原发性硬化性胆管炎（Primary sclerosing cholangitis，PSC）是一种伴随肝脏慢性炎症和胆管狭窄的胆道疾病。由于其免疫调节和促进再生的功能，间充质干细胞（Mesenchymal stem cells，MSCs）被用于治疗肝脏疾病。本研究旨在通过Takeda G蛋白偶联受体5（TGR5）受体通路探索人胎盘间充质干细胞（human placental MSCs，hP-MSCs）在PSC中的治疗潜力。本研究收集了PSC患者和健康供体（n = 4）的肝组织进行RNA测序和肝内胆管细胞体外结构的构建。将hP-MSCs通过尾静脉注射到Mdr2-/-、胆管结扎（bile duct ligation，BDL）和3,5-diethoxycarbonyl-1,4-dihydrocollidine（DDC）小鼠模型中，或与体外结构共培养，以确认其对胆管胆囊炎的治疗效果。采用液相色谱/串联质谱（liquid chromatography/tandem mass spectrometry，LC-MS/MS）分析胆汁酸代谢谱的变化。与健康对照组相比，PSC患者的肝组织和肝内胆管细胞外结构特征表现为炎症和胆汁淤积，并明显下调胆汁酸受体TGR5的表达。hP-MSC治疗显著减轻了Mdr2-/-、BDL和DDC模型小鼠的炎症、胆汁淤积和纤维化。通过激活磷脂酰肌醇3激酶/外源性信号调节激酶途径，hP-MSC治疗促进了胆管细胞增殖，并通过调节TGR5和Pellino3的结合影响下游核因子κB的转录，从而影响了胆管细胞炎性表型的发生。版权所有© 2023 Qigu Yao等。

Primary sclerosing cholangitis (PSC) is a biliary disease accompanied by chronic inflammation of the liver and biliary stricture. Mesenchymal stem cells (MSCs) are used to treat liver diseases because of their immune regulation and regeneration-promoting functions. This study was performed to explore the therapeutic potential of human placental MSCs (hP-MSCs) in PSC through the Takeda G protein-coupled receptor 5 (TGR5) receptor pathway. Liver tissues were collected from patients with PSC and healthy donors (n = 4) for RNA sequencing and intrahepatic cholangiocyte organoid construction. hP-MSCs were injected via the tail vein into Mdr2-/-, bile duct ligation (BDL), and 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) mouse models or co-cultured with organoids to confirm their therapeutic effect on biliary cholangitis. Changes in bile acid metabolic profile were analyzed by liquid chromatography/tandem mass spectrometry (LC-MS/MS). Compared with healthy controls, liver tissues and intrahepatic cholangiocyte organoids from PSC patients were characterized by inflammation and cholestasis, and marked downregulation of bile acid receptor TGR5 expression. hP-MSC treatment apparently reduced the inflammation, cholestasis, and fibrosis in Mdr2-/-, BDL, and DDC model mice. By activating the phosphatidylinositol 3 kinase/extracellular signal-regulated protein kinase pathway, hP-MSC treatment promoted the proliferation of cholangiocytes, and affected the transcription of downstream nuclear factor κB through regulation of the binding of TGR5 and Pellino3, thereby affecting the cholangiocyte inflammatory phenotype.Copyright © 2023 Qigu Yao et al.