CAREER: Tissue engineering of developing human heart: The role of microenvironment in cardiac development and congenital heart disease

发育中的人类心脏在包括血液流动、组织生物力学和组织组成在内的各种影响下具有显著的自我转换能力。这些参数的改变可能会导致心脏的异常生长，增加先天性(出生时或出生前)心脏病的发生率。这个职业项目的总体目标是利用先进的生物工程工具，包括3D生物打印和人类诱导多潜能干细胞技术，创造出可以作为人类心脏高保真模型的生物人造组织结构。这些工程模型作为一个研究平台，能够检查人类心脏正常发育以及各种心脏缺陷的形成所涉及的细胞过程。这项研究将与埃默里大学和佐治亚理工学院的联合生物医学工程项目中旨在建立一个充满活力的科学社区的多个教育项目相结合。基本的生物材料设计和生物打印、干细胞培养和分化以及心脏细胞生物学原理将整合到各种教育活动中。教育计划包括设计和开发教育工具，并通过(A)联合暑期实习计划；(B)一年两次的生物医学科学和工程展览；以及(C)在埃默里大学儿童心脏研究和成果(HERO)中心开展的外联活动，向当地高中生推广。此外，该项目还计划开发一门新的夏季混合课程，专门介绍3D生物打印的基本原理及其在各种生物医学应用中的应用。研究人员的研究重点是使用多学科方法设计和开发微/纳米级组织工程技术，最终目标是生成功能性生物人工组织和器官。为了实现这一目标，该职业项目集中在：(1)利用人类诱导多能干细胞来源的心肌细胞(HiPSC-CMS)和内皮细胞(ECs)，在体外构建3D人类心脏模型(3D-iDHs)，包括胚胎、胎儿、新生儿和成人，这些细胞可以在几周内显示出功能成熟/稳定；以及(2)评估3D-iDHs破译先天性心脏病(CHDS)临床相关机制的能力，例如左心发育不良综合征和扩张型心肌病。最先进的3D生物打印系统将被用于制造设备，允许精确控制组织微环境，以实现功能和结构仿生。该项目将在初步成果的基础上，利用HiPSC来源的心肌细胞创建各种可灌流的3D心脏组织结构，以重建发育中的人类心脏的动态微环境。多材料3D生物打印能够创建可灌流的心腔状构造，允许心肌细胞暴露于不同的环境因素，如血流动力学、僵硬和组织组成(目标1)。然后，该项目将探索这些3D-iDHH的用途，以破译CHDS背后的微环境机制(目标2)。这项研究最终可能导致开发新的、更有效的临床干预和/或治疗方法来治疗各种冠心病。更广泛地说，该设备可以与其他组织/器官模型集成在一个芯片上，以实现对各种发育障碍的系统级了解。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The developing human heart has a remarkable ability to transform itself under a variety of influences, including blood flow, tissue biomechanics, and tissue composition. Alterations in these parameters may result in abnormal growth of the heart, increasing the incidence of congenital (present at or before birth) heart disease. The overall goal of this CAREER project is to utilize advanced bioengineering tools, including 3D bioprinting and human induced pluripotent stem cell technologies, to create bioartificial tissue constructs that can serve as high-fidelity models of the human heart. The engineered models serve as a research enabling platform to examine cellular processes involved in normal development of the human heart as well as the formation of various heart defects. The research will be integrated with multiple educational programs geared towards building a dynamic scientific community in the joint biomedical engineering program at Emory University and Georgia Institute of Technology. The fundamental biomaterials design and bioprinting, stem cell culture and differentiation, and cardiac cellular biology principles will be integrated into various educational activities. Education plans include design and development of educational tools and outreach to local high school students through (A) a joint summer internship program; (B) bi-annual biomedical science and engineering exhibitions; and (C) outreach activities in the Children's Heart Research and Outcomes (HeRO) Center at Emory University. Further, the project includes plans to develop a new summer hybrid course that is specifically designed to introduce the basic principles of 3D bioprinting and its use in various biomedical applications.The investigator’s research focus is on using a multidisciplinary approach to design and develop micro/nano-scale tissue engineering technologies with the ultimate goal of generating functional bioartificial tissues and organs. Toward this goal, this CAREER project focuses on: (1) Engineering 3D in vitro developing human heart models (3D-iDHHs)--embryonic, fetal, neonatal and adult--using human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) and endothelial cells (ECs) that display functional maturity/stability for several weeks; and (2) Evaluating the ability of 3D-iDHHs to decipher clinically relevant mechanisms of congenital heart diseases (CHDs), e.g., hypoplastic left heart syndrome and dilated cardiomyopathy. A state-of-the-art 3D bioprinting systems will be used to build devices, allowing precise control of the tissue microenvironment to achieve functional and structural biomimicry. The project will build upon preliminary achievements to create various perfusable 3D cardiac tissue constructs utilizing hiPSC-derived cardiac cells to reconstruct the dynamic microenvironment of the developing human heart. Multi-material 3D bioprinting enables creating perfusable heart chamber-like constructs, allowing for exposure of cardiac cells to varying environmental factors such as flow hemodynamics, stiffness, and tissue composition (Aim 1). The project will then explore the utility of these 3D-iDHHs to decipher microenvironmental mechanisms underlying CHDs (Aim 2). This research could ultimately lead to the development of novel and more effective clinical interventions and/or therapeutics to treat various CHDs. More broadly, this device could be integrated with other tissue/organ models in a human-on-a-chip for a systems-level understanding of various developmental disorders.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.