背景:胆道闭锁(BA)是一种以导管反应为主要致病特征的新生儿纤维炎性胆管病变,可预测患者的生存率。粘膜相关的不变T(MAIT)细胞在人类肝脏中富集,并在肝脏疾病中发挥多种作用。我们旨在研究MAIT细胞在BA中的功能。
方法:首先,我们分析了肝脏MAIT细胞与临床参数(存活率,丙氨酸转氨酶,胆红素,组织学炎症和纤维化)在两个公共BA患者队列中(美国和中国)。生存数据和其他临床参数采用Kaplan-Meier生存分析和Spearman相关分析。分别。接下来,我们从BA和对照患者的肝脏样本或外周血中获取大量RNA测序,流式细胞术分析,MAIT细胞的免疫固定和功能实验。最后,我们建立了两个体外共培养系统,一种是恒河猴轮状病毒(RRV)感染的共培养系统,用于模拟人BA的免疫功能障碍,该系统通过单细胞RNA测序进行了验证,另一种是由胆道类器官组成的多细胞系统,LX-2和MAIT细胞评价MAIT细胞对导管反响的感化。
结果:BA肝脏MAIT细胞与低存活率和导管反应呈正相关。此外,肝脏MAIT细胞被激活,以T细胞受体(TCR)依赖性方式表现出伤口愈合特征和高表达的生长因子双调蛋白(AREG)。AREG的拮抗作用消除了BAMAIT细胞对胆管细胞和胆道类器官的增殖作用。RRV感染的共培养系统,概述了人类BA的免疫功能障碍,揭示了RRV引发的MAIT细胞通过AREG促进胆管细胞增殖,并进一步诱导多细胞系统的炎症和纤维化。
结论:MAIT细胞表现出依赖于TCR信号的伤口愈合特征,并通过AREG促进导管反应,这与晚期纤维化有关,并预示着BA的低生存率。
背景:这项工作得到了国家自然科学基金资助(82001589和92168108),国家重点研发计划(2023YFA1801600)和广东省基础与应用基础研究基金(2020A1515110921)。
BACKGROUND: Biliary atresia (BA) is a neonatal fibro-inflammatory cholangiopathy with ductular reaction as a key pathogenic feature predicting poor survival. Mucosal-associated invariant T (MAIT) cells are enriched in human liver and display multiple roles in liver diseases. We aimed to investigate the function of MAIT cells in BA.
METHODS: First, we analyzed correlations between liver MAIT cell and clinical parameters (survival, alanine transaminase, bilirubin, histological inflammation and fibrosis) in two public cohorts of patients with BA (US and China). Kaplan-Meier survival analysis and spearman correlation analysis were employed for survival data and other clinical parameters, respectively. Next, we obtained liver samples or peripheral blood from BA and control patients for bulk RNA sequencing, flow cytometry analysis, immunostaning and functional experiments of MAIT cells. Finally, we established two in vitro co-culture systems, one is the rhesus rotavirus (RRV) infected co-culture system to model immune dysfunction of human BA which was validated by single cell RNA sequencing and the other is a multicellular system composed of biliary organoids, LX-2 and MAIT cells to evaluate the role of MAIT cells on ductular reaction.
RESULTS: Liver MAIT cells in BA were positively associated with low survival and ductular reaction. Moreover, liver MAIT cells were activated, exhibited a wound healing signature and highly expressed growth factor Amphiregulin (AREG) in a T cell receptor (TCR)-dependent manner. Antagonism of AREG abrogated the proliferative effect of BA MAIT cells on both cholangiocytes and biliary organoids. A RRV infected co-culture system, recapitulated immune dysfunction of human BA, disclosed that RRV-primed MAIT cells promoted cholangiocyte proliferation via AREG, and further induced inflammation and fibrosis in the multicellular system.
CONCLUSIONS: MAIT cells exhibit a wound healing signature depending on TCR signaling and promote ductular reaction via AREG, which is associated with advanced fibrosis and predictive of low survival in BA.
BACKGROUND: This work was funded by National Natural Science Foundation of China grant (82001589 and 92168108), National Key R&D Program of China (2023YFA1801600) and by Basic and Applied Basic Research Foundation of Guangdong (2020A1515110921).