Antimicrobial Gene Therapy

描述：增加对常规抗生素的耐药性是人们关注的焦点。 注意替代的抗感染疗法。抗菌肽是 对微生物耐药性敏感性低的有希望的新药物 机械装置。与传统抗生素不同，抗菌肽是编码的 通过单基因，并可通过基因治疗进入感染组织 接近了。这项研究的最终目标是引入抗菌剂 将多肽基因导入移植的人类细胞，并使用这些增强的细胞来 增强宿主抵御感染的防御机制。眼下的目标是 开发一个模型系统，其中人-β-防御素-2(HBD-2)基因将被 在HBD-2阴性细胞中表达；其抗菌效果将在 体外和体内。之所以选择HBD-2基因，是因为与大多数已知的基因不同 防御素，它不需要特定于组织的处理。一种逆转录病毒 携带HBD-2基因的小鼠成功转导 成纤维细胞NIH/3T3体外分泌功能性抗菌肽的研究 此外，各种其他类型的细胞成功地转导到分泌 HBD-2已经完成。而HBD-2的体外抗菌活性 已经清楚地证明了，关于HBD-2的信息有限 在体内发挥作用。使用一种新的方法，有计划测试 分泌的HBD-2在体内具有功能。中心假设是这一点 抗菌基因治疗在增强宿主先天免疫中的作用 抗感染。一个短期目标是测试被转换的 使用小鼠模型，细胞将在体内防御感染。具体的 目的包括：1)确定时间表达和抗菌药物 HBD-2对小鼠体内移植细胞的影响。这一目标将 利用SCID小鼠生长表达HBD-2的肿瘤模型 HBD-2体内抑菌作用的定量测定。2)至 建立组织工程化创面愈合模型检测抗菌基因 在老鼠身上进行治疗。这个目标将建立一个模拟临床的模型 这一抗菌基因疗法的应用测试情况 接近。 成功完成这些目标将是建立 探索抗菌剂未来适用性的活体动物研究模型 基因疗法。拟议的方法旨在提供以下潜在好处 三种途径的临床应用：1)移植抗菌分泌物 细胞可以用于受伤的、工程的或感染的组织中，以防止和/或 对抗感染；2)这些细胞可能会减少对常规 抗生素；以及3)这些细胞可能提供长期的增强 免疫功能低下患者的天然免疫系统。

DESCRIPTION: Increasing resistance to conventional antibiotics has focused attention on alternative anti-infectious therapies. Antimicrobial peptides are promising new agents that have a low susceptibility to microbial resistance mechanisms. Unlike conventional antibiotics, antimicrobial peptides are encoded by single genes and can be introduced into infected tissues by gene therapy approaches. The ultimate goal of this study is to introduce antimicrobial peptide genes into explanted human cells, and to use these augmented cells to enhance host defense mechanisms against infection. The immediate goal is to develop a model system, in which the human-Beta-defensin-2 (HBD-2) gene will be expressed in HBD-2 negative cells; its antimicrobial effect will be tested in vitro and in vivo. The HBD-2 gene was chosen because, unlike most known defensins, it does not require tissue-specific processing. A retrovirus carrying the HBD-2 gene has permitted successful transduction of mouse fibroblast NIH/3T3 cells to secrete functional antimicrobial peptides in vitro. Additionally, successful transduction of various other cell types to secrete HBD-2 has been accomplished. While antibacterial activity of HBD-2 in vitro has been clearly demonstrated, limited information is available regarding HBD-2 function in vivo. Using a novel approach, there are plans to test whether secreted HBD-2 is functional in vivo. The central hypothesis is that this antimicrobial gene therapy is effective in enhancing host innate immunity against infection. One short-term objective is to test whether the transduced cells will defend against infection in vivo using mouse models. The Specific Aims include: 1) to determine the temporal expression and the antimicrobial effects of HBD-2 in transplanted cells in vivo in a mouse model. This Aim will utilize SCID mice to grow HBD-2 expressing tumors which model will allow quantitative measurement of the antimicrobial effect of HBD-2 in vivo. 2) To establish a tissue-engineered wound healing model to test antimicrobial gene therapy in mice. This Aim will establish a model that simulates a clinical situation for testing the application of this antimicrobial gene therapy approach. Successful completion of these Aims will be the first step in establishing in vivo animal study models to explore the future applicability of antimicrobial gene therapy. The proposed approach is intended to provide potential benefit in clinical applications in three ways: 1) transplanted antimicrobial secreting cells can be used in wounded, engineered or infected tissues to prevent and/or fight against infections; 2) these cells may reduce the need for conventional antibiotics; and 3) these cells may provide long-term augmentation of the innate immune system for immunocompromised patients.