Delivery of PAI-1-targeted intrapleural fibrinolytic therapy for empyema

脓胸是胸膜腔的细菌感染，是肺炎的严重并发症， 死亡率高达20%，其发病率在世界范围内持续增加。胸膜内纤溶 涉及递送纤溶酶原激活剂的IPFT疗法（IPFT）已被用于加速腔室的引流， 胸腔积液包括脓胸应用肺炎链球菌诱导的脓胸模型， 我们开发了一种单剂量的IPFT与纤溶酶原激活物抑制剂1（PAI-1）靶向辅助剂， 对急性脓胸治疗效果是PA单用的8倍。我们还验证了我们的能力， 纤溶潜能测定（FPA）预测脓胸患者IPFT的成功率。有趣的是 在我们的晚期脓胸模型中，IPFT的疗效降低了40 - 50%， 观察患者。这部分是由于胸膜内纤维蛋白溶解速率显著降低。到 为了减轻与PA剂量增加相关的出血并发症风险，我们建议多个 注射低剂量PAI-1靶向IPFT治疗晚期脓胸。我们的目标是找出 有效的PAI-1靶向IPFT治疗晚期脓胸。我们的假设是，成功的IPFT 晚期脓胸需要持续较长时间的纤溶活性， PAI-1。该假设将在四个具体目标中进行测试：1。最大限度地发挥IPFT在晚期- 通过靶向缓慢的纤溶速率和PAI-1，2.开发新型PAI-1 靶向肽以优化晚期脓胸中的IPFT，3.确定导致 晚期脓胸对IPFT的抵抗力增加，和4.使用纤溶潜能试验， 在治疗前确定IPFT的候选人。我们将选择给药方案，并使用两种经验证的PAI-1 测试靶向辅助剂（单克隆抗体（mAb）和对接位点肽）以减少PA剂量 在PAI-1靶向中的这些加和性机制以最大化功效，并测试PAI-1靶向的功效 使用噬菌体展示技术选择肽。我们将使用FPA分析来自II期临床试验的样本， 试验"一项评估LTI-01在感染性非引流性胸腔积液患者中的研究"（ClinicalTrials.gov; NCT 04159831）。我们将使用最先进的生化技术来分析患者的胸水和血浆 人类患者和我们独特的脓胸模型，以研究纤维蛋白溶解的分子相互作用， 晚期脓胸我们的团队拥有生物化学、肺部和技术专业知识， 完成拟议的工作。该项目解决了我们目前对发病机制的理解中的关键空白 胸膜机化，IPFT的优化和预测结果的新诊断方法的开发 的IPFT。该项目旨在改变广泛胸膜炎患者的治疗模式， 分叶状引流失败和晚期脓胸

Empyema is a bacterial infection of the pleural space, a serious complication of pneumonia that carries a mortality rate of up to 20%, the incidence of which continues to increase worldwide. Intrapleural fibrinolytic therapy (IPFT) involving the delivery of plasminogen activators has been used to expedite drainage of loculated pleural effusions, including empyema. Using a new model of Streptococcus pneumoniae-induced empyema in rabbits we developed a single-dose IPFT with a plasminogen activator inhibitor 1 (PAI-1)-targeted adjunct, which is 8-fold more effective than PA alone for treatment acute empyema. We also validated the ability of our Fibrinolytic Potential Assay (FPA) to predict the success of IPFT in patients with empyema. Interestingly, the efficacy of IPFT in our model of advanced-stage empyema is decreased by 40-50%, similar to what has been observed in patients. This is, in part, due to a significant decrease in the rate of intrapleural fibrinolysis. To mitigate the risk of bleeding complications associated with an increase in the dose of PA, we propose multiple injections of low-dose PAI-1-targeted IPFT to treat advanced-stage empyema. Our objective is to identify effective PAI-1-targeted IPFT for advanced-stage empyema. Our hypothesis is that successful IPFT in advanced-stage empyema requires fibrinolytic activity sustained over a longer period of time and neutralization of PAI-1. The hypothesis will be tested in four Specific Aims: 1. Maximize the efficacy of IPFT in advanced- stage empyema in rabbits by targeting both the slow rate of fibrinolysis and PAI-1, 2. Develop novel PAI-1 targeting peptides to optimize IPFT in advanced-stage empyema, 3. Determine the mechanisms that result in increased resistance to IPFT in advanced-stage empyema, and 4. Using the Fibrinolytic Potential Assay to identify candidates for IPFT prior to treatment. We will select a dosing schedule and use two validated PAI-1 targeting adjuncts (monoclonal antibodies (mAbs), and a docking site peptide) to decrease the dose of PA, test these mechanisms for additivity in PAI-1 targeting to maximize efficacy, and test the efficacy of PAI-1 targeting peptides selected using phage display technology. We will use the FPA to analyze samples from Phase 2 Clinical Trial “A Study to Evaluate LTI-01 in Patients with Infected, Non-draining Pleural Effusions” (ClinicalTrials.gov; NCT04159831). We will use state of the art biochemical techniques to analyze pleural fluid and plasma from human patients and our unique model of empyema to investigate the molecular interactions of fibrinolysis of advanced-stage empyema. Our team has the biochemical, pulmonary and technical expertise to successfully accomplish the proposed work. The project addresses key gaps in our current understanding of the pathogenesis of pleural organization, optimization of IPFT and development of a new diagnostic approach to predict outcomes of IPFT. This project is positioned to shift the paradigm of treatments available for patients with extensive pleural loculation, failed drainage, and advanced-stage empyema.