Macrophage Cell Subset Specific Biomarkers for Disease Prognosis in Biliary Atresia

项目总结： 胆道闭锁(BA)是一种婴儿期的胆汁淤积性肝病，是儿童肝脏的主要病因。 移植。虽然有证据支持异常免疫反应在BA的发病机制中所起的作用，但 疾病的确切机制仍不清楚。科学知识的这种鸿沟限制了免疫的鉴定。 诊断时用生物标记物对患者预后进行分层。虽然巨噬细胞(M)此前曾被牵连 在人类和小鼠BA中，M-本质上是异质性的，并且持续进行所需的致病亚群 肝脏损伤尚未确定。克服这一科学知识差距将确定特定于BA的 致病性M-亚群，并导致预测患者预后的新的细胞亚群特异性生物标记物。 我们首次在儿童胆汁淤积性肝病中发现了3个新的肝脏M-亚群。 利用单细胞测序能力进行有别于未患病M-rna的肝移植 (scRNA-seq)。我们将这些M亚集定义为脂质相关的M(高表达的参与 脂代谢)、类单核细胞M(也在单核细胞中发现的基因表达)和适应性M (对涉及淋巴细胞激活的基因进行浓缩)。此外，类单核细胞和适应性M-亚群 与Luo等人建立的预后不良征象呈正相关，提示这些 亚群可能推动纤维化和CD8+T细胞的激活，这与疾病的结局有关。因此，我们 假设血清细胞因子网络驱动M-极化向致病单核细胞样和 适应性M亚集；诊断时组织学增加的这些M亚集的数量将是 与糟糕的结果相关。 为了研究这一假说，我们将：1)确定脂质相关的、单核细胞样的和 人类BA诊断时的适应性M-与3个月内黄疸清除定义的预后相关 和2)在血清中确定M特异性细胞因子网络，这些细胞因子与 预后和组织学表现。这一创新的研究计划应用了先前scRNA-seq的研究结果。 对儿童标本进行分析以鉴定M-亚群特异性组织学和血清 在诊断时预测预后的生物标志物。这项研究的发现将促进对患有糖尿病的患者的护理 BA，并允许在KPE时改善预后咨询。

PROJECT SUMMARY: Biliary atresia (BA) is a cholestatic liver disease of infancy that is the leading cause of pediatric liver transplantation. While evidence supports a role for an aberrant immune response in the pathogenesis of BA, the exact mechanism of disease remains unknown. This gap in scientific knowledge limits identification of immune biomarkers at diagnosis to stratify patient prognosis. While macrophages (M) have previously been implicated in both human and murine BA, M are heterogeneous by nature and the pathogenic subsets required for ongoing hepatic injury have not been identified. Overcoming this gap in scientific knowledge will identify the BA-specific pathogenic M subsets and lead to novel cell-subset specific biomarkers predictive of patient prognosis. We have been the first to identify 3 novel hepatic M subsets in pediatric cholestatic liver disease at the time of liver transplant that are distinct from non-diseased M by leveraging the ability of single cell RNA-sequencing (scRNA-seq). We have defined these M subsets as lipid-associated M (high expression of genes involved in lipid metabolism), monocyte-like M (expression of genes also identified in monocytes), and adaptive M (enrichment for genes involved in lymphocyte activation). Furthermore, monocyte-like and adaptive M subsets positively correlate with the poor prognostic signature at diagnosis established by Luo et al suggesting these subsets may drive fibrosis and activation of CD8-positive T cells implicated in disease outcome. We thereby hypothesize that serum cytokine networks drive M polarization towards pathogenic monocyte-like and adaptive M subsets; increased numbers of these M subsets by histology at diagnosis will be associated with poor outcome. To investigative this hypothesis we will: 1) determine if the numbers of lipid-associated, monocyte-like, and adaptive M at diagnosis in human BA correlate with outcome as defined by clearance of jaundice by 3 months post-Kasai Portoenterostomy (KPE), and 2) define M-specific cytokine networks in serum that correlate with prognosis and histologic findings. This innovative research plan applies findings from previous scRNA-seq analysis to human samples available from ChiLDReN to identify M-subset specific histologic and serum biomarkers for prognosis at the time of diagnosis. Findings from the study will advance the care of patients with BA and allow for improved prognostic counseling at the time of KPE.