to signal to c-Jun-N-terminal kinase, (JNK), a critical signaling module that allows cells to sense and respond to stress. The outcome of Fas signaling is not strictly apoptosis, but also including shape changes, inflammation etc. The pro-survival factor, NF-kB is activated in a prolonged fashion in airways of mice with allergic airway disease, which can counteract the pro-apoptotic effect of Fas activation. During allergic airways inflammation, the redox environment of the lung is changed towards a pro-oxidant state, and H202 is present in lungs of mice with allergic airways disease. Thus, the hypothesis to be tested in this proposal is that H202- mediated activation of JNK in lung epithelium of mice with allergic airways disease contributes airways hyper-responsiveness (AHR) and remodeling, through oxidative activation of Fas. In Specific Aim 1, we will determine whether H202 promotes JNK activation, AHR, and remodeling in mice with allergic airways disease via the use of catalase over-expressing mice, and the use of pharmacologic agents that lower H202. We will also directly administer a source of H202, to determine whether H202 is sufficient to activate JNK, and elicit AHR, and whether this requires functional Fas. In Specific Aim 2, we will determine whether Fas is oxidized and oligomerized in mice with allergic lung disease, and whether this occurs in airway epithelium, and the requirement for H202 herein. In Specific Aim 3, we will determine the requirement of airway epithelial Fas in JNK activation, AHR, and remodeling in the airways of mice with allergic airway disease by using LPR mice, which lack Fas systemically, or via the creation a CC 10-DN-Fas expressing mouse. Lastly, in Specific Aim 4 we will determine the contribution of airway epithelial JNK activation in AHR through the generation of a transgenic mouse expressing a dominant negative version of JNK1 in cells of the conducting airways, in a tetracycline inducible manner. These approaches are crucial in defining critical oxidant targets and epithelial signaling events crucial to the patho-physiology of allergic airways disease.