Targeting lipid rafts for treatment of asthma

项目摘要 重度哮喘患者，尽管 可用的支气管扩张剂、皮质类固醇和Th 2靶向治疗会产生显著的发病率， 由于持续的症状以及频繁和危及生命的恶化，影响了他们的生活质量。 目前可用疗法无法控制的严重哮喘的各个方面可能显示出强烈的炎症反应， 由先天性和适应性免疫系统驱动的免疫系统，特别是在病毒加重后。 开发新的治疗策略，靶向广泛的炎症机制，而不仅仅是Th 2 和Th 1/Th 17反应，是控制严重哮喘所必需的。Raft Pharmaceuticals提出了一个新的目标， 治疗严重哮喘-支气管上皮细胞中过多和聚集的病理性脂筏， 免疫细胞在哮喘中的作用富含胆固醇的脂筏提供有序的质膜结构域， 受体、离子通道和接头分子可以结合形成功能复合物。大的脂筏 作为微生物在宿主细胞上的着陆平台以及在宿主细胞中许多炎症过程的启动所需。 支气管上皮细胞和免疫细胞。我们发现apoA-I结合蛋白（AIBP）是一种选择性地 将胆固醇消耗机制靶向炎症细胞中的病理性脂筏，而不影响 自我平衡细胞功能。后者解释了AIBP在小鼠和大鼠中的特殊安全性。在 该基金的第一阶段，使用哮喘小鼠模型，我们证明了给予生物衍生物， 从AIBP蛋白，是有效的，在急性HDM模型的哮喘小鼠，减少气道 高反应性、气道嗜酸性粒细胞增多以及Th 2细胞因子和上皮警报素的表达。模型中 在重度哮喘患者中，AIBP显著降低了肺嗜中性粒细胞增多症。对于第二阶段提案， 在生物药物开发和哮喘治疗药物的临床前评估和临床试验中 已组装，以进一步表征改进的AIBP序列RFT 1124，作为开发 可能是严重哮喘具体而言，我们计划生产和放行RFT 1124制剂以评估疗效 和毒理学研究使用cGMP兼容的过程和分析测定。RFT 1124作为 标准治疗吸入性皮质类固醇和长效β受体激动剂（ICS+LABA）的附加治疗将是 在鼻病毒（RV）感染加重哮喘的小鼠模型中进行了测试。此外，我们将使用精确 从哮喘患者和非哮喘患者死后的肺组织中切下肺切片，以测试添加剂的功效 RV感染的人气道中ICS+LABA治疗中的RFT 1124。RNAseq研究将确定 RFT 1124抑制皮质类固醇不敏感性抗炎通路和/或增强皮质类固醇敏感性 RV感染的人支气管上皮细胞中的通路。此外，鼻内给药的非GLP安全性评估 将进行RFT 1124的输送，以确定安全范围和靶器官的估计值。这些结果 将用于准备和进行与FDA的IND（B类）前会议。

PROJECT SUMMARY Patients with severe asthma who display persistent bronchoconstriction and/or reduced lung function despite available bronchodilator, corticosteroid and Th2-targeting therapy develop significant morbidity, which severely impacts their quality of life owing to persistent symptoms, as well as frequent and life-threatening exacerbations. Aspects of severe asthma currently not managed by available therapies may display a strong inflammatory component driven by the innate and adaptive immune systems, particularly following viral exacerbations. Development of new therapeutic strategies targeting a wide range of inflammatory mechanisms, not only Th2 and Th1/Th17 responses, is needed to control severe asthma. Raft Pharmaceuticals proposes a new target for treatment of severe asthma – overabundant and clustered, pathological lipid rafts in bronchial epithelial and immune cells in asthmatics. Cholesterol-rich lipid rafts provide ordered plasma membrane domains, where receptors, ion channels and adaptor molecules can associate to form functional complexes. Large lipid rafts are required as the landing pad for microbes on host cells and for initiation of many inflammatory processes in bronchial epithelial and immune cells. We discovered apoA-I binding protein (AIBP) as a molecule that selectively targets the cholesterol depletion machinery to pathologic lipid rafts in inflammatory cells, without affecting homeostatic cellular function. The latter explains an exceptional safety profile of AIBP in mice and rats. In the Phase I of this grant, using mouse models of asthma, we demonstrated that administration of a biologic derived from the AIBP protein, was effective in an acute HDM model of asthma in mice, reducing airway hyperresponsiveness, airway eosinophilia, and expression of Th2 cytokines and epithelial alarmins. In a model of severe asthma, AIBP significantly reduced pulmonary neutrophilia. For Phase II proposal, a team of experts in biologic drug development and in preclinical assessment and clinical trials of therapeutic agents in asthma has been assembled to further the characterization of an improved AIBP sequence, RFT1124, as a development candidate for severe asthma. Specifically, we plan to manufacture and release RFT1124 drug product for efficacy and toxicology studies using cGMP-compatible processes and analytical assays. The efficacy of RFT1124 as an add-on therapy to standard-of-care inhaled corticosteroids and long-acting beta-agonists (ICS+LABA) will be tested in mouse models of asthma exacerbated by rhinovirus (RV) infection. In addition, we will use precision cut lung slices from asthmatics and non-asthmatics postmortem lung tissue to test the efficacy of add-on RFT1124 in ICS+LABA treatment in RV infected human airways. RNAseq studies will establish whether RFT1124 inhibits corticosteroid insensitive anti-inflammatory pathways and/or enhances corticosteroid sensitive pathways in RV infected human bronchial epithelial cells. Further, a non-GLP safety assessment of intranasal delivery of RFT1124 will be conducted to establish an estimate of safety margin and target organs. These results will be used to prepare for and conduct pre-IND (Type B) meeting with the FDA.