Treating lung inflammation by targeting Siglecs

说明)： 哮喘和慢性阻塞性肺疾病(COPD)是最常见的衰弱因素 人类的肺部状况。哮喘的呼吸道炎症通常以嗜酸性粒细胞的涌入为典型，而 在慢性阻塞性肺疾病中，中性粒细胞是突出的。Siglec-8和Siglec-9存在于不重叠的细胞亚群上，具有 Siglec-8表达于人的嗜酸性粒细胞、肥大细胞和嗜碱性粒细胞，Siglec-9表达于中性粒细胞， 巨噬细胞、NK细胞和部分B、T细胞。小鼠Siglec-F和人类Siglec-8在功能上 人类Siglec-9和小鼠Siglec-E是同源基因。这些人的参与 Siglecs负性调节它们的细胞激活和存活。假设：Siglec-8和Siglec-9可以 分别通过消耗嗜酸性粒细胞和中性粒细胞来治疗肺部炎症。目标：近距离 始终与核心C和核心D协作。目的1提出利用Siglec-8/-F及其 利用现有的和新的小鼠模型研究配体在肺部炎症中的抗嗜酸性粒细胞特性 哮喘。目的2提出开发Siglec-9/-E及其配体抗中性粒细胞特性的实验 使用现有的和新的COPD和哮喘小鼠模型进行肺部炎症研究。目标3建议 开发Siglec-8/-F和Siglec-9/-E的天然内源性肺配体，在项目3和 项目4利用AIMS 1和2中使用的小鼠模型对其抗粒细胞特性进行了表征。 肺中唾液酸基转移酶和磺基转移酶在生成Siglec-F配体中的作用将通过一条途径进行探索。 上皮特异的缺失和过度表达系统。在每个目标中，我们都将测试由 项目2为他们在体内选择性靶向Siglec-8/-F和Siglec-9/-E的能力。最后，为了便于测试 这些试剂供未来人类使用，我们建议使用由Core D开发的新型人源化小鼠，用于 在哮喘和COPD模型中的测试包括a)嗜酸性粒细胞特异性Siglec-8敲入Siglec-F 在体内直接研究人类Siglec-8生物学的零遗传背景；和b)中性粒细胞特异性Siglec-9 Siglec-E零背景上的敲入小鼠和第二只携带Siglec-9 V集的转基因小鼠 与Siglec-E上的凝集素结构域外显子互换，以指导体内Siglec-9生物学研究。 相关性(请参阅说明)： 我们将利用现有最好的哮喘和慢性阻塞性肺病动物模型来测试治疗效果。 靶向嗜酸性粒细胞和中性粒细胞，通过它们的细胞表面印记在体内删除它们。其他内容 实验将确定内源性唾液酸转移酶和硫叶转移酶在肺上皮细胞形成中的作用 糖链配体用于嗜酸性粒细胞耗竭的Siglecs，并直接在小鼠中探索人类Siglec靶向。

instmctions): Asthma and chronic obstructive pulmonary diseases (COPD) are among the most common debilitating human lung conditions. Airway inflammation in asthma is often typified by an influx of eosinophils, whereas in COPD neutrophils are prominent. Siglec-8 and Siglec-9 are found on non-overlapping cell subsets, with Siglec-8 expressed on human eosinophils, mast cells and basophils, and Siglec-9 expressed on neutrophils, macrophages, NK cells and some B and T cells. Mouse Siglec-F and human Siglec-8 are functionally convergent paralogs, while human Siglec-9 and mouse Siglec-E are orthologs. Engagement of these human Siglecs negatively regulates their cellular activation and survival. HYPOTHESIS: Siglec-8 and Siglec-9 can be targeted to treat lung inflammation by depleting eosinophils and neutrophils, respectively. AIMS: In close collaboration with Core C and Core D throughout. Aim 1 proposes experiments to exploit Siglec-8/-F and its ligands for their anti-eosinophil properties in lung inflammation using existing and novel murine models of asthma. Aim 2 proposes experiments to exploit Siglec-9/-E and its ligands for their anti-neutrophil properties in lung inflammation using existing and novel murine models of COPD and asthma. Aim 3 proposes to exploit natural endogenous lung ligands for Siglec-8/-F and Siglec-9/-E, identified in Project 3 and characterized by Project 4, for their anti-granulocyte properties using mouse models utilized in Aims 1 and 2. The role of sialyl- and sulfotransferases in the lung in generating Siglec-F ligands will be explored via ainway epithelial-specific deletion and overexpression systems. In each Aim we will test nanoparticles developed by Project 2 for their ability to selectively target Siglec-8/-F and Siglec-9/-E in vivo. Finally, to facilitate testing of such agents for future human use, we propose to employ novel humanized mice, developed by Core D, for testing in the asthma and COPD models including a) an eosinophil-specific Siglec-8 knock-in on the Siglec-F null genetic background to directiy study human Siglec-8 biology in vivo; and b) a neutrophil-specific Siglec-9 knock-in mouse on the Siglec-E null background and a second transgenic mouse bearing a Siglec-9 V-set lectin domain exon swap for its counterpart on Siglec-E to directiy study Siglec-9 biology in vivo. RELEVANCE (See instructions): We will utilize the best available animal models of asthma and COPD to test the therapeutic consequences of targeting eosinophils and neutrophils for their deletion in vivo via their cell surface siglecs. Additional experiments will define the role of endogenous sialyl- and sulfoltransferases in generating lung epithelial glycan ligands for eosinophil-depleting siglecs and directly explore human siglec targeting in mice.