Generating multilayered engineered heart tissue patches to mimic physiological thickness and function using open microfluidics

使用开放微流体生成多层工程心脏组织补片以模拟生理厚度和功能

• 批准号: 10230405
• 负责人: Amanda Jean Haack
• 金额: $ 4.12万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-06-16 至 2025-06-15
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10230405
• 关键词: Generating; multilayered; engineered; heart; tissue

PROJECT SUMMARY/ABSTRACT Heart disease is the leading cause of death in the U.S., often driven by irreversible cardiac tissue damage leading to heart failure. Cardiac tissue does not naturally regenerate, and thus is an important area of focus for tissue engineering. Previous development into engineered heart tissue (EHT) "patches" with some functional architecture such as pre-patterned vasculature and alignment has shown promising results when implanted into small animal models. Moreover, injected stem cells and implanted cardiac "sheets" have shown some success in restoring some cardiac function when implanted into infarcted hearts of large animals or humans. Despite these successes, scaling EHT that incorporates important functional features such as vascularization and alignment to a physiological thickness (cm-scale) remains a major engineering challenge. The overarching goal of this proposal is to generate in vitro physiologically thick heart tissue patches that can ultimately be implanted into patients to replace damaged tissue. Two key considerations for recapitulating native tissue are (1) cardiac tissue is highly vascularized, and (2) alignment of cells and extracellular matrix within each physiological layer is critical to function. We address these challenges utilizing novel open microfluidic patterning approaches. Our open microfluidic technological advancement offers unique benefits to EHT; for example, it is compatible with virtually any hydrogel, including standard extracellular matrix material such as collagen and fibrin, used extensively for EHT. It is also compatible with specialized stimuli-responsive engineered hydrogels, opening up possibilities for complex engineered tissues with spatial and temporal control. Further, the flow of precursor fluid is driven by passive surface tension forces; thus, sensitive stem-cell- derived cells are not exposed to shear stress from extrusion through a needle or photochemical crosslinking, which are requirements for other tissue fabrication techniques such as 3D bioprinting. Finally, a large area (cm- scale) can be patterned with a single pipetting step, making this fabrication approach ideal for generating large (cm-scale) tissues. In this proposal, I apply these unique attributes of open microfluidic pattering to EHT. Specifically, the ability to pattern enzymatically degradable gels through a background of standard cell culture ECM materials such as collagen or fibrin enables the patterning of complex vasculature in three dimensions. I will also take advantage of previously demonstrated modular stacking of open microfluidic devices and suspended microfluidics to generate aligned EHT patches. In these patches, the tissue is anchored on either end, inducing ECM remodeling and alignment. Each layer is generated and aligned independently. Then, they are stacked together at an angle from the previous layer, creating a multilayered tissue mimicking the heart's helical tissue fiber alignment. As such, I will address in two independent aims, vascularization and tissue alignment of physiologically thick EHT using open microfluidics.

项目总结/摘要 心脏病是美国的主要死因，通常由不可逆转的心脏组织损伤驱动 导致心力衰竭心脏组织不能自然再生，因此是心脏移植的重要关注领域。 组织工程学先前开发的工程心脏组织（EHT）“补丁”具有一些功能 诸如预图案化脉管系统和对准的结构在植入时显示出有希望的结果 小动物模型。此外，注射的干细胞和植入的心脏“片”显示出一些 当植入大型动物或人类的梗塞心脏时，成功地恢复了一些心脏功能。 尽管取得了这些成功，但结合重要功能特征（如血管化）的EHT规模 并且与生理厚度（厘米尺度）对准仍然是主要的工程挑战。 该提案的首要目标是在体外产生生理厚的心脏组织贴片， 最终植入患者体内以替换受损组织。概括的两个关键考虑因素 天然组织是（1）心脏组织高度血管化，和（2）细胞和细胞外基质的排列 每个生理层内的细胞对功能至关重要。我们利用新的开放式解决这些挑战 微流体图案化方法。我们的开放式微流体技术进步提供了独特的优势， 例如，它与几乎任何水凝胶相容，包括标准细胞外基质材料 如胶原蛋白和纤维蛋白，广泛用于EHT。它也与专门的刺激响应兼容 工程水凝胶，为复杂的工程组织开辟了可能性， 控制此外，前体流体的流动是由被动表面张力驱动的;因此，敏感的干细胞-细胞粘附剂可以被释放。 衍生的细胞不暴露于来自通过针挤出或光化学交联的剪切应力， 这是其他组织制造技术如3D生物打印的要求。最后，大面积（cm- 规模）可以用单个移液步骤图案化，使得这种制造方法对于产生大的 （cm尺度）组织。在这个提议中，我将开放微流体图案化的这些独特属性应用于EHT。 具体地说，通过标准细胞培养物的背景， ECM材料如胶原蛋白或纤维蛋白使得能够在三维中形成复杂脉管系统的图案。我 还将利用先前展示的开放式微流体装置的模块化堆叠， 悬浮的微流体以产生对齐的EHT贴片。在这些补片中，组织固定在 端，诱导ECM重塑和对齐。每个层都是独立生成和对齐的。然后他们 与前一层以一定角度堆叠在一起，形成了一个模仿心脏的多层组织。 螺旋组织纤维排列。因此，我将在两个独立的目标，血管化和组织 使用开放式微流体技术的生理厚EHT的对准。