Leveraging immune-fibroblast interactions for biomaterial induced skin regeneration

项目总结 再生天然皮肤元素-毛囊、汗腺和脂肪组织-是一个高度重视的问题 创面愈合后转归。虽然，原则上，成年小鼠的非常大的皮肤伤口可以自发地 再生新的毛囊和新的脂肪细胞，通常研究小鼠的小伤口和临床伤口 在人类中，愈合时会出现一种远不那么令人满意的纤维性疤痕。如果以及如何指示成人皮肤伤口可以替换 疤痕愈合的自然倾向与天然皮肤成分的再生仍不清楚。 这一应用的灵感来自一个偶然的发现，即在我们的新生物材料中添加一种抗原 微孔退火颗粒(MAP)水凝胶，当加入到 正常情况下小鼠皮肤创口为纤维性。这种免疫调节的MAP凝胶提供伤口常驻免疫。 具有触发适应性免疫反应的分子的细胞，以增强巨噬细胞的反应。 此外，我们对自然再生的超大面积皮肤创伤模型的研究表明，巨噬细胞-成纤维细胞 相互作用是刺激新毛囊再生的关键。 通过综合生物工程、生物信息学和实验方法，这一应用程序将 专注于测试我们的新假设，即通过设计MAP凝胶来具有特定的免疫触发、相互作用 创面中T细胞、巨噬细胞和成纤维细胞之间可以转化正常的促纤维化愈合反应 转化为非常理想的再生反应。拟议研究的第一个目标是机械地建立 MAP形成所需的淋巴细胞和巨噬细胞亚群及分子信号通路 我们已经创造了诱导毛囊再生的产品。这将使用生物信息学分析来实现 单细胞分辨率的转录组学、蛋白质组学和功能图谱。确认为体内功能丧失/ 转基因小鼠的研究缺乏关键的免疫途径或细胞MAP凝胶。第二个目标是设计新的 旨在最大限度地诱导T细胞和巨噬细胞促再生的免疫调节MAP凝胶类型 在使用高通量体外检测的同时最大限度地减少促纤维化信号。第三个目标是确定 MAP凝胶诱导的免疫信号如何增强创伤成纤维细胞的谱系可塑性是 新的头发再生。这将通过对单细胞转录的高级生物信息学分析来实现 伤口免疫细胞和成纤维细胞的数据和功能得失研究。 研究的前提是基于新接受的出版和广泛的初步数据。建议数 研究具有重要意义，因为它们将建立新的免疫细胞驱动的增强成纤维细胞的机制 成人创面中天然皮肤成分的可塑性和激活胚胎样再生。建议数 研究具有创新性，因为它们将建立新型的免疫调节生物材料，以及新的 生物材料在成人组织中触发再生反应的范例。在未来，这项研究的结果 将推动下一代免疫调节伤口生物材料的开发，具有潜在的临床应用价值。

PROJECT SUMMARY Regeneration of native skin elements – hair follicles, sweat glands and adipose tissue, is a highly thought after outcome of wound healing. While, in principle, very large skin wounds in adult mice can spontaneously regenerate new hair follicles and new adipocytes, commonly studied small wounds in mice and clinical wounds in humans heal with a far less desirable fibrotic scarring. If and how adult skin wounds can be directed to replace the natural tendency for healing with a scar with regeneration of native skin elements remains unknown. This application is inspired by a serendipitous discovery that adding an antigen to our novel biomaterial, the Microporous Annealed Particle (MAP) hydrogel, can induce regeneration of new hair follicles when added into normally fibrotic small mouse skin wounds. This immunomodulatory MAP gel provides wound-resident immune cells with the molecular triggers that elicit an adaptive immune response to enhance macrophage responses. Further, our studies on naturally regenerating very large skin wound model show that macrophage-fibroblast interactions are essential for stimulating new hair follicle regeneration. Through an integrated bioengineering, bioinformatic and experimental approach, this application will focus on testing our new hypothesis that by engineering MAP gels to have specific immune triggers, interactions between T-cells, macrophages, and fibroblasts in the wound can transform normally profibrotic healing response into highly desirable regenerative response. The first aim of the proposed research is to mechanistically establish the lymphocyte and macrophage subsets and the molecular signaling pathways required for MAP formulations we have created to elicit hair follicle regeneration. This will be achieved using bioinformatic analyses of transcriptomics, proteomic, and functional profiling at single-cell resolution. confirmed with in vivo loss of function/ transgenic mouse studies lacking key immune pathways or cells MAP gels. The second aim is to engineer new types of immunomodulatory MAP gels designed to maximally induce T-cells and macrophage pro-regenerative signals while minimizing pro-fibrotic signals using a high-throughput in vitro assay. The third aim is to determine how MAP gel-induced immune signals enhance lineage plasticity of wound fibroblasts that is prerequisite for new hair regeneration. This will be achieved via an advanced bioinformatic analysis on single-cell transcriptomic data and functional gain- and loss-of-function studies on wound immune cells and fibroblasts. The study premise is based on newly accepted-for-publication and extensive preliminary data. The proposed studies are significant because they will establish new immune cell-driven mechanism for enhancing fibroblast plasticity and activating embryonic-like regeneration of native skin elements in adult wounds. The proposed studies are innovative because they will establish new types of immune-modulating biomaterials, and new paradigm of biomaterial-triggered regenerative response in adult tissues. In the future, the results of this study will drive the development of next-generation immune-modulating wound biomaterials for potential clinical use.