Nanoparticle Targeting of Neutrophil Subpopulations in Inflammatory Lung Injury

项目摘要/摘要 ARDS是由于免疫反应严重失调所致，导致肺血管损伤和富含蛋白质 浮肿。中性粒细胞(PMN)过度激活是导致肺损伤的主要原因。处于实验阶段 脓毒症和脓毒症患者，一些中性粒细胞被强烈激活并隔离在肺部，而另一些则通过 通过肺微血管畅通无阻，并发挥必要的宿主防御细胞的功能。之前的研究结果 提示PMN可能以不同的亚集形式存在，并处于不同的激活阶段。这一概念 PMN的异质性增加了激活的PMN的子集可能导致适应不良的可能性 炎症反应，并对肺损伤负责。我们发现PMN的一个子集特别是 内化的100纳米白蛋白纳米粒(ANP)。正如我们的支持数据显示的那样，PMN的数量 在小鼠实验性脓毒症中显著增加，而且它们被证明是发育所必需的 炎症性肺损伤。我们还将药物偶联到ANP上，使其精确地输送到这些PMN中。这些 结果提出了几个基本问题：PMN人群的性质是什么？有没有相关的 人类中的人口？它们的功能是什么？它们的起源是什么？心钠素的作用机制是什么 内化？这些细胞是否介导了肺损伤，ANP能否将药物输送到PMN群体中以逆转 病程是怎样的？我们将通过描述PMN的功能来解决这些问题 CD11bHighCD16+CD45HighANP高PMN子集与对照CD11bHighCD16+CD45HighANPlow PMN相反 在介导炎性肺损伤方面(目标1)。在这里，我们将测试ANPHigh PMN是 中性粒细胞在功能上与中性粒细胞不同，前者在介导肺损伤中起关键作用。接下来，我们将 确定不同中性粒细胞亚群中的差异β-2整合素信号及其在 调解肺损伤(目标2)。在这里，我们将检验β2整合素和下游信号的假设 与ANPlow PMN相比，ANP高PMN中通路过度激活，差异PMN信号转导 需要炎症性肺损伤。最后，我们将定义起源、命运和表型异质性 中性粒细胞介导肺损伤(目标3)。在这里，RNA-Seq图谱到目前为止已经揭示了不同的趋化因子 受体作为肺内ANP高PMN的标志，我们将利用这一信息来分离这个亚群，以进一步 描述它们的特征，并评估它们在介导肺损伤中的功能作用。我们还将定义时间- 炎性激活过程中ANPHigh与ANPlow PMN的依赖转录图谱和网络 评估它们的不同性质。因此，共同的研究将不仅定义一个人群有毒的伤害促进 但也有望找到新的治疗靶点来逆转炎性肺病的进程 受伤。

PROJECT SUMMARY / ABSTRACT ARDS results from a severely dysregulated immune response that leads to lung vascular injury and protein-rich edema. Excessive activation of neutrophils (PMNs) is a primary cause of the lung damage. In experimental sepsis and septic patients, some PMNs are intensely activated and sequestered in lungs while others pass through the lung microvasculature unimpeded and function as essential host-defense cells. Previous findings suggest that PMNs might exist as various subsets and in different stages of activation. The concept of heterogeneity of PMNs raises the possibility that a subset of activated PMNs may contribute to a maladaptive inflammatory response and be responsible for lung injury. We found that a subset of PMNs specifically internalized 100 nm albumin nanoparticles (ANPs). As our Supporting Data show this population of PMNs increased significantly in experimental sepsis in mice and they were shown to be essential for the development of inflammatory lung injury. We also conjugated drugs to ANP for their precise delivery into these PMNs. These results raise several fundamental questions: What is the nature of this PMN population? Is there a related population in humans? What is their function and what is their origin? What is the mechanism of ANP internalization? Do these cells mediate lung injury and can ANP deliver drugs into this PMN population to reverse the course of the disease? We will address these PMNs by characterizing the function of CD11bhighCD16+CD45highANPhigh PMN subset as opposed to control CD11bhighCD16+CD45highANPlow PMNs in mediating inflammatory lung injury (Aim 1). Here we will test the hypothesis that ANPhigh PMNs are functionally distinct from ANPlow PMNs and that the former are crucial in mediating lung injury. Next, we will determine differential β2 integrin signaling in the distinct PMN sub-populations and their role in mediating lung injury (Aim 2). Here we will test the hypothesis that β2 integrins and downstream signaling pathway are hyper-activated in ANPhigh PMNs compared to ANPlow PMNs and differential PMN signaling is required inflammatory lung injury. Finally, we will define the origin, fate, and phenotypic heterogeneity of PMNs mediating lung injury (Aim 3). Here, RNA-Seq profiling has thus far revealed distinct chemokine receptors as markers of ANPhigh PMNs in lungs, and we will use this information to isolate this subset to further characterize them and assess their functional role in mediating lung injury. We will also define the time- dependent transcriptomic profiles and networks of ANPhigh vs. ANPlow PMNs during inflammatory activation to assess their differential properties. Thus, together studies will not only define a population toxic injury-promoting population of PMN but also hopefully identify new therapeutic targets to reverse the course of inflammatory lung injury.