INSERM U1052, CNRS UMR-5286, Cancer Research Center of Lyon (CRCL), Lyon, France.
University of Lyon, Université Claude-Bernard (UCBL), Lyon, France.
Gut. 2024 Nov 11;73(12):2012-2022. doi: 10.1136/gutjnl-2023-331396.
Achieving HBV cure will require novel combination therapies of direct-acting antivirals and immunomodulatory agents. In this context, the toll-like receptor 8 (TLR8) agonist selgantolimod (SLGN) has been investigated in preclinical models and clinical trials for chronic hepatitis B (CHB). However, little is known regarding its action on immune effectors within the liver. Our aim was to characterise the transcriptomic changes and intercellular communication events induced by SLGN in the hepatic microenvironment.
We identified -expressing cell types in the human liver using publicly available single-cell RNA-seq data and established a method to isolate Kupffer cells (KCs). We characterised transcriptomic and cytokine KC profiles in response to SLGN. SLGN's indirect effect was evaluated by RNA-seq in hepatocytes treated with SLGN-conditioned media (CM) and quantification of HBV parameters following infection. Pathways mediating SLGN's effect were validated using transcriptomic data from HBV-infected patients.
Hepatic expression takes place in the myeloid compartment. SLGN treatment of KCs upregulated monocyte markers (eg, ) and downregulated genes associated with the KC identity (eg, ). Treatment of hepatocytes with SLGN-CM downregulated and impaired HBV entry. Cotreatment with an interleukin 6-neutralising antibody reverted the HBV entry inhibition.
Our transcriptomic characterisation of SLGN sheds light into the programmes regulating KC activation. Furthermore, in addition to its previously described effect on established HBV infection and adaptive immunity, we show that SLGN impairs HBV entry. Altogether, SLGN may contribute through KCs to remodelling the intrahepatic immune microenvironment and may thus represent an important component of future combinations to cure HBV infection.
实现乙型肝炎病毒 (HBV) 治愈需要新型直接作用抗病毒药物和免疫调节剂联合治疗。在此背景下， Toll 样受体 8 (TLR8) 激动剂 selgantolimod (SLGN) 已在慢性乙型肝炎 (CHB) 的临床前模型和临床试验中进行了研究。然而，对于其在肝脏内免疫效应器中的作用知之甚少。我们的目的是描述 SLGN 在肝内微环境中诱导的转录组变化和细胞间通讯事件。
我们使用公开的单细胞 RNA-seq 数据鉴定了人肝中表达的细胞类型，并建立了分离库普弗细胞 (KC) 的方法。我们对 SLGN 反应的 KC 转录组和细胞因子特征进行了描述。通过用 SLGN 条件培养基 (CM) 处理的肝细胞的 RNA-seq 评估 SLGN 的间接作用，并在感染后定量 HBV 参数。使用 HBV 感染患者的转录组数据验证介导 SLGN 作用的途径。
肝内表达发生在髓系细胞区室中。KC 中 SLGN 处理上调单核细胞标志物（例如），下调与 KC 特征相关的基因（例如）。用 SLGN-CM 处理肝细胞下调并损害 HBV 进入。用白细胞介素 6 中和抗体共同处理可逆转 HBV 进入抑制。
我们对 SLGN 的转录组特征研究揭示了调节 KC 激活的调控程序。此外，除了其先前描述的对已建立的 HBV 感染和适应性免疫的作用外，我们还表明 SLGN 可抑制 HBV 进入。总之，SLGN 可能通过 KC 对肝内免疫微环境进行重塑，并可能因此成为治愈 HBV 感染的未来联合治疗的重要组成部分。
