NANO-PATTERNING OF BIOMATERIALS FOR BLOOD-VESSEL FORMATION IN ARTIFICIAL TISSUES

用于人造组织中血管形成的生物材料纳米图案化

基本信息

批准号：
8484754
负责人：
Patrick Benitez
金额：
$ 3.19万
依托单位：
STANFORD UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-06-25 至 2017-06-24
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8484754
关键词：
Actins Adhesions American Analysis of Variance Angiopoietin-1 Animal Model Area Arginine Artificial Organs Aspartic Acid Biocompatible Materials Biology Bioreactors Blood Vessels Cell Culture Techniques Cell physiology Cell-Matrix Junction Cells Chi-Square Tests Chimeric Proteins Clinic Clinical Coculture Techniques Computer Analysis Cytoplasmic Tail Cytoskeletal Modeling DNA Data Development Elastin Endothelial Cells Engineering Enzyme-Linked Immunosorbent Assay Extracellular Matrix Faculty Failure Fibronectins Fluorescence Microscopy Focal Adhesion Kinase 1 Glean Glycine Growth Factor Human Image Analysis Implant In Vitro Integrins Lead Left Length Life Ligands Measures Mechanical Stimulation Mediating Medical Mentors Mesenchymal Metabolic Molecular Organ Organ Transplantation Oxygen Patients Peptide Hydrolases Perfusion Phosphorylation Process Protein Engineering Proteins Radial Recombinants Regenerative Medicine Regression Analysis Research Reverse Transcriptase Polymerase Chain Reaction Signal Transduction Specific qualifier value Speed Staining method Stains Stem cells Structure Surface Talin Technology Testing Thick Tissue Engineering Tissues Training Translating Translations Transplantation Vascular Endothelial Growth Factors Vascularization Work base blebbistatin cell growth cell motility cellular engineering clinically relevant implantation improved in vivo meetings monolayer nano nanofiber nanopattern nanoscale novel polymerization prevent professor receptor regenerative therapy scaffold two-dimensional vector

项目摘要

DESCRIPTION (provided by applicant): Patients suffering from failure of a vital organ can be treated with whole organ transplantation; transplantation alone, however, cannot meet the public's medical needs due to the limited supply of donated organs. Artificial tissues present an alternative to donated organs, but our inability to engineer functional microvessels within such constructs broadly prevents the development of clinically effective artificial tissues. Because all tissue- scale regenerative therapies require perfusion, the ability to form functional microvasculature is paramount. Upon implantation of bulk artificial tissues without microvasculature, cells on the inside die from lack of oxygen, leaving a shell of live cells about 0.2 mm thick. Artificial vascularization will prevent this by creating a volume- spanning perfusion-competent network and by enabling swift vascular integration after implantation. To engineer microvasculature, we propose a novel biomaterials strategy: nanoscale clustering of cell- matrix adhesion ligands. Previous work on 2D surfaces has shown that clustering of ligands increases growth factor sensitivity and motility via receptor clustering. Research using animal models has shown that expression of molecular disruptors of receptor clustering is associated with a decrease in both branching and maturation. Though ligand clustering and receptor clustering are related thermodynamically, it is unknown whether nanoscale ligand clustering will lead to morphologically appropriate microvasculature in a 3D, bulk biomaterial. To answer this question, we have developed a nanofibrous biomaterial that can be fabricated at a specified bulk concentration and nanoscale clustering of adhesion ligands. By mimicking the nanoscale order of the native the extracellular matrix, we expect to achieve organotypic blood-vessel structure formation in vitro. We specifically hypothesize that clustering of adhesion ligands will upregulate three essential cellular process that lead to formation of blood-vessels in vivo: (1) growth factor sensitivity, (2) cell motility, and (3) vessel branching and maturation. Growth factor sensitivity will be assessed by measuring proliferation, metabolic activity, and protease secretion. Motility, as parameterized by cell speed and persistence length, and cytoskeletal organization will be assessed by quantitative image analysis. Branching and maturation will be assessed by immunostaining for appropriate markers and computational analysis of morphological data. The biomaterials proposed here can be further developed as an implant for regenerative medicine by incorporating non- overlapping technologies such as co-culture of tissue-specific stems cells, growth factor delivery, and bioreactor/ mechanical stimulation. My mentor Sarah Heilshorn, an expert in protein-based materials engineering, and our collaborator John Cooke, a senior professor of microvascular signaling biology, have developed an appropriate training plan to accomplish this project.

描述（由申请人提供）：患有重要器官失败的患者可以通过整个器官移植治疗；但是，由于捐赠器官的供应有限，仅移植就无法满足公众的医疗需求。人造组织提出了捐赠器官的替代方案，但是我们无法在这种构造中设计功能性微血管，从而广泛地阻止了临床上有效的人造组织的发展。因为全部组织尺度再生疗法需要灌注，形成功能性微脉管系统的能力至关重要。在植入无微血管造成的散装人造组织后，内部的细胞死于缺乏氧气，留下约0.2 mm厚的活细胞壳。人工血管形成将通过创建一个体积的灌注能力网络，并通过植入后迅速血管整合来防止这种情况。对于工程师的微脉管系统，我们提出了一种新型的生物材料策略：细胞基质粘附配体的纳米级聚类。先前在2D表面上的工作表明，配体的聚类通过受体聚类提高了生长因子敏感性和运动性。使用动物模型的研究表明，受体聚类的分子破坏者的表达与分支和成熟的降低有关。尽管配体聚类和受体聚类在热力学上是相关的，但尚不清楚纳米级配体聚类是否会导致在3D，大量的生物材料中导致形态上适当的微脉管系统。为了回答这个问题，我们开发了一种纳米纤维生物材料，可以在粘附配体的指定体积浓度和纳米级聚类中制造。通过模仿天然的细胞外基质的纳米级顺序，我们希望在体外实现器官型血管结构形成。我们特别假设粘附配体的聚类将上调三个必需的细胞过程，从而导致血管形成体内：（1）生长因子敏感性，（2）细胞运动和（3）血管分支和成熟。生长因子敏感性将通过测量增殖，代谢活性和蛋白酶分泌来评估。通过细胞速度和持久性长度参数，将通过定量图像分析评估运动性。分支和成熟将通过免疫染色来评估适当的标记和形态数据的计算分析。通过纳入非重叠技术，例如组织特异性干细胞，生长因子递送和生物反应器/机械刺激，可以通过纳入非重叠技术来进一步开发作为再生医学的植入物。我的导师Sarah Heilshorn是蛋白质材料工程专家，我们的合作者John Cooke是微血管信号生物学的高级教授，已经制定了适当的培训计划来完成该项目。