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，并导致超过70，000人死亡 每年在美国。部分由于人口老龄化，肝病预计将增加 在接下来的二十年里，对更有效的治疗方法的需求增加， 提高了移植的成功率。不幸的是，没有有效的治疗方法来遏制病理 而且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。然而，一个可行的解决方案是使用模型肝脏 准确模拟体内肝组织的生物力学和生物化学功能的系统。 此外，在维持功能的同时扩增受体自体肝细胞的替代方法将 作为产生用于移植的肝脏系统的有效方法。然而，虽然用于体内的肝脏模型 尽管已经尝试过使用，但是还没有人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减轻接受者的肝衰竭。我的实验室 最近证明了这种方法的成功，我们已经建立了有效的体外3D肝细胞 培养体系快速扩张。此外，我们的初步工作表明， 使用我们创新的内部设计的3D支架系统进行体内过继植入。因此，我们认为， 该提案的目的是开发一种在新型3D打印机中快速扩增肝细胞的方法。 本发明涉及用于组装肝类器官的生物支架，所述肝类器官用于体内组织修复和离体药物筛选。的 中心假设是，接种在新型生物材料支架中的原代肝细胞将显示类似的 代谢功能、结构和生物力学性质与原始肝组织的相似。的成功 该方法将在肝损伤小鼠模型中移植后恢复肝功能。的 流变生物材料调整，3D生物打印和培养方法的创新组合， 新型生物支架将用于追求两个特定目标：1）工程化用于筛选的离体模型 通过3D打印生物支架靶向肝细胞的治疗药物和2）开发可植入的 用于体内组织修复以减轻小鼠模型中肝衰竭肝类器官。这些调查 将建立一个新的3D培养系统的平台，用于严格的体外诊断筛选和体内培养。 通过体内过继转移方法在生理上恢复衰竭的肝功能。拟议的工作是 重要的是，预期的结果将为未来的研究建立一个平台，利用生物材料， 工程细胞种植支架，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.