Bockmann Jan-Hendrik, Allweiss Lena, Volmari Annika, da Fonseca Araújo David, Kohsar Matin, Hyrina Anastasia, Kah Janine, Song Zhijuan, Chan Josolyn, Giersch Katja, Volz Tassilo, Lütgehetmann Marc, Wallin Jeffrey J, Manuilov Dmitry, Holdorf Meghan M, Fletcher Simon P, Lohse Ansgar W, Bertoletti Antonio, Schulze Zur Wiesch Julian, Dandri Maura
Department of Internal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel-Riems site, Germany.
JHEP Rep. 2024 Nov 14;7(3):101273. doi: 10.1016/j.jhepr.2024.101273. eCollection 2025 Mar.
BACKGROUND & AIMS: The role of hepatocytes in producing chemokines and triggering liver inflammation and damage in chronic hepatitis D (CHD) is not fully understood. Herein, we investigated the contribution of primary human hepatocytes (PHHs) infected with HDV in triggering inflammation by producing the chemokines CXCL9-11.
We performed quantitative PCR, RNA hybridisation, activation-induced marker (AIM) assays, and FACS analysis to investigate the CXCR3/CXCL9-11 receptor/ligand axis of T cells in peripheral blood and livers from patients with chronic hepatitis B (n = 27 and 18, respectively) and CHD (n = 20 and 18, respectively). Chemokine expression was investigated in cultured HDV-infected PHHs and in livers of HBV- or HBV/HDV-infected humanised mice in the presence or absence of adoptively transferred human immune cells (n = 35 in total).
In patient and chimeric mouse livers, higher expression levels of CXCL9-11 were found in an HBV/HDV-coinfected . HBV-mono-infected setting. Similarly, high levels of CXCL9-11 were observed in HDV-infected PHHs . Analysis by RNA hybridisation on patient livers revealed that HDV-infected hepatocytes were a significant contributor to the chemokine expression. The corresponding chemokine receptor CXCR3 was found upregulated specifically on peripheral bulk CD4 T cells of patients with CHD. CXCR3 upregulation was unspecific and was not detected on HDAg- or HBsAg-specific CD4 T cells by activation-induced marker assay. Lastly, adoptive transfer of human T cells in humanised mice led to recruitment of non-HBV/HDV-specific CD4+ T cells only in the setting of HBV/HDV coinfection, but not in HBV-mono-infected mice.
HDV infection upregulated the intrahepatic expression of the CXCL9-11/CXCR3 receptor/ligand axis. Higher amounts of HBV/HDV-unspecific CD4 T cells expressing CXCR3 may contribute to the aggravated liver inflammation frequently observed in patients with CHD.
Chronic hepatitis D (CHD) causes the most severe form of viral hepatitis, and treatment options are still limited; therefore, a more precise understanding of CHD immunopathology is needed. In this study, we demonstrated that HDV infection triggers CXCL9-11 expression in hepatocytes and liver infiltration of CXCR3-expressing CD4 T cells in preclinical models as well as patient biopsies. Because recruitment of Th1-polarised CD4 T cells to the liver has been also described for other severe liver diseases, such as autoimmune hepatitis, it may represent an important mechanism of aggravating liver diseases. The data of this study set hereby the basis for future studies analysing phenotype and function of intrahepatic T cells in CHD.
肝细胞在慢性丁型肝炎（CHD）中产生趋化因子以及引发肝脏炎症和损伤方面的作用尚未完全明确。在此，我们研究了感染HDV的原代人肝细胞（PHH）通过产生趋化因子CXCL9 - 11在引发炎症中的作用。
我们进行了定量PCR、RNA杂交、激活诱导标志物（AIM）分析和流式细胞术分析，以研究慢性乙型肝炎患者（分别为n = 27和18例）和CHD患者（分别为n = 20和18例）外周血和肝脏中T细胞的CXCR3/CXCL9 - 11受体/配体轴。在有或没有过继转移的人免疫细胞的情况下（总共n = 35），研究了培养的感染HDV的PHH以及HBV或HBV/HDV感染的人源化小鼠肝脏中的趋化因子表达。
在患者和嵌合小鼠肝脏中，在HBV/HDV合并感染的情况下发现CXCL9 - 11的表达水平高于HBV单一感染的情况。同样，在感染HDV的PHH中观察到高水平的CXCL9 - 11。通过对患者肝脏进行RNA杂交分析发现，感染HDV的肝细胞是趋化因子表达的重要贡献者。发现相应的趋化因子受体CXCR3在CHD患者的外周总CD4 T细胞上特异性上调。通过激活诱导标志物分析，CXCR3上调是非特异性的，在HDAg或HBsAg特异性CD4 T细胞上未检测到。最后，在人源化小鼠中过继转移人T细胞仅在HBV/HDV合并感染的情况下导致非HBV/HDV特异性CD4 + T细胞的募集，而在HBV单一感染的小鼠中未出现。
HDV感染上调了CXCL9 - 11/CXCR3受体/配体轴的肝内表达。表达CXCR3的大量HBV/HDV非特异性CD4 T细胞可能导致CHD患者中经常观察到的肝脏炎症加重。
慢性丁型肝炎（CHD）导致最严重形式的病毒性肝炎，治疗选择仍然有限；因此，需要更精确地了解CHD免疫病理学。在本研究中，我们证明在临床前模型以及患者活检中，HDV感染触发肝细胞中CXCL9 - 11的表达以及表达CXCR3的CD4 T细胞的肝脏浸润。因为在其他严重肝脏疾病如自身免疫性肝炎中也描述了Th1极化的CD4 T细胞向肝脏的募集，它可能代表了加重肝脏疾病的重要机制。本研究的数据为未来分析CHD中肝内T细胞的表型和功能的研究奠定了基础。
