Development of an Antimicrobial Cellular Therapeutic for Inhibition of Biofilm Fo

描述(由申请人提供)：慢性和感染伤口严重影响数百万美国公民的生活质量，并与并发症风险增加有关，包括截肢的破坏性后果。截至2006年，糖尿病足溃疡感染每年导致82,000人截肢，据估计，这一数字将以每年10%的速度增长。此外，在对几种类型的慢性伤口的广泛研究中，包括糖尿病足溃疡、静脉性腿部溃疡和压疮，60%的伤口被发现含有细菌生物膜。美国国立卫生研究院估计，80%的人类传染病与细菌生物膜的形成直接相关。此外，人们普遍认为细菌生物膜对抗生素治疗具有高度耐药性。越来越多的证据表明，生物膜的形成是皮肤伤口愈合的主要障碍。因此，迫切需要新的策略来破坏这些伤口中生物膜的形成。 这项快速通道SBIR翻译研究建议的具体目的是为了推动ExpressGraftEnhance组织的开发，ExpressGraftEnhance组织是Stratech公司创造的一种抗菌活性皮肤替代品，已被证明在体内烧伤感染模型(Mol Ther)中抑制多重耐药细菌的生长。2009年3月；17(3)：562-9)。Stratech已经与工业界、学术界和美国武装部队建立了一系列跨学科的合作伙伴关系，以测试ExpressGraftEnhance在防止或破坏多重耐药细菌形成生物膜方面的有效性。第一阶段的里程碑将1)证明ExpressGraftEnhance分泌的HCAP-18/LL-37对体外生物膜的形成是有效的，2)开发效力分析来监测这种生物活性，3)优化这种活的皮肤替代组织的理想生产和储存条件。第二阶段研究将：1)确定ExpressGraftEnhance组织在防止或破坏体外细菌生物被膜形成方面的有效性；2)展示ExpressGraftEnhance组织在小鼠和猪体内生物膜感染伤口模型中抑制生物膜形成的有效性；3)实施并鉴定cGMP制造工艺和效力分析，用于最终临床应用；4)证明用于产生ExpressGraftEnhance的后期传代细胞在核型上稳定、无肿瘤致瘤、不含病毒外源物质，并保持转基因的稳定性和完整性。Stratech的最终目标是将ExpressGraftEnhance皮肤替代品商业化，用于治疗因细菌定植和伤口病原体形成生物膜而难以愈合的皮肤伤口。这项提案的研究旨在产生支持ExpressGraftEnhance技术转化为人体临床试验所需的临床前数据。 近年来，细菌生物膜已成为医学界公认的伤口愈合的重要障碍，美国国立卫生研究院估计，80%的人类传染病与细菌生物膜的形成直接相关，但还没有专门针对生物膜感染的生物治疗方案被开发和上市。这项翻译快速通道SBIR提案的目标是发展一系列合作伙伴关系，以加快开发一种创新的抗菌疗法，旨在通过防止或破坏由多重耐药细菌形成的伤口生物膜来加速伤口的愈合。一种专门设计用来破坏生物膜的培养人体皮肤替代品的开发，将针对数百万患有难以愈合的皮肤伤口的患者的需求，既消除了愈合的障碍，又促进了愈合，减轻了疼痛，并降低了其他主要并发症的可能性。

DESCRIPTION (provided by applicant): Chronic and infected wounds significantly affect the quality of life for millions of US citizens and are associated with increased risk of complications including the devastating consequence of amputation. As of 2006, infections of diabetic foot ulcers resulted in 82,000 amputations each year and it has been estimated that these numbers will increase by 10% annually. Moreover, in an extensive study of several types of chronic wounds including diabetic foot ulcers, venous leg ulcers, and pressure ulcers, 60% were found to contain bacterial biofilms. The National Institutes of Health estimates that 80% of human infectious diseases are directly related to bacterial biofilm formation. Furthermore, it is widely recognized that bacterial biofilms are highly resistant to antibiotic treatment. There is a growing body of evidence indicating that biofilm formation acts as a major impediment to the healing of cutaneous wounds. Accordingly, there is an urgent need for novel strategies to disrupt biofilm formation in these wounds. The specific aims for this Fast-Track SBIR translational research proposal are designed to advance the development of ExpressGraftEnhance tissue, an antimicrobial living skin substitute created by Stratatech Corporation that has been shown to inhibit the growth of multidrug-resistant bacteria in an in vivo burn infection model (Mol Ther. 2009 Mar;17(3):562-9). Stratatech has established an interdisciplinary series of collaborative partnerships with industry, academia, and the U.S. armed forces to test ExpressGraftEnhance its effectiveness in preventing or disrupting biofilm formation by multidrug-resistant bacteria. Phase I milestones will 1) demonstrate that hCAP-18/LL-37 secreted by ExpressGraftEnhance is efficacious against biofilm formation in vitro, 2) develop potency assays to monitor this bioactivity and 3) optimize ideal production and storage conditions for this living skin substitute tissue. The Phase II study will: 1) determine the efficacy ExpressGraftEnhance tissue in preventing or disrupting bacterial biofilm formation in vitro, 2) demonstrate the efficacy of ExpressGraftEnhance tissue against biofilm formation in both murine and porcine in vivo wound models of biofilm infection, 3) implement and qualify cGMP manufacturing processes and potency assays for ultimate clinical use and 4) demonstrate that late passage cells used to create ExpressGraftEnhance are karyotypically stable, non-tumorigenic, free of viral adventitious agents, and maintain transgene stability and integrity. Stratatech's ultimate goal is to commercialize the ExpressGraftEnhance skin substitute for use in treating cutaneous wounds that are refractory to healing due to bacterial colonization and biofilm formation by wound pathogens. The studies of this proposal are designed to generate preclinical data that are required to support translation of the ExpressGraftEnhance technology into human clinical trials. Bacterial biofilms have become recently become recognized by the medical community as significant barriers to wound healing, and the National Institutes of Health estimates that 80% of human infectious diseases are directly related to bacterial biofilm formation yet no biological treatment options that specifically target biofilm infection have been developed and marketed. The goal of this translational Fast-Track SBIR proposal is to develop a series of collaborative partnerships to expedite the development of an innovative antimicrobial therapeutic aimed at accelerating the healing of wounds by preventing or disrupting wound biofilms formed by multidrug-resistant bacteria. The development of a cultured human skin substitute specifically engineered to disrupt biofilms would target the needs of the millions of patients afflicted with hard-to-heal skin wounds by both eliminating the impediment to healing while also promoting healing, reducing pain, and reducing the likelihood of other major complications.