Nanoscale Assembly of Bioactive Ligands to Enhance Endothelial Differentiation

生物活性配体的纳米级组装以增强内皮分化

• 批准号: 8241196
• 负责人: Wei Shen
• 金额: $ 18.09万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-01-09 至 2013-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8241196
• 关键词: Address; Adhesives; Autologous; Binding Sites; Biomimetics; CD34 gene; Cells; Characteristics; Cysteine; Developmental Biology; Endothelial Cells; Engineering; Exhibits; Fibronectins; Future; Hematopoietic; Human; Integrins; Ligands; Literature; Methods; Molecular Structure; Peptides; Pluripotent Stem Cells; Positioning Attribute; Production; Proliferating; Protein Engineering; Research; Research Personnel; Site; Source; Stem cells; Stents; Structure; Surface; Technology; Testing; Tissues; Umbilical Cord Blood; Variant; Vascular Endothelial Growth Factors; Vascular Graft; Work; base; biological systems; density; design; experience; human embryonic stem cell; induced pluripotent stem cell; mimetics; nanoscale; neovascularization; polypeptide; self assembly; stem cell technology; success; surface coating; synergism; Address; Adhesives; Autologous; Binding Sites; Biomimetics; CD34 gene; Cells; Characteristics; Cysteine; Developmental Biology; Endothelial Cells; Engineering; Exhibits; Fibronectins; Future; Hematopoietic; Human; Integrins; Ligands; Literature; Methods; Molecular Structure; Peptides; Pluripotent Stem Cells; Positioning Attribute; Production; Proliferating; Protein Engineering; Research; Research Personnel; Site; Source; Stem cells; Stents; Structure; Surface; Technology; Testing; Tissues; Umbilical Cord Blood; Variant; Vascular Endothelial Growth Factors; Vascular Graft; Work; base; biological systems; density; design; experience; human embryonic stem cell; induced pluripotent stem cell; mimetics; nanoscale; neovascularization; polypeptide; self assembly; stem cell technology; success; surface coating; synergism

DESCRIPTION (provided by applicant): Endothelial cells have important biomedical applications ranging from enhancing the patency of engineered vascular grafts and stents to promoting neovascularization in ischemic tissues. But their limited availability hinders the success of endothelial-cell-related technologies. The advances in stem cell technology offer a unique opportunity to address this issue. In particular, endothelial cells have been derived from human pluripotent stem cells (hPSCs), which can proliferate extensively and virtually provide an unlimited cell source. The recent success in making induced PSCs (iPSCs) offers additional advantages in providing immunologically compatible autologous hPSCs and enabling "personalized" therapy in the future. The key to exploiting this opportunity to advance endothelial-cell-related technologies is our ability to guide endothelial differentiation. In currently used methods, hPSCs are differentiated into hemangioblasts, which have both hematopoietic and endothelial potentials, followed by differentiation of hemangioblasts into endothelial cells in the presence of VEGF and fibronectin(FN)-coated surfaces. VEGF and FN are both essential for efficient endothelial differentiation, and they exhibit a synergistic effect due to the unique structure of FN, which has a cell-adhesive site and a VEGF-binding site positioned in nanoscale proximity. However, naturally-derived FN has batch-to-batch variations. In addition, covalently immobilized FN has structural change that blocks the cell- adhesive ligand; physically adsorbed FN preserves the active cell-adhesive domain but does not allow precise control of surface ligand density. Therefore, cell microenvironments created with FN are not tightly controlled, hampering consistent production of endothelial cells from stem cells. This problem can be addressed by using well-controlled synthetic materials that recapitulate the essential molecular structure underlying the synergistic effect of VEGF and FN in regulating endothelial differentiation. The objective of this application is to develop synthetic materials having the essential structural characteristics underlying the synergistic effect of VEGF and FN and to use these materials to guide endothelial differentiation of human iPSC-derived hemangioblasts. Our central hypothesis is that a cell-adhesive peptide and a VEGF-mimetic peptide fused to a pair of heterodimerizing coiled-coils, respectively, can be brought into nanoscale proximity through coiled-coil self- assembly and the materials functionalized with the heterodimer, together with soluble factors, will create well- controlled cell microenvironments for efficient and reproducible endothelial differentiation of iPSC-derived hemangioblasts. The specific aims are: (1) design, synthesize, characterize, and immobilize the polypeptides that self-assemble to present a cell-adhesive peptide and a VEGF-mimetic peptide in nanoscale proximity; (2) examine endothelial differentiation of human iPSC-derived hemangioblasts on the polypeptide-functionalized substrates. Successful completion of this project will result in well-controlled, biomimetic cell microenvironments for efficient and robust endothelial differentiation of iPSC-derived hemangioblasts. PUBLIC HEALTH RELEVANCE: The proposed project aims to engineer rationally designed, well-controlled synthetic cell microenvironments to guide efficient and reproducible endothelial differentiation of hemangioblasts derived from human induced pluripotent stem cells. Such derived endothelial cells will have important biomedical applications ranging from enhancing the patency of engineered vascular grafts and stents to promoting neovascularization in ischemic tissues.

描述（由申请人提供）：内皮细胞具有重要的生物医学应用，从增强工程血管移植物和支架的通畅到促进缺血性组织的新血管化。但是它们有限的可用性阻碍了内皮细胞相关技术的成功。干细胞技术的进步为解决这个问题提供了独特的机会。特别是，内皮细胞已源自人多能干细胞（HPSC），它们可以广泛，实际上提供无限的细胞来源。最近制作诱导PSC（IPSC）的成功在提供免疫学兼容的自体HPSC并在将来实现“个性化”疗法方面提供了其他优势。利用这一机会推进内皮细胞相关技术的关键是我们指导内皮分化的能力。在当前使用的方法中，HPSC被分化为血管细胞，这些血管细胞具有血管细胞和内皮电位，随后在存在VEGF和Fibronectin（FN）覆盖面的情况下将血管细胞分化为内皮细胞。 VEGF和FN对于有效的内皮分化都是必不可少的，由于FN的独特结构，它们具有协同作用，该结构具有细胞粘附部位和位于纳米级附近的VEGF结合位点。但是，天然衍生的FN具有批处理变化。此外，共价固定的FN具有结构变化，可阻断细胞粘合剂配体。物理吸附的FN可保留活性细胞粘附域，但不能精确控制表面配体密度。因此，用FN产生的细胞微环境并未受到严格控制，从而阻碍了干细胞中内皮细胞的一致产生。可以通过使用良好控制的合成材料来解决此问题，该材料概括了VEGF和FN在调节内皮分化中的协同作用的基本分子结构。该应用的目的是开发具有VEGF和FN协同作用的基本结构特征的合成材料，并使用这些材料来指导人IPSC衍生的血管细胞的内皮分化。我们的中心假设是，可以分别将与一对异二聚体盘绕的螺旋线融合的细胞粘附肽和VEGF模拟肽分别融合到纳米级的接近纳米级接近性，并通过盘旋螺旋圈的自我组装以及与异性含量的材料一起功能良好，可以与可溶性良好的因素相比，将良好的细胞相关性和良好的相关性以及良好的良好相关性和良好的效率相关性，并有效地既有能力又有效率的效率。 IPSC衍生的血管细胞。具体目的是：（1）设计，合成，表征和固定自我组装以在纳米级接近中呈现细胞粘附性肽和VEGF模拟肽的多肽； （2）检查多肽官能化底物上人IPSC衍生的血管细胞的内皮分化。该项目的成功完成将导致良好控制的仿生细胞微环境，以实现IPSC衍生的血管细胞的有效且健壮的内皮分化。 公共卫生相关性：拟议的项目旨在设计出理性设计的，控制良好的合成细胞微环境，以指导源自人类诱导的多能干细胞的血管细胞的有效且可再现的内皮分化。这种衍生的内皮细胞将具有重要的生物医学应用，从增强工程血管移植物和支架的通畅到促进缺血性组织中的新血管形成。