Repairing the Kidney Endothelium via Targeted Extracellular Matrix Modifiers

项目摘要 肾脏微血管是炎症性疾病和缺氧性损伤的交汇点， 内皮失调和潜在的细胞外基质（ECM）恶化。所有这些 这些变化导致进行性肾功能障碍并最终衰竭。微血管的调节作用 一般来说-特别是肾脏的微脉管系统-延伸超过其血液携带能力， 对全身内环境稳定有着全球性的影响。尽管发展了肾血管病变的动物模型， 功能障碍，这是科学研究的重要组成部分，治疗工具的翻译， 从动物到人类的知识受到疾病转基因模型之间不一致联系的限制 和人体血管生理学。对肾血管微环境的新的科学认识， ECM组成和其中内皮细胞的相互依赖性提供了离体开发的信息。 肾脏微血管模型。然而，生物工程系统往往过于简化复杂， 肾内皮生物学的相互依赖性以及与周细胞和基质的必要串扰 微环境。尽管在光刻和增材制造方面取得了新的进展， 体内微脉管系统内通常存在的鳞片不能被复制 在体外重现肾微环境。为了解决这个问题，我们的多学科团队开发了 一种生物复制的肾脏微血管系统，模拟正常肾脏的规模、ECM组成和流体力学。 肾科学研究的基础是这个血管化的支架系统， 我们公开的数据证明了通畅的和可灌注的动脉和静脉循环（Caralt等人，Am J Transplant，2015），并严格控制流体动力学（Uzarski等人，组织工程C部分方法，2015）， 一起形成生物复制的“试验台”。该平台提供了操纵ECM的独特机会 微环境与新技术，解锁细胞功能。为了进行这样的调查，我们 开发了靶向ECM修饰剂（TEM），一种新的生物材料输送系统，基于我们初步的 和已发表的数据（Jiang等人，Biomacromolecules，2016）证明了有区别地靶向和 将生物活性剂穿梭于特定ECM亚组分。我们的假设是内皮修复导致 血管修复可以通过将生物活性材料递送到基质中来控制 ECM界面处的内皮细胞。我们的调查得到了数据的支持，显示了7倍的增长富集 与溶液中游离递送的可溶性因子相比， 维持离体血管内皮28天，其中在其不存在时没有血管内皮发育。这 由生物工程，纳米技术， 肽化学和肾脏病学，以定制离体肾血管系统，并使用一组TEM来开发测试 研究疾病和治疗的平台，以修复肾血管损伤和逆转肾脏疾病。

PROJECT SUMMARY The renal microvasculature is the convergence point for inflammatory disorders and hypoxic injury that cause endothelial dysregulation and deterioration of the underlying extracellular matrix (ECM). Together, these changes lead to progressive kidney dysfunction and ultimately failure. The regulatory role of the microvasculature in general—and in particular the microvasculature of the kidney—extends beyond its blood carrying capacity, with global implications to total-body homeostasis. Despite development of animal models of renal vascular dysfunction, which are important components of scientific research, translation of therapeutic tools and knowledge from animals to humans is limited by inconsistent linkages between transgenic models of disease and human vascular physiology. New scientific understanding of the renal vasculature microenvironment, its ECM composition, and the interdependency of endothelial cells within it provide information to develop ex vivo models of renal microvasculature. However, bioengineered systems oftentimes oversimplify the complex, interdependent nature of renal endothelial biology and the necessary cross-talk with pericytes and stroma within the microenvironment. Despite new advances in photolithography and additive manufacturing, the tiny length scales typically found within the in vivo microvasculature cannot be replicated and thus fail to adequately recapitulate the renal microenvironment ex vivo. To address this deficiency, our multidisciplinary team developed a bio-replicative renal microvasculature that mimics the scale, ECM make-up and fluid mechanics of the normal kidney. The foundation for the scientific investigation is this vascularized scaffolding system that is supported by our published data demonstrating patent and perfusable arterial and venous circulation (Caralt et al., Am J Transplant, 2015) with strict control of hydrodynamics (Uzarski, et al., Tissue Eng Part C Methods, 2015) that together result in a bio-replicative ‘test rig’. This platform provides unique opportunities to manipulate the ECM microenvironment with new technologies that unlock cellular function. To enable such an investigation, we developed Targetable ECM Modifiers (TEMs), a new biomaterial delivery system based upon our preliminary and published data (Jiang, et al. Biomacromolecules, 2016) demonstrating ability to discriminately target and shuttle bioactive agents to specific ECM sub-components. Our hypothesis is that endothelial repair leading to vascular restoration can be controlled by delivering bioactive materials to the matrix with specificity to influence endothelial cells at ECM interfaces. Our investigation is supported by data showing a 7-fold enrichment of growth factors within ECM scaffolds accessed by TEMs, compared to soluble factors delivered free in solution, leading to maintenance of an ex vivo vascular endothelium for 28 days where none developed in its absence. This investigation is further enabled by a multidisciplinary team of collaborators in bioengineering, nanotechnology, peptide chemistry and nephrology to tailor the ex vivo renal vasculature with a panel of TEMs to develop testing platforms to study disease and therapies to repair renal vascular injury and reverse kidney disease.