Background & Aims: Biliary Atresia (BA) is a devastating fibro-inflammatory biliary disease that is the leading indication for pediatric liver transplants worldwide. Although cholangiocytes are the primary target cells, the pathogenic mechanisms involving cholangiocytes remain elusive. Here, we aimed to characterize the pathogenic role of cholangiocytes in BA. Approach & Results: Integration of single-cell RNA sequencing of 12 liver tissues (from 9 BA and 3 controls) and the spatial transcriptome of another four liver sections (from 2 BA and 2 controls) provided a comprehensive spatial liver cell atlas of BA. In particular, we identified a cholangiocyte-enriched spatial niche with infiltration of activated hepatic stellate cells, activated portal fibroblasts, macrovascular endothelial cells and TREM2+ macrophages that were elevated in the portal triad of BA. This niche was positively correlated with bile duct profiles, liver fibrosis and poor survival in two independent cohorts of patients with BA. Using integrative bioinformatics analyses to mine the cell-cell communication and regulatory network in BA cholangiocytes, we uncovered the fibro-inflammatory phenotype of cholangiocytes with TNFSF12-TNFRSF12A as a significant signal. Genetic ablation or blockade of TNFRSF12A suppresses liver injury, inflammation, and bile duct profiles in a mouse model of disease. Using human biliary organoids, we revealed that BA organoids expressed higher levels of CCL2 in response to TNFSF12 stimulation and promoted monocyte chemotaxis via the CCL2-CCR2 axis. Conclusions: Pathogenic cholangiocytes enriched niche identifies TNFRSF12A as a potential therapeutic target for BA.

中文翻译：

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综合单细胞和空间转录组分析确定了致病性胆管细胞生态位和 TNFRSF12A 作为胆道闭锁的治疗靶点


背景与目标：胆道闭锁（BA）是一种破坏性纤维炎症性胆道疾病，是全球儿科肝移植的主要适应症。尽管胆管细胞是主要靶细胞，但涉及胆管细胞的致病机制仍然难以捉摸。在这里，我们的目的是表征胆管细胞在 BA 中的致病作用。方法和结果：整合 12 个肝组织（来自 9 个 BA 和 3 个对照）的单细胞 RNA 测序和另外 4 个肝脏切片（来自 2 个 BA 和 2 个对照）的空间转录组，提供了 BA 的综合空间肝细胞图谱。特别是，我们发现了一个富含胆管细胞的空间生态位，其中有活化的肝星状细胞、活化的门脉成纤维细胞、大血管内皮细胞和 TREM2+ 巨噬细胞的浸润，这些细胞在 BA 的门脉三联征中升高。在两个独立的 BA 患者队列中，这一生态位与胆管特征、肝纤维化和不良生存率呈正相关。利用综合生物信息学分析挖掘 BA 胆管细胞中的细胞间通讯和调节网络，我们发现了胆管细胞的纤维炎症表型，其中 TNFSF12-TNFRSF12A 作为重要信号。 TNFRSF12A 的基因消除或阻断可抑制小鼠疾病模型中的肝损伤、炎症和胆管特征。使用人胆道类器官，我们发现 BA 类器官响应 TNFSF12 刺激而表达较高水平的 CCL2，并通过 CCL2-CCR2 轴促进单核细胞趋化性。结论：致病性胆管细胞富集的生态位将 TNFRSF12A 确定为 BA 的潜在治疗靶点。