Project description:Hepatitis E virus (HEV) infection, one of the most common forms of hepatitis worldwide, is often associated with extrahepatic, particularly renal, manifestations. However, the underlying mechanisms are incompletely understood. Here, we report the development of a de novo immune complex-mediated glomerulonephritis (GN) in a kidney transplant recipient with chronic hepatitis E. Applying immunostaining, electron microscopy, and mass spectrometry after laser-capture microdissection, we show that GN developed in parallel with increasing glomerular deposition of a non-infectious, genome-free and non-glycosylated HEV open reading frame 2 (ORF2) capsid protein. No productive HEV infection of kidney cells is detected. Patients with acute hepatitis E display similar but less pronounced deposits. Our results establish a link between the production of HEV ORF2 protein and the development of hepatitis E-associated GN. The formation of glomerular IgG-HEV ORF2 immune complexes discovered here provides a mechanistic explanation of how the actually hepatotropic HEV can cause variable renal manifestations. These findings directly provide a tool for etiology-based diagnosis of hepatitis E-associated GN as a distinct entity and suggest therapeutic implications.
Project description:Hepatitis E virus (HEV) is an important causative pathogen of acute hepatitis. Because of the absence of an in vitro culture system for HEV, research has been greatly impeded. And interaction between HEV and host cells was mainly studied by tansfection/transinfection system, such as Adeno virus transinfection system. We developed an in vitro culture system for HEV in PLC/PRF/5 cells. With this in vitro culture system, we studied the gene expression profile change by HEV infection. Using a microarray assay, we analysed genes of PLC/PRF/5 cells, whose transcription level could be changed by HEV infection. Five flasks of PLC/PRF/5 cells inoculated with HEV were used as test sample, and five flasks inoculated with serum-free DMEM/199 medium were used as control samples. Both test and control flasks were cultured under the same conditions. Sixty days after inoculation, the test and control flasks was resolved with Trizol and analysed with Affymetrix HG-U133 Plus 2 array.
Project description:Hepatitis E virus (HEV) is an important causative pathogen of acute hepatitis. Because of the absence of an in vitro culture system for HEV, research has been greatly impeded. And interaction between HEV and host cells was mainly studied by tansfection/transinfection system, such as Adeno virus transinfection system. We developed an in vitro culture system for HEV in PLC/PRF/5 cells. With this in vitro culture system, we studied the gene expression profile change by HEV infection. Using a microarray assay, we analysed genes of PLC/PRF/5 cells, whose transcription level could be changed by HEV infection.
Project description:Background: Hepatitis E Virus (HEV) is a new causative agent of chronic hepatitis in solid organ transplant recipients in Europe. Factors associated with the occurrence and persistence of chronic HEV infection remain largely unknown but chronic evolution seems to be the consequence of hostM-bM-^@M-^Ys immunological factors rather than of viral factors. Method: In a prospective case-control study, we have determined in whole blood of chronically HEV-infected kidney-transplant recipients the host response using microarray technology. Results: Chronically HEV-infected kidney-transplant recipients exhibited a specific transcriptional program, in which interferon effectors were prominent. The intensity of expression of each signatureM-bM-^@M-^Ys gene was significantly lower in patients who were subsequently cleared of HEV than in patients who were not. Furthermore, in patients who were cleared of HEV, a higher expression of these genes was associated with a longer delay until HEV clearance. Conclusions: The specific transcriptional program determined in chronically HEV-infected kidney-transplant recipients suggests an activation of type I interferon response. Intensity of interferon-stimulated genes expression could be useful to forecast the outcome of infection. High expression of interferon-stimulated genes could signify a dysregulation in the interferon response that might favour the persistence of the HEV infection. TrialM-bM-^@M-^Ys registration number: NCT01090232; RegistryM-bM-^@M-^Ys URL: http://clinicaltrials.gov/ct2/show/study/NCT01090232?term=kidney+transplant+recipients&cntry1=EU%3AFR&rank=2 Total RNA was extracted from whole-blood sample or monocytes of kidney-transplant patients with or without chronic hepatitis E (CHE) infection. Control patients were matched up with CHE patients for age, sex, time since kidney transplant and immunosuppressive treatment.
Project description:Hepatitis E virus (HEV) is a major cause of acute hepatitis and mainly transmitted faecal-orally. HEV particles present in faeces are naked (nHEV), whereas those found in the blood are enveloped (eHEV) with a cell-derived lipid membrane. Despite its global health impact, the cellular life cycle of HEV remains poorly understood, particularly regarding the mechanisms of viral entry into host cells. To address this knowledge gap, we have developed a high content RNA-FISH-based imaging assay that allows, for the first time, the investigation of the entry pathways of both naked and enveloped HEV particles. Surprisingly, we obtained compelling evidence that integrin α3, previously implicated in naked HEV cell entry, is not expressed in various HEV-permissive cells. Instead, we have identified integrin β1 (ITGB1) as the key player in pairing with exchangeable α-integrins to mediate naked HEV cell entry. Our results indicate that the interaction with ITGB1 facilitates naked HEV entry through the recycling endosome. In contrast, enveloped HEV particles do not interact with ITGB1 and rather use the classical endocytic route via the early endosome. Importantly, both forms of HEV require endosomal acidification and proteolytic cleavage by lysosomal cathepsins, which ultimately results in delivery of the HEV genome to the cytoplasm.
Project description:Infection with hepatitis E virus (HEV) represents a global problem, with over 20 million people infected annually. No specific antiviral drugs are available for treating HEV infection, necessitating the development of novel targeted therapeutics. Here, we report that the N-methyl-D-aspartate receptor (NMDAR) antagonist ifenprodil, a clinically approved drug used to treat idiopathic pulmonary fibrosis (IPF), is an HEV inhibitor in liver-derived cells. In vitro investigation demonstrates that ifenprodil suppresses viral protein expression in a dose-dependent manner in human hepatoma cells by inhibiting early stages of viral infection. We also found that ifenprodil modulates host cell intrinsic biological processes distinct from virus-induced innate immunity, inhibiting HEV RNA accumulation in primary human hepatocytes. Finally, the inhibitory effect of ifenprodil in vivo was also tested in rabbits challenged with the HEV-3ra CHN-BJ-R14 strain. Fecal virus shedding was below the limit of detection in two animals for both ribavirin-treated and ifenprodil-treated rabbits compared to vehicle-treated control animals. Our data demonstrate that ifenprodil is an effective anti-HEV compound with potential as a therapeutic candidate for the treatment of HEV infection.
Project description:The liver, and more precisely hepatocytes, can be infected by several viruses such as hepatitis B (HBV), hepatitis D (HDV), hepatitis C (HCV), hepatitis E (HEV) viruses, with chronic infection leading to end-stage liver diseases. Since no in vitro model allowing multi-infections with the four viruses is reported, limited data are available on the interplay between those viruses as well as on the potential cross-reactivity of antivirals in multi-infection cases. Here we showed that HuH7.5-NTCP cells can be partially differentiated into hepatocyte-like cells and genuinely replicate HBV, HDV, HCV and HEV for at least 4 weeks after mono or multiple infections. Additionally, we recapitulated the effect of known antivirals and found that FXR-agonists, also strongly inhibited HEV replication. Using HEV infected HuHep mice, we confirmed the antiviral effect of Vonafexor, the FXR agonist clinical candidate currently tested against HBV and HDV, highlighting FXR-ligands as potential broad acting antivirals. Here, we set-up the first in vitro model allowing multi-infections with hepatitis viruses that can be used for broad drug screening.
Project description:Lipid droplets (LDs) are dynamic organelles mediating lipid metabolism and diverse cellular processes. However, the interplay between hepatocyte LDs and hepatitis E remains poorly understood. Using targeted lipidomics and lipid profiling, we reveal in cellular and rodent models that hepatitis E virus (HEV) infection substantially increases hepatocyte LD biogenesis. Mechanistically, HEV pORF3 is a key LD biogenesis inducer and an essential factor for viral infectivity in vivo. pORF3 formed a unique LD organelle through its liquid-liquid phase-separation (LLPS) property, associating with enhancing cholesterol anabolic pathways, thereby facilitating the synthesis of triglycerides and cholesterol esters. Accordingly, deleting ORF3 or inhibiting LD biogenesis with LD-lowering agent atorvastatin substantially suppressed HEV infection in vivo. These findings position LDs as critical hubs for HEV infection, reveal lipid biogenesis as a crucial function of HEV infectivity, and suggest alternative strategies for HEV intervention.