Genetically engineered macrophages to treat pulmonary infections

项目总结 细菌性肺炎是全世界发病率和死亡率的主要原因。增加抗菌剂 细菌性肺炎常见病原菌的耐药性需要开发新的治疗方法 战略。在这个项目中，我们将重点放在两种对公共卫生构成威胁的抗药性病原体上。伯克霍尔德氏菌 假鼻疽(BP)是东南亚肺炎(肺炎类鼻炎)的常见病原学。 澳大利亚北部。肺炎类鼻炎在22-50%的病例中是致命的，尽管接受了治疗。BP是兼职的 一种细胞内的病原体，对许多抗生素具有内在的抗药性，需要长时间的治疗。 肺炎克雷伯菌(KP)是一种细胞外病原体，是众所周知的社区-和 医疗保健相关肺炎。KP对碳青霉烯类和第三代抗生素的耐药性越来越强 头孢菌素类。由Kp耐药菌株引起的感染很难治疗，延长住院时间，而且 与高死亡率有关。BP和KP代表着迫切需要开发新的治疗方法 治疗耐药肺部感染。这个项目汇集了来自不同学科的三名研究人员 这项挑战。韦斯特博士和斯克雷特博士是肺部宿主抵抗细菌的资深研究人员。 肺部感染。他们已经建立了细菌呼吸道感染的小鼠模型，包括BP(和代用品 生物体、泰兰假单胞菌)感染和金黄色葡萄球菌。这些细菌呼吸道感染模型已被用于 调查宿主和细菌因素，评估治疗方法。克兰博士，一种癌症免疫疗法 研究人员开发了一种新颖而灵活的系统来创造基因工程巨噬细胞(GEM) 在体外或体内一个月内产生一系列分泌蛋白质。给小鼠静脉注射， 宝石在肺部高水平积聚至少4天。其他人报告说，通过呼吸道输送 巨噬细胞导致这些细胞在肺内持续定位数月。因此，静脉注射或 肺部给药可能是治疗肺部感染的一种新的、通用的治疗策略。中环 这一提议的假设是，产生促炎和/或抗菌肽的宝石和 宿主对感染部位的抵抗力可以增强对由病原体等引起的呼吸道感染的抵抗力 如BP和KP。这一假设将被检验如下：目标1.开发和测试具有增强功能的宝石 产生细胞因子白介素12(IL-12)或抗菌肽痉挛(The 小鼠与人类长春新碱的同源物)。目的2.明确定位和引起的炎症反应 体内过继转移表达IL-12或JUMP的GEM。目标3.确定被领养人是否 转移表达IL-12或JUMP的GEMS增强对由以下原因引起的急性细菌性肺炎的抵抗力 泰兰氏杆菌或肺炎克雷伯菌。这一创新项目测试了两种可能具有协同作用的新疗法 对引起肺炎的耐药但不同的病原体。此外，具有高度适应性和可调性的宝石 平台可能与其他各种肺部感染和肺部疾病非常相关。

PROJECT SUMMARY Bacterial pneumonia is a leading cause of morbidity and mortality worldwide. Increasing antimicrobial resistance among common agents of bacterial pneumonia necessitates the development of new therapeutic strategies. In this project, we focus on two resistant pathogens that are public health threats. Burkholderia pseudomallei (BP) is a common etiology of pneumonia (pneumonic melioidosis) in Southeast Asia and northern Australia. Pneumonic melioidosis is lethal in 22-50% of cases despite treatment. BP is a facultative intracellular pathogen that is inherently resistant to many antibiotics and requires prolonged courses of therapy. Klebsiella pneumoniae (KP) is an extracellular pathogen that is a well known cause of community- and healthcare-associated pneumonia. KP has become increasingly resistant to carbapenems and third generation cephalosporins. Infections caused by resistant strains of KP are difficult to treat, prolong hospital stays, and are associated with high mortality. BP and KP are representative of the urgent need to develop new therapies to treat resistant lung infections. This project brings together three investigators from distinct disciplines to tackle this challenge. Drs. West and Skerrett are established researchers in pulmonary host defense against bacterial lung infections. They have created murine models of bacterial respiratory infection including BP (and surrogate organism, B. thailandensis) infection and KP. These bacterial respiratory infection models have been used to investigate host and bacterial factors and to evaluate therapeutics. Dr. Crane, a cancer immunotherapy researcher, has developed a novel and flexible system to create genetically engineered macrophages (GEMs) to produce a range of secreted proteins over a month in vitro or in vivo. Administered intravenously to mice, GEMs accumulate at high levels in the lungs for at least 4 days. Others have reported that airway delivery of macrophages results in durable localization of these cells within the lungs for months. Thus, intravenous or pulmonary delivery of GEMs may be a novel, versatile therapeutic strategy against lung infections. The central hypothesis of this proposal is that GEMs that produce pro-inflammatory and/or antimicrobial peptides and home to the site of infection can augment host resistance to respiratory infections caused by pathogens such as BP and KP. This hypothesis will be tested as follows: Aim 1. Develop and test GEMs with enhanced bacterial killing functions that produce the cytokine interleukin 12 (IL-12) or antimicrobial peptide CRAMP (the mouse homolog of human cathelicidin). Aim 2. Define localization and the inflammatory responses induced by IL-12- or CRAMP-expressing GEMs adoptively transferred in vivo. Aim 3. Determine whether the adoptive transfer of IL-12- or CRAMP-expressing GEMs augments resistance to acute bacterial pneumonia caused by B. thailandensis or K. pneumoniae. This innovative project tests two novel and potentially synergistic therapies for resistant yet distinct pathogens causing pneumonia. Moreover, the highly adaptable and tunable GEM platform is potentially very relevant to a wide variety of other lung infections and lung diseases.