Identifying Neutrophil Specific Mechanisms for Resistance to Biologics in Ulcerative Colitis

摘要 溃疡性结肠炎（UC）是一种慢性炎症性肠病，在美国约有100万人受到影响。 美国的UC的年度医疗保健支出估计超过100亿美元，其中大多数 这些费用与昂贵的生物疗法有关。UC中最常用的两种生物制剂是 然而，Vedolizumab和阿达木单抗对这些高级治疗的疗效稳定在约30%。 因此，了解治疗耐药性的药物特异性机制的需求尚未得到满足。我们的参与者 在鼠结肠炎/结肠损伤模型中的水平患者数据和观察表明， 上皮内间隙中的中性粒细胞亚群导致持续的肠干细胞（ISC）损伤， 影响上皮隐窝微环境和生物制剂的治疗效果。因此，拟议的研究将 整合以临床患者为中心和以基本机制为中心的研究，以探索空间上不同的 具有独特遗传特征和功能的中性粒细胞群体可能决定机制特异性治疗 反应和影响粘膜损伤的解决。 在第一个目的中，使用空间分辨的单细胞和亚细胞高重数字定量mRNA和 在已经从UC患者收集的粘膜组织中的蛋白质中，我们将分析中性粒细胞、T细胞和肠 UC患者中基于空间方向的上皮（隐窝与固有层）。通过这种方法，我们将 确定预测UC患者Vedolizumab治疗应答的基因/蛋白质特征，并确定靶向 上皮中性粒细胞与隐窝和T细胞相互作用以介导对炎症反应的无应答的机制。 Vedolizumab。第二个目的将研究上皮内中性粒细胞负荷如何在功能上影响治疗性 小鼠结肠炎中结肠损伤的反应和消退。具体地，使用鼠结肠损伤/结肠炎模型， 临床相关的治疗和嗜中性粒细胞特异性遗传方法，我们将定义分子线索指导 中性粒细胞滞留在上皮内空间以及这种独特的空间定位如何影响治疗 对生物制剂（Vedolizumab、阿达木单抗和托法替尼）的应答。我们将进一步确定内部是否- 上皮中性粒细胞通过增强Vedolizumab的治疗效果， ISC损失。 因此，当前提案中概述的研究将确定对药物耐药的新机制。 生物制剂和识别分子靶点以优化/改善响应性。

Abstract Ulcerative colitis (UC) is a chronic inflammatory bowel disease affecting approximately 1 million people in the United States. Annual healthcare expenditure for UC is estimated to be more than $10 billion dollars, with most of this cost being related to expensive biologic therapies. The two most prescribed biologics in UC are vedolizumab and adalimumab, however, efficacy for these advanced therapies plateaus at approximately 30%. Thus, there is an unmet need to understand drug specific mechanisms of treatment resistance. Our participant level patient data and observations in murine colitis/colon injury models indicate that persistence of distinct neutrophil subsets in the intra-epithelial space results in ongoing intestinal stem cell (ISC) injury, negatively impacting the epithelial crypt microenvironment and treatment efficacy for biologics. Thus, proposed studies will integrate clinical patient-focused and basic mechanism-focused studies to explore the idea that spatially distinct neutrophil populations with unique genetic signatures and function may dictate mechanism specific therapeutic response and impact mucosal injury resolution. In the first Aim using spatially resolved single-cell and sub-cellular high-plex digital quantification of mRNA and protein in already collected mucosal tissue from UC patients, we will profile neutrophils, T-cells, and intestinal epithelium based on spatial orientation (crypts vs lamina propria) in UC patients. Using this approach, we will identify gene/protein signatures predictive of response to vedolizumab therapy in UC and define targetable mechanisms through which epithelial neutrophils interact with crypts and T-cells to mediate non-response to vedolizumab. Second Aim will investigate how intra-epithelial neutrophil burden functionally impacts therapeutic responses and resolution of colon injury in murine colitis. Specifically, using murine colon injury/colitis models, clinically relevant therapeutics and neutrophil-specific genetic approaches, we will define molecular cues guiding neutrophil retention in the intra-epithelial space and how this unique spatial localization impacts therapeutic response to biologics (vedolizumab, adalimumab and tofacitinib). We will further determine whether intra- epithelial neutrophils exacerbate colon injury and impede therapeutic efficacy of vedolizumab through enhanced ISC loss. As such, studies outlined in the current proposal will identify new mechanisms of therapeutic resistance to biologics and identify molecular targets to optimize/improve responsiveness.