Functional role and microfluidic gene chip analysis of proangiogenic chemokines in the course of ischemia-dependent endothelial progenitor cell (EPC) vasculogenesis

内皮祖细胞（EPCs）已被证明充分有助于缺血区域的血管重建。EPCs的发现已经实质性地改变了我们对成人组织血管生成的看法，表明骨髓来源的细胞可以促进新血管的形成。然而，经过10年的积极研究，尚未达成共识的外观EPCs。目前普遍认为EPCs通过释放旁分泌血管生成因子促进血管生成和血管发生。这些血管生成因子之一，我的兴趣焦点是多效性细胞因子巨噬细胞迁移抑制因子（MIF）。基于最近发现MIF表现出趋化因子样功能并作为CXC趋化因子受体CXCR4（也在EPCs上表达的调节祖细胞迁移的主要受体）的非同源相互作用而相互作用，已经表明MIF有助于EPCs的缺血依赖性募集。基于这些结果，我现在想阐明促血管生成趋化因子，如MIF和CXCL12在内皮细胞和EPCs中缺氧依赖性诱导后的功能作用。此外，将进行趋化因子-细胞因子多重测定、静态粘附实验和动态迁移测定（趋化性），以在功能上支持MIF/CXCR 4轴和CXCL 12/CXCR 4轴的作用，反之亦然。为了回答关于异质性EPC的性质的基本问题，将开发一种利用单细胞FACS分选和市售的基于微流体的技术的单细胞分析的创新方法，以同时对给定细胞群中的许多单个细胞进行48个基因靶点的定量PCR基因表达分析。该计划的最后一步涉及另一种创新的方法，即用于组织转移的转基因游离皮瓣，以扩大我的研究组合的临床范围。

Endothelial progenitor cells (EPCs) have been shown to amply contribute to the revascularization of ischemic areas. The discovery of EPCs has substantively altered our view of adult tissue angiogenesis, indicating that bone marrow-derived cells can contribute to new blood vessel formation. However, after 10 years of vigorous research no consensus about the appearance of EPCs has been reached yet. It is widely accepted that EPCs promote angiogenesis and vasculogenesis by virtue of the release of paracrine angiogenic factors which they carry with them as cargo. One of these angiogenic factors and my focus of interest is the pleiotropic cytokine macrophage migration inhibitory factor (MIF). Based on the recent discovery that MIF exhibits chemokine-like functions and interacts as a non-cognate interaction of the CXC chemokine receptor CXCR4, a major receptor regulating progenitor cell migration that is also expressed on EPCs, it has been shown that MIF contributes to ischemia-dependent recruitment of EPCs. Based on these results I now want to clarify the functional role of proangiogenic chemokines, such as MIF and CXCL12 after hypoxia dependent induction in endothelial cells and EPCs. Furthermore chemokine-cytokine-multiplex assays, static adhesion experiments and dynamic transmigration assays (chemotaxis) will be performed to functional underlie the role of the MIF/CXCR4 axis and CXCL12/CXCR4 axis vice versa. To answer fundamental questions regarding the nature of the heterogeneous EPCs, an innovative approach to single cell analysis utilizing single cell FACS sorting and commercially available microfluidic-based technology to perform quantitative PCR gene expression analysis across 48 gene targets simultaneously for many individual cells within a given cell population will be developed. A last step of the program deals with another innovative approach of genetically modified free flaps for tissue transfer to expand the clinical spectrum of my research portfolio.