Modelling liver disease requires in vitro systems that replicate disease progression^1,2. Current tissue-derived organoids fail to reproduce the complex cellular composition and tissue architecture observed in vivo³. Here, we describe a multicellular organoid system composed of adult hepatocytes, cholangiocytes and mesenchymal cells that recapitulates the architecture of the liver periportal region and, when manipulated, models aspects of cholestatic injury and biliary fibrosis. We first generate reproducible hepatocyte organoids with functional bile canaliculi network that retain morphological features of in vivo tissue. By combining these with cholangiocytes and portal fibroblasts, we generate assembloids that mimic the cellular interactions of the periportal region. Assembloids are functional, consistently draining bile from bile canaliculi into the bile duct. Strikingly, manipulating the relative number of portal mesenchymal cells is sufficient to induce a fibrotic-like state, independently of an immune compartment. By generating chimeric assembloids of mutant and wild-type cells, or after gene knockdown, we show proof-of-concept that our system is amenable to investigating gene function and cell-autonomous mechanisms. Taken together, we demonstrate that liver assembloids represent a suitable in vitro system to study bile canaliculi formation, bile drainage, and how different cell types contribute to cholestatic disease and biliary fibrosis, in an all-in-one model.

对肝病进行建模需要复制疾病进展的体外系统 ^1,2。目前的组织来源类器官无法再现在体内观察到的复杂细胞组成和组织结构 ³。在这里，我们描述了一个由成年肝细胞、胆管细胞和间充质细胞组成的多细胞类器官系统，该系统概括了肝脏门静脉周围区域的结构，并且在作时，模拟胆汁淤积损伤和胆汁纤维化的各个方面。我们首先生成具有功能性胆小管网络的可重复肝细胞类器官，该网络保留了体内组织的形态特征。通过将它们与胆管细胞和门静脉成纤维细胞相结合，我们生成了模拟门静脉周围区域细胞相互作用的组装体。集合体具有功能性，持续将胆汁从胆管排入胆管。引人注目的是，纵门静脉间充质细胞的相对数量足以诱导纤维化样状态，独立于免疫区室。通过生成突变型和野生型细胞的嵌合组装体，或在基因敲低后，我们证明了我们的系统适合研究基因功能和细胞自主机制的概念验证。综上所述，我们证明了肝脏组装体代表了一种合适的体外系统，可用于在一体化模型中研究胆汁小管形成、胆汁引流以及不同细胞类型如何导致胆汁淤积性疾病和胆汁纤维化。