Innovative In Vivo-like Model for Vascular Tissue Engineering

血管组织工程的创新类体内模型

基本信息

批准号：
8490420
负责人：
JOERG C. GERLACH
金额：
$ 46.88万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-09-01 至 2015-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8490420
关键词：
Address Angioblast Basic Science Biological Models Biomedical Engineering Bioreactors Blood Vessels Bone Marrow Stem Cell Calcium Cell Density Cell model Cells Cellular biology Coculture Techniques Cues Development Discontinuous Capillary Engineering Environment Experimental Models Fetal Liver Fiber Flow Cytometry Fluorescence Gases Gene Expression Generations Genes Harvest Heart Rate Heating Hematology Hematopoietic Hematopoietic stem cells Hepatic Hepatic Tissue Hepatocyte Hepatology High temperature of physical object Histology Human Hydroxyapatites In Vitro Label Laboratories Liver Mechanics Mediator of activation protein Modeling Molecular Biology Organ Organ Transplantation Organogenesis Outcome Pathway interactions Perfusion Play Principal Investigator Proteins Public Health Research Role Science Second Pregnancy Trimester Stem cells Structure Systems Analysis Technology Testing Time Tissue Engineering Tissue Harvesting Tissues Transfection Transplantation Vascularization abstracting angiogenesis base bone calcium phosphate cell type clinical application clinically significant density design fetal hematopoietic tissue improved in vitro Model in vivo innovation mortality physical conditioning postnatal prenatal pressure progenitor response scaffold shear stress stem cell niche success three-dimensional modeling tissue culture transplantation medicine vascular tissue engineering

项目摘要

DESCRIPTION (provided by applicant): The shortage of donor organs for transplantation suggests a need to develop engineered tissue transplants. Proper in vitro vascularization, a key prerequisite for the development of functional engineered tissue constructs, would enable adequate mass exchange, gas supply, and functional mediator exchange in high- density tissue cultures. The impact of physical and mechanical factors supporting endothelial differentiation has been investigated, but not in three-dimensional (3D) co-culture models. We propose to address this gap in cellular models and technology model systems, by analyzing neo-vascularization in an organ-like environment in vitro designed to mimic human organogenesis and that can vary physical conditions, such as flow- and pressure changes in the rhythm of the heart rate. In the fetal liver in vivo, angiogenesis occurs in hematopoietic and hepatic tissues that develop together. In our cell model for enabling vascularization in vitro, we therefore propose to investigate second trimester human fetal liver derived endothelial progenitors within fetal parenchymal cells, which contribute to hematopoietic and hepatic tissue vascularization. In the culture technology model, we propose to apply physical forces to control vascular structure formation, shear stress, perfusion flow and pressure changes. Additionally we will investigate the effects of calcium liberating hydroxyapatite scaffolds that mimics natural bone on formation of hematopoietic vascular sinusoids in the stem cell niche. RFP transfection labeled progenitors (hemangioblasts and angioblasts) and non-endothelial fetal liver cells will be cultured in 3D perfusion and the response to various physical-mechanical cues determined. Harvested cells will be analyzed by histology, flow cytometry, and gene expression, and compared to prenatal organ explants and postnatal organ tissues in vivo. The prior labeling of hemangioblasts will allow us to selectively distinguish between original hemangioblasts, endothelial- and non-endothelial cell types. The bioreactor model provides four independent interwoven hollow fiber compartments, enabling 3D perfusion with low gradients by decentral mass exchange and integral oxygenation. This has been proven to support vascularized tissue-like structure formation at high cell densities. We have already demonstrated that our 3D perfusion bioreactors support the spontaneous neo-tissue formation with neo-vascular hepatic structures and functionality in the laboratory and in clinical application for extracorporeal liver support. The innovation of our project is the specific experimental model that mimics the mass exchange in the native organ environment, allowing the fate of labeled fetal vascular progenitors to be studied during tissue formation, depending on different physical conditions. The project outcome will contribute to our understanding of the role of bioengineered supports and physical forces in establishing functional 3D engineered neo-vascular constructs in hematopoietic and hepatic tissues. (End of Abstract)

描述（由申请人提供）：用于移植的供体器官的短缺表明需要开发工程组织移植。适当的体外血管化是功能工程组织构建体开发的关键先决条件，它将在高密度组织培养物中实现充分的质量交换、气体供应和功能介质交换。已经研究了支持内皮分化的物理和机械因素的影响，但没有在三维 (3D) 共培养模型中进行研究。我们建议通过分析体外类似器官环境中的新血管形成来解决细胞模型和技术模型系统中的这一差距，该环境旨在模拟人类器官发生并且可以改变物理条件，例如生物节律中的流量和压力变化。心率。在体内的胎儿肝脏中，血管生成发生在共同发育的造血组织和肝组织中。因此，在我们用于体外血管化的细胞模型中，我们建议研究胎儿实质细胞内妊娠中期人类胎儿肝脏来源的内皮祖细胞，这些祖细胞有助于造血和肝组织血管化。在培养技术模型中，我们建议应用物理力来控制血管结构形成、剪切应力、灌注流量和压力变化。此外，我们将研究模拟天然骨的钙释放羟基磷灰石支架对干细胞微环境中造血血管窦形成的影响。 RFP 转染标记的祖细胞（成血管细胞和成血管细胞）和非内皮胎儿肝细胞将在 3D 灌注中培养，并确定对各种物理机械线索的反应。收获的细胞将通过组织学、流式细胞术和基因表达进行分析，并与产前器官外植体和产后体内器官组织进行比较。预先标记成血管细胞将使我们能够选择性地区分原始成血管细胞、内皮细胞和非内皮细胞类型。该生物反应器模型提供四个独立的交织中空纤维隔室，通过分散的质量交换和整体充氧实现低梯度的 3D 灌注。这已被证明可以支持高细胞密度下血管化组织样结构的形成。我们已经证明，我们的 3D 灌注生物反应器在实验室和体外肝脏支持的临床应用中支持具有新生血管肝脏结构和功能的自发新组织形成。我们项目的创新之处在于模拟天然器官环境中的物质交换的特定实验模型，允许根据不同的物理条件在组织形成过程中研究标记的胎儿血管祖细胞的命运。该项目的成果将有助于我们了解生物工程支撑和物理力在造血和肝组织中建立功能性 3D 工程新血管结构中的作用。（摘要完）