Identification of extracellular matrix-derived biomarkers and targets in dystrophic epidermolysis bullosa

营养不良性大疱性表皮松解症（DEB）是一种由胶原蛋白VII缺乏引起的遗传性皮肤起泡疾病。该疾病最严重的形式还具有形成愈合缓慢的伤口和进行性软组织纤维化的特征，这大大增加了疾病的发病率。此外，由损伤和纤维化的皮肤微环境驱动的皮肤鳞状细胞癌是严重DEB患者死亡的主要原因。迫切需要更好地治疗该疾病，但对治疗方法、疗效和安全性的担忧阻碍了因果疗法的发展。另一种方法是针对皮肤脆弱后发生的病理表现。这些表现的发展与转录组、蛋白质组和降解组的特定变化有关，这些变化可以作为疾病进展和严重程度的生物标志物。然而，为了改善症状缓解治疗和识别强大的生物标志物，需要增加对这些表现的建立和进展所涉及的机制的了解。通过对纤维化真皮细胞外基质（ECM）的回顾性详细分析，我们的方法将描述其形成过程，重点关注其主要成分，纤维性胶原及其伴侣。生理性皮肤ECM的建立是通过表皮和真皮层的调节和协调活动，导致胶原纤维形成和ECM组织，其生物力学特性优化以支持皮肤功能。在纤维化中，这些过程被破坏。在本提案中，我们计划全面分析纤维化ECM，以表征DEB中受影响最严重的过程，并确定(i)在临床试验中改善DEB疾病阶段监测的新型生物标志物和（ii）概念上新颖的循证治疗方法来治疗DEB。我们的联盟汇集了德国合作伙伴（弗莱堡大学皮肤科）和法国合作伙伴（里昂大学LBTI-CNRS），他们在DEB疾病和ECM生物学领域拥有国际知名的专业知识。该项目将分为4个任务，具体目标如下：1)表征DEB皮肤的真皮胶原基质；2)分析DEB中真皮-表皮通讯改变的影响；3)评价ECM重塑蛋白酶在DEB纤维化中的作用；4)在患者样本中验证在先前任务中确定的生物标志物的临床相关性。总之，这些研究将提供必要的信息，以了解导致DEB严重程度的主要因素，并将使我们在验证新的生物标志物和治疗靶点方面取得重大进展。预计我们的建议将对其他类型的炎症和纤维化驱动的病理性伤口的理解和管理产生重大的衍生效应。

Dystrophic epidermolysis bullosa (DEB) is a genetic skin blistering disorder caused by collagen VII deficiency. The most severe forms of the disease are also characterized by formation of slow healing wounds and progressive soft tissue fibrosis, which significantly contribute to disease morbidity. Furthermore, cutaneous squamous cell carcinoma driven by the injured and fibrotic dermal microenvironment is the major cause of death in severe DEB. Better treatment of the disease is urgently needed but development of causal therapies is hampered by concerns surrounding delivery, efficacy and safety. An alternative is to target the pathological manifestations occurring subsequent to skin fragility. Development of such manifestations is linked to specifc changes in the transcriptome, proteome and degradome, which can be employed as biomarkers of disease progression and severity. However, for both improved symptom-relief therapy and identification of robust biomarkers, an increased knowledge of the mechanisms involved in the establishment and progression of such manifestations is needed. By retrospective detailed analysis of the fibrotic dermal extracellular matrix (ECM), our approach will be to delineate the processes involved in its buildup with a focus on its major components, the fibrillar collagens and their partners. Establishment of a physiological dermal ECM occurs through regulated and coordinated activity of the epidermis and dermis, leading to collagen fibrillogenesis and ECM organization with biomechanical properties optimized to support skin function. In fibrosis, these processes are disrupted. In this proposal, we plan to comprehensively analyze the fibrotic ECM in order to characterize the most severely affected processes in DEB and to identify (i) novel biomarkers for improved monitoring of DEB disease stages during clinical trials and (ii) conceptually novel evidence-based therapeutic approaches to treat DEB.Our consortium brings together a German partner (Dept. Dermatology, University of Freiburg) and a French partner (LBTI-CNRS, University of Lyon) with internationally-renowned expertise in the fields of DEB disease and ECM biology. The project will be organized in 4 tasks with the following specific goals: 1) to characterize the dermal collagen matrix in DEB skin; 2) to analyze the influence of altered dermal-epidermal communication in DEB; 3) to evaluate the role of ECM remodeling proteinases in DEB fibrosis; 4) to validate, in patient samples, the clinical relevance of biomarkers identified in previous tasks.Together, these studies will provide essential information to understand the main factors contributing to DEB severity and will allow us to make significant progress towards the validation of both novel biomarkers and therapeutic targets. It is also expected that our proposal will have significant spin-off effects for the understanding and management of other types of inflammation- and fibrosis-driven pathological wounds.