Antifungal Dermal Templates for Wound Healing

这一阶段的SBIR的目标是研究G4Derm对该复合体的抗真菌性能 未愈合伤口中的跨王国多菌感染问题，利用逐步 接近。 要解决的问题及其规模。无法愈合的伤口对公众健康构成极大威胁， 给经济带来负担。仅在美国，慢性伤口就影响到600-800万名患者，并导致 每年超过250亿美元的医疗保健费用1，2.这些费用中的大部分与治疗有关 感染的DFU 1.多菌感染创面的复杂性，往往存在多重耐药 微生物(MDRO)，包括病原真菌，进一步促进伤口的慢性化和 抗拒治疗3-5。因此，迫切需要新的抗菌方法 广谱抗细菌和真菌活性，有效治疗慢性伤口。 这项技术将填补知识空白。对于慢性感染创面的患者，如DFUS，有效 伤口生物渗出物的处理是预防包括截肢在内的严重并发症的关键。真菌 感染是慢性伤口处理中被忽视的一个方面，新兴的研究已经开始强调 需要消除细菌和真菌病原体4.标准护理不包括抗真菌药物 治疗，病原体对常规抗真菌药物产生越来越多的抗药性，特别是在 糖尿病患者6-9。此外，仅针对混合社区中的细菌会导致真菌增加 多样性和扩张性10.此外，虽然有许多抗菌剂可用作伤口敷料材料 以细菌为靶标，它们可能会对组织再生产生毒性。例如，抗菌水凝胶可以清除 几种细菌菌株，但缺乏促进宿主细胞增殖的能力。相反地, 20-22 23、24、25 生物工程皮肤替代品可以促进更好的组织再生，但也面临着许多挑战，如 成本，有限的保质期，难以管理，在富含蛋白酶的伤口环境中不受控制的降解， 最重要的是，由于病原性定植而导致的设备故障 26，27 因为几种细菌和真菌 病原体对胶原蛋白有亲和力，并与其结合 28-30，31 ，从而将这些昂贵的产品保留到伤口 实现了无菌。因此，临床上对早期、安全和有效的治疗存在着未得到满足的需求。 感染的慢性伤口(即DFU)，消除了跨王国的多菌感染，同时 时间，导致伤口闭合和组织再生。 解决方案：我们在这里提出了一种新的自组装组织支架基质G4Derm，以(I)防止/消除 通过广谱抗菌的独特作用机制来定植感染性病原体 和抗真菌，以及(Ii)通过提供细胞附着部位促进伤口闭合和组织再生 在脚手架矩阵中。此外，G4Derm可以原位凝胶化，符合独特的伤口形状和 深度，从而实现轻松管理。 为了确定可行性，我们提出了以下具体目标： 具体目的：1)体外显示广谱抗真菌活性。里程碑：最少4个对数CFU G4Derm(主要候选者)与未经处理的对照对所有测试的真菌的减少。 具体目的2)展示G4Derm在体内消除白色念珠菌的疗效，而 促进糖尿病小鼠全层创面模型创面闭合。里程碑：(A)清理C. 感染伤口中的白念珠菌-103cfu/g组织，第1天用真菌滴度量化比较平均值 G4Derm处理的伤口组织CFU/g至未处理的对照组；(B)G4derm处理的伤口闭合 通过定量光学显微镜和组织病理学评估将各组与未处理对照组进行比较 第21天。 这些研究的结果将使第二阶段的提案能够进一步评估G4Derm对 细菌-真菌混合病原体，生物被膜的预防和治疗，GLP/GMP调节研究 在临床相关的伤口愈合的较大动物模型中获得批准和验证，同时消除 微生物感染。

The goal of this Phase I SBIR is to investigate the antifungal properties of G4Derm against the complex problem of interkingdom polymicrobial infections in non-healing wounds, utilizing a step-wise approach. Problem to be solved and its magnitude. Non-healing wounds pose a great threat to the public health and burden to the economy. In the United States alone, chronic wounds affect 6-8 million patients and result in an excess of >$25 billion annual health care expenses 1,2. The majority of these costs are related to the treatment of infected DFUs 1. The complexity of the polymicrobial wound bioburden, often harboring multi-drug resistant organisms (MDROs), including pathogenic fungi, further contributes to the chronicity of the wounds and recalcitrance to treatment 3–5. Therefore, there is an urgent need for new antimicrobial approaches that present broad-spectrum activity against both bacteria and fungi to effectively treat chronic wounds. Gap in knowledge the technology will fill. In patients with infected chronic wounds, such as DFUs, effective management of wound bioburden is crucial to prevent severe complications including amputation. Fungal infection is a neglected aspect of chronic wound management, and emerging studies have begun to highlight the need to eliminate both bacterial and fungal pathogens 4. Standard of care does not include antifungal treatment, and pathogens are increasingly developing resistance to conventional antifungals, especially in diabetic patients 6–9. Moreover, solely targeting bacteria in mixed communities results in increased fungal diversity and expansion 10. Additionally, while many antimicrobials are available as wound dressing materials targeting bacteria, they can be toxic to tissue regeneration . For example, antimicrobial hydrogels can clear several strains of bacteria but lack the ability to facilitate host cell proliferation . On the contrary, 20–22 23,24,25 bioengineered skin substitutes promote better tissue regeneration but have numerous challenges such as high costs, limited shelf life, difficult administration, uncontrolled degradation in protease-rich wound environments, and most importantly, device failure due to pathogenic colonization 26,27 because several bacterial and fungal pathogens have an affinity for, and bind to collagen 28–30,31 , thus reserving these expensive products until wound sterility is achieved. Therefore, there is an unmet clinical need for an early, safe, and effective treatment of infected chronic wounds (namely DFUs) that eliminates interkingdom polymicrobial infection and, at the same time, induces wound closure and tissue regeneration. Solution: We propose here a novel self-assembling tissue scaffolding matrix, G4Derm, to (i) prevent/eliminate colonization of infectious pathogens through a unique mechanism of action that is broad spectrum antibacterial and antifungal, and (ii) promote wound closure and tissue regeneration by providing cell attachment sites within the scaffolding matrix. Additionally, G4Derm can gel in situ and conforms to unique wound shapes and depths, thereby enabling easy administration. To establish the feasibility, we propose the following specific aims: Specific aim 1) Demonstrate broad-spectrum antifungal capacity in vitro. Milestones: minimum of 4-log CFU reduction by G4Derm (lead candidate) vs. untreated controls against all fungi tested. Specific aim 2) Demonstrate therapeutic in vivo efficacy of G4Derm to eliminate Candida albicans while promoting wound closure in a diabetic mouse full thickness wound model. Milestones: (a) clearing of C. albicans in infected wounds by < 103 CFU/g of tissue quantified by fungal titers at day 1 comparing average CFU/g of wound tissue treated by G4Derm to untreated control group; (b) wound closure in G4Derm-treated groups compared to untreated control by quantitative optical microscopic, and histopathology assessments at day 21. The results from these studies will enable a Phase II proposal to further evaluate G4Derm’s efficacy against mixed bacterial-fungal pathogens, prevention and treatment of biofilms, GLP/ GMP studies for regulatory approvals, and validation in clinically relevant larger animal models of wound healing while eliminating microbial infections.