Engineering a Novel Bio-Scaffold for Hepatic Tissue Restoration and Drug Screening

与肝病相关的健康问题困扰着数百万人，导致超过7万人死亡 每年在美国。部分由于人口老龄化，预计肝病将会增加 在接下来的二十年里，显著增加了对更有效的治疗方法和 提高了移植的成功率。不幸的是，目前还没有有效的治疗方法来抑制这种病理 可供移植的肝脏仍然短缺。这一挑战进一步加剧了 同种异体反应导致移植排斥反应。然而，一个可行的解决方案是使用模型肝脏 精确模拟体内肝组织的生物力学和生化功能的系统。 此外，在保持功能的同时扩大受体自体肝细胞的替代方法是 是产生供移植用的肝脏系统的有效方法。然而，虽然活体肝脏模型 已经尝试过使用，还没有成功地在体外扩增自体肝细胞 使用体内模型系统成功植入以缓解受者的肝功能衰竭。我的实验室有 最近证明了这种方法的成功，我们已经建立了一种有效的体外3D肝细胞 培养体系快速扩张。此外，我们的前期工作显示出很大的应用前景 使用我们创新的内部设计的3D支架系统进行体内收养植入的系统。因此， 这项提议的目的是开发一种在新型3D打印中快速扩增肝细胞的方法 用于体内组织修复和体外药物筛选的肝脏有机化合物组装的生物支架。这个 中心假设是，种植在一种新型生物材料支架中的原代肝细胞将表现出类似的 代谢功能、结构和生物力学特性与原始肝组织的代谢功能、结构和生物力学特性。的成功之处 在肝脏受损的小鼠模型中，这种方法将在移植后恢复肝功能。这个 流变学生物材料调整、3D生物打印和培养方法的创新组合，利用 新的生物支架将被应用于追求两个特定的目标：1)设计用于筛选的体外模型 3D打印生物支架靶向肝细胞治疗药物及2)植入型生物支架的研制 用于体内组织修复以减轻小鼠模型肝功能衰竭的肝脏有机化合物。这些调查 将为新的3D培养系统建立一个平台，用于严格的体外诊断筛选和 生理性恢复失败肝功能的活体过继移植方法。建议的工作是 由于预期结果将为未来利用生物材料进行研究建立一个平台，因此意义重大 工程细胞种子支架，以恢复组织功能和追求药物发现。

Health issues associated with liver diseases afflict millions of individuals and account for over 70,000 deaths annually in the United States. Due in part to an aging population, liver diseases are expected to rise significantly over the next two decades, increasing the need for more effective treatment therapies and increased success rates with transplants. Unfortunately, there are no effective treatments to curb the pathology and there remains a shortage of available livers for transplantation. This challenge is further compounded with alloreactive responses leading to transplant rejection. However, a viable solution is the use of a model liver systems that accurately mimic the biomechanical and biochemical functioning of in vivo liver tissue. Additionally, alternative methods to expand recipient autologous hepatic cells while maintaining function would serve as efficient methods to generate liver systems for transplantation. However, while liver models for in vivo use have been attempted, none have yet successfully expanded autologous hepatic cells in vitro followed by successful implantation to alleviate liver failure in recipients using an in vivo model system. My laboratory has recently demonstrated success in this approach, where we have established an effective in vitro 3D hepatocyte culture system for rapid expansion. Furthermore our preliminary work shows great promise in applying the system for in vivo adoptive implantation using our innovative in-house designed 3D scaffold system. Therefore, this proposal's objective is to develop a method for rapid expansion of hepatic cells in a novel 3D printed bioscaffold for assembly of a liver organoid for in vivo tissue restoration and ex vivo drug screening. The central hypothesis is that primary hepatic cells seeded in a novel biomaterial scaffold will display similar metabolic function, structure, and biomechanical properties to that of the original liver tissues. The success of this approach will restore liver function following transplantation in a liver-damaged mouse model. The innovative combination of rheological biomaterial tuning, 3D bioprinting, and culture methods that utilize a novel bioscaffold will be applied in pursuit of two specific aims: 1) Engineering an ex vivo model for screening therapeutic drugs targeting hepatocytes through 3D printed bioscaffolds and 2) Development of an implantable hepatic organoid for in vivo tissue restoration to alleviate liver failure in a mouse model. These investigations will establish a platform for novel 3D culture systems for both rigorous in vitro diagnostic screening and for in vivo adoptive transfer approaches to physiologically restore failed liver function. The proposed work is significant as the anticipated results will establish a platform for future investigations utilizing the biomaterial for engineering cell seeded scaffolds to restore tissue function and in pursuit of drug discovery.