Fibroblast dysregulation promotes dermal eosinophilic/Th2 inflammation

摘要：特应性皮炎（AD）是最常见的炎症性皮肤病之一， 在成人中的患病率接近5%，并且典型地以儿科发病、尿道炎和持续性为特征。 研究表明，AD与受损的上皮屏障有关，该屏障促进对 环境抗原和II型免疫反应。尽管AD研究取得了进展， 导致持续II型免疫应答的机制仍不清楚。我们最近的出版物和 初步数据表明，真皮和皮下组织含有成纤维细胞，似乎参与建立型 II皮肤炎症反应。了解皮肤成纤维细胞调节异常如何有助于 下游事件，它们可能引发炎症性AD样病变的形成，是这一研究的重点。 提议 我们的Prel数据显示Prx 1+成纤维细胞中NF-κ B信号的失调导致CEBPb的上调， 在成纤维细胞中，CCL 11和组织嗜酸性粒细胞增多上调，随后出现类似人类的II型皮肤病变， AD.我们的小鼠模型与人类AD样病变有许多相似之处， 表皮在组织学、细胞和分子水平上。Prel Data比较了单细胞RNAseq分析， 我们的研究使用了来自人类AD病变的已发表scRNAseq数据库。来自我们模型的scRNAseq分析， 人AD显示涉及CCL 11和CEBPb成纤维细胞失调。此外，使用RNAScope，我们还 显示经验证的人AD样品含有增加数量的共表达CEBPb的真皮成纤维细胞 和CCL 11相比，也与我们的鼠模型一致。因此，我们建议 新的临床前和转化研究（目的1），以确定成纤维细胞 由CEBPb介导的失调诱导这些细胞中的炎性表型。目标2将决定 嗜酸性粒细胞浸润作为触发AD样皮肤中II型免疫应答的关键中间体的作用。目的 3将使用空间转录组学（GeoMX）和RNA测序来探索人类成纤维细胞中的等效机制 以及AD标本和使用抑制剂作为AD潜在治疗的转化研究。我们预计 建议的研究沿着最近的文献报告，以促进理解的范式转变 AD发病机制与成纤维细胞失调有关，有助于开发新的治疗方法 可以预防AD发展的干预措施。

Abstract: Atopic dermatitis (AD) is one of the most common inflammatory skin diseases with an estimated prevalence approaching 5% in adults and is typically characterized by pediatric onset, pruritis and persistance. Research has indicated that AD is associated with an impaired epithelial barrier that promotes sensitization to environmental antigens and a type II immune response. Despite advances in AD research, the causative mechanism(s) leading to the persistent type II immune response remain unclear. Our recent publication and Prel Data indicate that the dermis and subcutis contain fibroblasts that appear to be involved in establishing type II inflammatory reactions in skin. Understanding how dysregulation of skin fibroblasts contributes to downstream events that they may intitiate formation of inflammatory AD-like lesions is the focus of this proposal. Our Prel Data show that dysregulation of NF-kB signaling in Prx1+ fibroblasts leads to upregulation of CEBPb in fibroblasts, upregulation of CCL11 and tissue eosinophilia followed by type II skin lesions resembling human AD. Our mouse model shares many similarities with human AD-like lesions involving both the dermis and epidermis at the histologic, cellular and molecular levels. Prel Data compares single cell RNAseq analysis from our study with published scRNAseq databases from human AD lesions. scRNAseq analysis from our model and human AD show fibroblast dysregulation involving CCL11 and CEBPb. Moreover, using RNAScope we have also shown that validated human AD samples contain increased numbers of dermal fibroblasts co-expressing CEBPb and CCL11 compared to matched control human skin, also consistent with our murine model. Thus, we propose novel preclinical and translational studies (Aim 1) to define molecular mechanisms by which fibroblast dysregulation mediated by CEBPb induces an inflammatory phenotype in these cells. Aim 2 will determine the role of eosinophil infiltration as a key intermediate for triggering type II immune response in AD-like skin. Aim 3 will use spatial transcriptomics (GeoMX) and RNA seq to explore equivalent mechanisms in human fibroblasts and AD specimens and translational studies using inhibitors as potential treatments for AD. We expect the proposed studies along with recent reports in the literature to contribute to a paradigm shift in understanding AD pathogenesis regarding fibroblast dysregulation and contribute to development of new therapeutic interventions that may prevent the development of AD.