Zhao Lili, Chen Fuwang, Quitt Oliver, Festag Marvin, Ringelhan Marc, Wisskirchen Karin, Festag Julia, Yakovleva Luidmila, Sureau Camille, Bohne Felix, Aichler Michaela, Bruss Volker, Shevtsov Maxim, van de Klundert Maarten, Momburg Frank, Möhl Britta S, Protzer Ulrike
Institute of Virology, Technical University of Munich/Helmholtz Zentrum München, TUM School of Medicine, Munich, Germany.
Department of Internal Medicine II, University Hospital rechts der Isar, Technical University of Munich, Munich, Germany.
Cell Microbiol. 2021 Dec;23(12):e13399. doi: 10.1111/cmi.13399. Epub 2021 Nov 22.
Hepatitis B virus (HBV) infection is a major health threat causing 880,000 deaths each year. Available therapies control viral replication but do not cure HBV, leaving patients at risk to develop hepatocellular carcinoma. Here, we show that HBV envelope proteins (HBs)-besides their integration into endosomal membranes-become embedded in the plasma membrane where they can be targeted by redirected T-cells. HBs was detected on the surface of HBV-infected cells, in livers of mice replicating HBV and in HBV-induced hepatocellular carcinoma. Staining with HBs-specific recombinant antibody MoMab recognising a conformational epitope indicated that membrane-associated HBs remains correctly folded in HBV-replicating cells in cell culture and in livers of HBV-transgenic mice in vivo. MoMab coated onto superparamagnetic iron oxide nanoparticles allowed to detect membrane-associated HBs after HBV infection by electron microscopy in distinct stretches of the hepatocyte plasma membrane. Last but not least, we demonstrate that HBs located on the cell surface allow therapeutic targeting of HBV-positive cells by T-cells either engrafted with a chimeric antigen receptor or redirected by bispecific, T-cell engager antibodies. TAKE AWAYS: HBs become translocated to the plasma membrane. Novel, recombinant antibody confirmed proper conformation of HBs on the membrane. HBs provide an interesting target by T-cell-based, potentially curative therapies.
乙型肝炎病毒（HBV）感染是一项重大的健康威胁，每年导致88万人死亡。现有的治疗方法可控制病毒复制，但无法治愈HBV，使患者有患肝细胞癌的风险。在此，我们表明，HBV包膜蛋白（HBs）——除了整合到内体膜中外——还会嵌入质膜，在这里它们可以被重定向的T细胞靶向。在HBV感染细胞的表面、复制HBV的小鼠肝脏以及HBV诱导的肝细胞癌中均检测到了HBs。用识别构象表位的HBs特异性重组抗体MoMab染色表明，在细胞培养中的HBV复制细胞以及体内HBV转基因小鼠的肝脏中，与膜相关的HBs保持正确折叠。涂覆在超顺磁性氧化铁纳米颗粒上的MoMab能够在HBV感染后通过电子显微镜在肝细胞质膜的不同区域检测到与膜相关的HBs。最后但同样重要的是，我们证明位于细胞表面的HBs能够通过植入嵌合抗原受体的T细胞或双特异性T细胞衔接抗体重定向的T细胞对HBV阳性细胞进行治疗性靶向。要点：HBs易位至质膜。新型重组抗体证实了膜上HBs的正确构象。HBs为基于T细胞的潜在治愈性疗法提供了一个有吸引力的靶点。
