Development of PolyAspirin Particles for Therapeutic Intervention in ALI/ARDS via the Passive Restraint of Neutrophil Function

摘要 这项工作的中心目标是开发静脉（IV）注射的聚阿司匹林（Poly-A）颗粒， 中性粒细胞功能的被动抑制用于急性肺损伤（ALI）的治疗干预。阿里是一个快速 以肺内皮和上皮屏障破坏为特征的进展性炎性疾病， 导致液体在肺气道中积聚并因此损害肺功能。急性肺损伤 呼吸窘迫综合征（ARDS）是一种更严重的ALI，在美国每年影响约20万患者 目前，死亡率约为40- 60%。到目前为止，还没有一种有效的药理学策略， 降低ALI/ARDS的死亡率，这可能是由于许多复杂的病理事件， 导致这种疾病。因此，这种疾病的主要治疗方法是使用机械呼吸机进行血液净化。 氧合和CO2清除，以使受损的肺愈合，但这可能导致对肺的进一步损害 如果不小心使用。中性粒细胞已被确定为炎症的主要肇事者， ALI/ARDS，它们过度迁移到肺中导致肺泡毛细血管破坏 导致肺水肿的屏障。事实上，疾病的严重程度与中性粒细胞的浓度相关 在肺部气道。因此，阻止不需要的中性粒细胞积聚的破坏性潜力一直是一种有效的方法。 是发展ALI/ARDS治疗的主要焦点。然而，先前开发药物的尝试， 阻断嗜中性粒细胞信号传导/粘附分子由于存在大量冗余， 在炎症反应级联中的作用在这里，我们建议合理设计血管靶向颗粒（VTP） 其与中性粒细胞物理相互作用以被动且快速地阻断中性粒细胞积聚到发炎组织中 在ALI/ARDS。我们的主要假设是VTP通过物理作用与血液中的中性粒细胞相互作用， 相互作用和竞争血管结合空间，改变中性粒细胞粘附到血管壁， 严重影响它们迁移到患病组织中。在这个提议中，我们利用这些阻塞的相互作用 通过三个目标开发生物可降解、生物相容性良好的VTP作为治疗ALI/ARDS的有效方法。 首先，我们将制作一个基于聚阿司匹林的VTP系统，并评估其颗粒尺寸和表面的影响 它们在体外特异性阻断中性粒细胞粘附到血管壁的能力的特征。二是 通过活体显微镜成像观察基于聚阿司匹林的VTP与血管壁的粘附 以及它们在小鼠炎症肠系膜组织中体内对中性粒细胞粘附的阻断。第三，我们将评估 聚阿司匹林颗粒在患有细菌诱导的ALI/ARDS的小鼠中的治疗功能， 人类疾病的真实模型。总的来说，从这些目标中获得的知识有望推动 新型颗粒抗炎疗法在治疗ALI/ARDS中的未来发展。的 建议VTP对中性粒细胞的直接作用，而不是阻断粘附或信号分子， 确保无论ALI/ARDS的主要原因如何，所建议的系统都可以发挥作用。

ABSTRACT The central goal of this work is to develop intravenously (IV)-injected Poly-Aspirin (Poly-A) particles as passive restraints of neutrophil function for therapeutic intervention in Acute Lung Injury (ALI). ALI is a rapidly progressing inflammatory disease characterized by the disruption of the lung endothelial and epithelial barriers, leading to accumulation of fluids in the lung airway and hence impaired lung function. ALI together with acute respiratory distress syndrome (ARDS), a more severe form of ALI, affects ~200,000 patients per year in the US currently, with a mortality rate of ~40-60%. To date, there is no one pharmacological strategy effective towards reducing the mortality in ALI/ARDS, likely due to the numerous and complex set of pathological events that can lead to this disease. Thus, the primary treatment for this disease is the use of a mechanical ventilator for blood oxygenation and CO2 removal to allow the damaged lung to heal, but this can lead to further damage to the lung if not employed with care. Neutrophils have been identified as the primary perpetrator of inflammation in ALI/ARDS, where their excessive migration into the lungs contributes to the destruction of the alveolar-capillary barrier that leads to edema in the lungs. Indeed, disease severity correlates with the concentration of neutrophils in the lung airways. Thus, halting the destructive potential of unwanted neutrophil accumulation has been a principal focus for the development of ALI/ARDS treatment. However, prior attempts at developing drugs that block neutrophil signaling/adhesion molecules have met with limited success due to the numerous redundancies in the inflammatory response cascade. Here, we propose to rationally design vascular-targeted particles (VTPs) that physically interact with neutrophils to passively and rapidly block neutrophil accumulation into inflamed tissue in ALI/ARDS. Our main hypothesis is that VTPs interact with neutrophils in the bloodstream, via physical interaction and competition for vascular binding space, to alter neutrophil adhesion to the vessel wall, which critically impacts their migration into the diseased tissue. In this proposal, we harness these blocking interactions to develop a biodegradable, biocompatible VTPs as an effective treatment for ALI/ARDS through three Aims. First, we will fabricate a PolyAspirin-based VTP system and evaluate the impact of their particle size and surface characteristics on their ability to specifically block neutrophil adhesion to the vessel wall in vitro. Second, we will visualize, via intravital microscopy imaging, the adhesion of the PolyAspirin-based VTPs to the blood vessel wall and their blocking of neutrophil adhesion in vivo in inflamed mesentery tissue in mice. Thirdly, we will evaluate the therapeutic functionality of PolyAspirin particles in mice with bacteria-induced ALI/ARDS, representing a realistic model of the human disease. Overall, the knowledge gained from these Aims is expected to drive the future development of novel particle-based anti-inflammatory therapeutics in the treatment of ALI/ARDS. The proposed direct action of VTPs on neutrophils, rather than blocking of adhesion or signaling molecules, will ensure that the proposed system can function irrespective of the primary cause of ALI/ARDS.