Department of Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
Hepatology. 2021 Oct;74(4):1825-1844. doi: 10.1002/hep.31857. Epub 2021 Aug 25.
NASH will soon become the leading cause of liver transplantation in the United States and is also associated with increased COVID-19 mortality. Currently, there are no Food and Drug Administration-approved drugs available that slow NASH progression or address NASH liver involvement in COVID-19. Because animal models cannot fully recapitulate human NASH, we hypothesized that stem cells isolated directly from end-stage liver from patients with NASH may address current knowledge gaps in human NASH pathology.
We devised methods that allow the derivation, proliferation, hepatic differentiation, and extensive characterization of bipotent ductal organoids from irreversibly damaged liver from patients with NASH. The transcriptomes of organoids derived from NASH liver, but not healthy liver, show significant up-regulation of proinflammatory and cytochrome p450-related pathways, as well as of known liver fibrosis and tumor markers, with the degree of up-regulation being patient-specific. Functionally, NASH liver organoids exhibit reduced passaging/growth capacity and hallmarks of NASH liver, including decreased albumin production, increased free fatty acid-induced lipid accumulation, increased sensitivity to apoptotic stimuli, and increased cytochrome P450 metabolism. After hepatic differentiation, NASH liver organoids exhibit reduced ability to dedifferentiate back to the biliary state, consistent with the known reduced regenerative ability of NASH livers. Intriguingly, NASH liver organoids also show strongly increased permissiveness to severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) vesicular stomatitis pseudovirus as well as up-regulation of ubiquitin D, a known inhibitor of the antiviral interferon host response.
Expansion of primary liver stem cells/organoids derived directly from irreversibly damaged liver from patients with NASH opens up experimental avenues for personalized disease modeling and drug development that has the potential to slow human NASH progression and to counteract NASH-related SARS-CoV-2 effects.
NASH 将很快成为美国肝移植的主要原因,并且与 COVID-19 死亡率增加有关。目前,尚无获得美国食品和药物管理局批准的药物可减缓 NASH 进展或解决 COVID-19 中 NASH 肝脏受累的问题。由于动物模型无法完全再现人类 NASH,我们假设直接从 NASH 患者的终末期肝脏中分离出的干细胞可能会解决人类 NASH 病理学中的当前知识空白。
我们设计了从不可逆损伤的 NASH 患者肝脏中分离、增殖、肝分化和广泛表征双能胆管类器官的方法。源自 NASH 肝脏的类器官的转录组显示出促炎和细胞色素 P450 相关途径的显着上调,以及已知的肝纤维化和肿瘤标志物的上调,上调程度具有患者特异性。功能上,NASH 肝脏类器官表现出较低的传代/生长能力和 NASH 肝脏的特征,包括白蛋白产生减少、游离脂肪酸诱导的脂质积累增加、对凋亡刺激的敏感性增加以及细胞色素 P450 代谢增加。肝分化后,NASH 肝脏类器官表现出降低的向胆管状态分化的能力,这与 NASH 肝脏已知的再生能力降低一致。有趣的是,NASH 肝脏类器官还表现出对严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 水疱性口炎假病毒的强烈易感性增加以及泛素 D 的上调,泛素 D 是一种已知的抗病毒干扰素宿主反应抑制剂。
直接从不可逆损伤的 NASH 患者肝脏中扩增原代肝干细胞/类器官为个性化疾病建模和药物开发开辟了实验途径,有可能减缓人类 NASH 的进展并对抗 NASH 相关的 SARS-CoV-2 作用。