Keratinocyte Integrin Crosstalk During Wound Healing.

项目总结 表皮角质形成细胞通过修复表皮屏障和分泌，对正常伤口愈合至关重要。 旁分泌因子控制不同的过程，包括伤口血管生成和肌成纤维细胞功能。在……里面 在致病环境下，表皮功能受损会导致慢性不足(如糖尿病溃疡)或过度- 愈合旺盛(例如，增生性疤痕)。我们的长期目标是通过以下方式开发治疗范例 哪些整合素可以被操纵来调节致病角质形成细胞的功能。虽然它已经建立得很好了 整合素调节增殖、迁移和生长因子信号，它们在协调创伤中的作用 角质形成细胞的功能仍然是个谜。此外，尽管正常和创伤角质形成细胞表达整合素 91，在体内，经解释整合素91丢失，混淆了先前研究中的观察结果 体外培养。使用基因定义的、病毒转导的表达整合素31和/或91的角质形成细胞 不同的组合，我们在上一个项目期发现，91对 由31调控的创伤细胞功能和基因表达，包括促进 调节基底膜组装的内皮细胞功能和自分泌信号。从基因上使用 定义了我们衍生的在表皮中表达31和/或91不同组合的小鼠，我们 此外，还发现从表皮中删除91可以促进伤口血管生成，并增强层粘连蛋白2 处理在再生、损伤后的表皮基底膜。根据我们最近发布的 研究和新的基础数据，我们现在假设91交叉抑制31依赖 角质形成细胞通过抑制新的31-FAK-YAP/TAZ信号轴发挥功能。我们进一步假设 这个信号轴控制着促进角质形成细胞创伤功能的基因表达程序， 包括对内皮细胞和成纤维细胞的旁分泌刺激和基底膜的自分泌调节 膜组件。这一假设将在三个目标上进行验证，使用共同文化模型的组合， QPCR阵列、蛋白质组学、PAC-seq信使核糖核酸分析、细胞生物学和已定义的小鼠遗传模型。在 在这个项目期结束时，我们将在第一个项目期开发的基础上进行阐述 角质形成细胞中整合素信号下游的复杂信号网络调控旁分泌和 正常伤口中的自分泌信号。我们还将确定这些整合素信号通路是如何 在血管生成和其他伤口过程持续存在的表皮肿瘤中发生改变。通过这样做，我们将 为新的整合素靶向疗法调节角质形成细胞功能和伤口奠定了基础 结果。

PROJECT SUMMARY Epidermal keratinocytes are vital to normal wound healing by restoring the epidermal barrier and secreting paracrine factors that govern diverse processes including wound angiogenesis and myofibroblast function. In pathogenic settings, impaired epidermal function results in chronically insufficient (e.g., diabetic ulcers) or over- exuberant healing (e.g., hypertrophic scars). Our long-term goal is to develop therapeutic paradigms through which integrins can be manipulated to modulate pathogenic keratinocyte function. While it is well established that integrins regulate proliferation, migration and growth factor signaling, their roles in orchestrating wound keratinocyte functions remain enigmatic. Moreover, while normal and wound keratinocytes express integrin 91, in vivo, upon explanation integrin 91 is lost, confounding observations made in previous studies, in vitro. Using genetically defined, virally transduced keratinocytes that express integrins 31 and/or 91 in different combinations, we discovered in the last project period that 91 exerts a cross-suppressive effect on wound cell function and gene expression that is governed by 31, including paracrine signals that promote endothelial cell function and autocrine signals that regulate basement membrane assembly. Using genetically defined mice that we have derived expressing different combinations of 31 and/or 91 in the epidermis, we also found that deletion of 91 from epidermis promoted wound angiogenesis and enhanced laminin 2 processing in the regenerating, epidermal basement membrane after injury. Based on our recently published studies and new foundation data, we now hypothesize that 91 cross-suppresses 31-dependent keratinocyte functions through inhibition of a novel 31-FAK-YAP/TAZ signaling axis. We further hypothesize that this signaling axis controls a gene expression program that promotes keratinocyte wound functions, including paracrine stimulation of endothelial cells and fibroblasts and autocrine regulation of basement membrane assembly. This hypothesis will be tested in three Aims using a combination of co-culture models, qPCR arrays, proteomics, PAC-seq mRNA analysis, cell biology, and defined genetic mouse models. At the end of this project period, we will have built on the foundation developed in the first project period to elucidate the complex signaling network downstream of integrin signaling in keratinocytes that governs paracrine and autocrine signaling in normal wounds. We will also have determined how these integrin signaling pathways are altered in epidermal tumors in which angiogenesis and other wound processes persist. In doing so, we will have developed the basis for novel integrin targeting therapeutics to modulate keratinocyte function and wound outcome.