Understanding Biomaterials Stimulated Organ Regeneration

了解生物材料刺激器官再生

• 批准号: RGPIN-2017-05410
• 负责人: Griffith, May
• 金额: $ 2.04万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=711635
• 关键词: Understanding; Biomaterials; Stimulated; Organ; Regeneration

Many biomaterials being tested or used clinically are plastic-based with promising short-term results in animals and early clinical trials. Longer term results, however, can be sub-optimal to harmful. Biomaterials based on the extracellular matrix (ECM) are now being tested for stimulating regeneration but are they actually safer as believed, as there have been reported fatalities. My long-term goal is to understand how biomaterials and cells interact, to identify the "good" biomaterials that promote safe regeneration and avoid "bad" ones leading to problems. Extracellular vesicles (EVs) are key components in intercellular communication. They contain a wide range of cargo (mRNA, microRNA, proteins, signaling molecules and lipids) that modulate regeneration and have been proposed as cell-free therapeutic agents. However, there is no information on biomaterials-induced EV production and regeneration. I will test the hypothesis that EV are effectors for biomaterials-stimulated regeneration and that their pattern of expression and cargo will allow us to distinguish the good versus bad, or neutral biomaterials in terms of long-term outcomes. I will use the cornea as an experimental model as there is a long history of corneal implants made from a range of biomaterials with documented long-term clinical outcomes that can be used to aid in producing the EV “barcodes” (size, content, surface markers). I will begin with biomaterials in the form of implants that are designed as pro-regeneration scaffolds. We will fabricate implants made from methacrylates (poor regeneration) to blends of pHEMA/collagen (mediocre regeneration) to recombinant human collagen (excellent regeneration) and new materials based on mimetic analogs of collagen. Polyethylene glycol (PEG) hydrogels have been shown to be passive, and biocompatible by virtue of their inertness. A set of PEG-based scaffolds will be fabricated where we will add incremental amounts of collagen and collagen-like peptides until these scaffolds promote optimal growth of corneal and nerve cells, but not activate antigen presenting dendritic cells, in order to examine the changes in EV profile with increasing cell-friendliness. We will define EV expression based on their sub-type (microvesicles/microparticles/ectosomes; exosomes; or apoptotic bodies) and their protein and mRNA cargoes during cell-material interactions in vitro, by seeding cells onto materials as 2D constructs and compare their interactions as “implants” in 3D constructed corneal equivalents that we have characterized very well. These interactions will be observed in real time by confocal microscopy using two-photon confocal microscopy. In vitro results will be corelated with in vivo implantation. Our will be a barcode of EVs and contents that will point to biomaterials promoting successful regeneration versus those that give poor regeneration or an adverse reaction.

许多正在测试或临床使用的生物材料都是基于塑料的，在动物和早期临床试验中有希望的短期效果。然而，长期的结果可能不是最佳的，甚至是有害的。基于细胞外基质（ECM）的生物材料目前正在进行刺激再生的测试，但它们是否真的像人们认为的那样安全，因为有死亡的报道。我的长期目标是了解生物材料和细胞如何相互作用，识别促进安全再生的“好”生物材料，避免导致问题的“坏”生物材料。细胞外囊泡（EVs）是细胞间通讯的重要组成部分。它们含有广泛的货物（mRNA, microRNA，蛋白质，信号分子和脂质），可调节再生，并已被提议作为无细胞治疗剂。然而，目前还没有关于生物材料诱导EV产生和再生的信息。我将测试EV是生物材料刺激再生的效应器的假设，它们的表达模式和货物将使我们能够区分好与坏，或从长期结果来看中性生物材料。我将使用角膜作为实验模型，因为由一系列生物材料制成的角膜植入物有着悠久的历史，并记录了长期临床结果，可用于帮助生产EV“条形码”（大小，内容，表面标记）。我将从植入物形式的生物材料开始，它被设计成促进再生的支架。我们将制作由甲基丙烯酸酯（再生能力差）、pHEMA/胶原蛋白混合物（再生能力一般）、重组人胶原蛋白（再生能力优异）和基于胶原蛋白模拟类似物的新材料制成的植入物。聚乙二醇（PEG）水凝胶已被证明是被动的，并且由于其惰性而具有生物相容性。我们将制作一套基于聚乙二醇的支架，在其中我们将增加胶原蛋白和胶原样肽的量，直到这些支架促进角膜和神经细胞的最佳生长，但不激活抗原呈递树突状细胞，以检查EV谱随着细胞友好性的增加而变化。我们将根据它们的亚型（微泡/微粒/外泌体、外泌体或凋亡小体）及其在体外细胞-物质相互作用过程中的蛋白质和mRNA表达来定义EV表达，方法是将细胞作为2D构建体植入材料，并将它们的相互作用作为“植入物”与我们已经很好地描述的3D构建角膜等效物进行比较。这些相互作用将通过双光子共聚焦显微镜实时观察。体外结果将与体内植入相关。这将是一个电动汽车的条形码和内容，将指出生物材料促进成功再生与那些再生不良或不良反应。