Perforin-2: The role of a novel antimicrobial protein in diabetic foot ulcers

 描述（由申请人提供）：本申请直接响应RFA NR 15 -001中概述的几个目标。具体而言，它解决了慢性伤口细菌定植的作用;生物负载对修复过程的影响;与慢性伤口相关的机制。该项目的目的是确定抗菌分子穿孔蛋白-2（P-2）在伤口感染和伤口愈合中的作用，并优化P-2水平，以预防或更快地解决细菌伤口感染并加速愈合。伤口感染是最常见的并发症之一，其代表患有慢性不愈合伤口（例如糖尿病足溃疡（DFU））的患者的小腿截肢的主要原因之一。因此，迫切需要开发预防和治疗感染伤口的新方法，特别是由抗生素抗性微生物引起的感染伤口。我们的初步数据表明，皮肤细胞通过表达高水平的 P-2是一种抗菌蛋白，具有杀死细胞内细菌的独特特性。此外，在愈合受损的伤口中下调P-2可能有助于慢性感染和抑制愈合。我们假设P-2是伤口愈合过程所必需的，即屏障维持和恢复，并且进一步地，P-2的异常下调在感染传播和愈合抑制中起作用。为了测试这一点，我们将：评估DFU中P-2的差异表达并将P-2表达与愈合结果相关联（目的1）;确定在低和高葡萄糖浓度下生长的原代HEK和真皮成纤维细胞HDF中P-2的存在或不存在如何影响它们杀死细胞内细菌的能力，从而模拟DFU环境。(Aim 2）;鉴定P-2在急性人类伤口愈合中的作用。(Aim 3）。该项目将提供重要的数据和新知识，以了解P-2表达有助于保护免受感染的机制以及P-2在非愈合伤口（DFU）中的作用。该项目可能为开发预防感染或治疗方案的新模式提供基础，并可能同时加速伤口愈合，这两者在急性和慢性伤口感染中都具有重大的临床影响和意义。我们预计，该项目的成功完成将导致未来的研究，通过临床前和临床试验开发候选疗法。

 DESCRIPTION (provided by applicant): This application directly responds to several objectives outlined in the RFA NR15-001. Specifically, it addresses the role of bacterial colonization of chronic wounds; impact of bioburden on repair process; mechanisms associated with chronic wounds. The objective of this project is to determine the role of antimicrobial molecule, Perforin-2 (P-2) in wound infection and wound healing and to optimize P-2 levels to either prevent or more rapidly resolve bacterial wound infections and speed healing. Wound infection is one of the most frequent complications representing one of the leading causes of lower leg amputations in patients suffering from chronic non-healing wounds, such as diabetic foot ulcers (DFUs).Thus, there is an urgent need to develop new approaches that prevent and treat infected wounds, especially those caused by antibiotic- resistant microorganisms. Our preliminary data suggest that skin cells are equipped to fight infections by expressing high levels of P-2, an antimicrobial protein with unique properties to kill intracellular bacteria. Also, down-regulation of P-2 in healing impaired wounds may contribute to chronic infections and inhibition of healing. We hypothesize that P-2 is necessary for the wound healing process, i.e. barrier maintenance and restoration and further, that the aberrant down-regulation of P-2 plays a role in infection propagation and healing inhibition. To test this we will: assess differential expression f P-2 in DFUs and correlate P-2 expression with healing outcomes (Aim 1); Determine how presence or absence of P-2 in primary HEK and dermal fibroblasts HDF grown in low and high glucose concentration, thus mimicking DFU environment, will affect their ability to kill intracellular bacteria. (Aim 2); identify the role of P-2 in acute human wound healing. (Aim 3). This project will provide important data and new knowledge towards understanding mechanisms by which P-2 expression contributes to protection from infection and P-2's role in non-healing wounds (DFUs). This project may provide the basis for development of novel modes for prevention of infection or treatment regimens and potentially simultaneously accelerate wound healing, both of which would have a major clinical impact and significance in both the acute and chronic wound infections. We anticipate that successful completion of this project will lead to future studies to develop candidate therapeutics through preclinical and clinical testing.