Engineering microniches within liver organoid systems to identify metabolic signalling functions underlying liver regeneration.

与其他内脏器官不同的是，肝脏在受损后能够进行多轮再生。最近，被称为类器官的3D细胞聚集体已经被描述为可以在体外模拟肝脏再生。再生信号如何整合细胞内和细胞外的信号，包括细胞的能量平衡，来引导成体干细胞退出静止，增殖和分化尚不清楚。该项目将使用来自小鼠和人类肝脏的类器官来阐明肝脏再生背后的代谢信号功能。代谢组学的进展揭示了代谢底物和副产物通过糖酵解和氧化磷酸化的平衡调节干细胞命运的多种系统。类器官提供了有形的系统，在受控环境中评估分化过程中特定代谢信号通路的活性和作用，而不受全身代谢或其他信号信号的影响。本项目旨在；1)使用完全化学定义的培养基和合成水凝胶作为三维支架，获得肝脏类器官培养的完全代谢控制。2)表征再生过程中代谢状态的变化。3)通过代谢扰动研究再生过程中代谢状态的功能相关性。通过改变氧和营养物质的可用性、代谢抑制剂的施用以及通过限制速率的糖酵解酶的遗传操作来实现扰动。更深入地了解肝脏再生是基础生物学的一个关键兴趣，最终可能有助于获得慢性肝损伤患者的治疗方法。重要的是，了解肝祖细胞的代谢需求将导致更好地概括体外功能肝脏模型的方案，用于个性化医疗，药物发现和毒性研究等治疗目的。

Strikingly and in contrast to other internal organs, when damaged the liver is capable of multiple rounds of regeneration. Recently, 3D cell aggregates, known as organoids, have been described that can model liver regeneration in vitro. How regenerative signals integrate intra- and extra-cellular cues, including the energy balance of the cell, to guide adult stem cells to exit quiescence, proliferate and differentiate is not clear. This project will use organoids derived from mouse and human liver to elucidate the metabolic signalling functions underlying liver regeneration.Advances in metabolomics have revealed multiple systems in which metabolic substrates and by products regulate stem cell fate via a balance of glycolysis and oxidative phosphorylation. Organoids provide tangible systems in which to assess the activity and effect of specific metabolic signalling pathways during differentiation in a controlled environment separate from the influence of whole-body metabolism or other signalling cues.This project aims to; 1) Gain full metabolic control of liver organoid culture using fully chemically-defined media and a synthetic hydrogel as 3D scaffold. 2) Characterise changes in metabolic state during regeneration. 3) Investigate the functional relevance of metabolic state during regeneration through metabolic perturbations. Perturbations will be achieved by alterations to oxygen and nutrient availability, administration of metabolic inhibitors, and through genetic manipulation of rate-limiting glycolytic enzymes.Greater insight into liver regeneration is a key interest for basic biology and ultimately may help derive therapies for patients suffering from chronic liver injury. Importantly, understanding the metabolic requirements of liver progenitors will lead to protocols to better recapitulate functional liver models in vitro for therapeutic purposes such as personalised medicine, drug discovery and toxicity studies.