Life cycle and morphogenesis of the hepatitis E virus

Effect and mechanism of C-terminal cysteine on the properties of HEV p222 protein

Preliminary investigations have demonstrated that the cysteines located at the C-terminus of HEV ORF2 protein exhibits disulfide bonding capability during virus-like particles (VLPs) assembly. However, the effect and mechanism underlying the pairing of disulfide bonds formed by C627, C630, and C638 remains unclear. The p222 protein encompasses C-terminus and serves as a representative of HEV ORF2 to investigate the specific impacts of C627, C630, and C638. The three cysteines were subjected to site-directed mutagenesis and expressed in prokaryotes; Both the mutated proteins and p222 underwent polymerization except for p222A; Surprisingly, only p222 was observed as abundant spherical particles under transmission electron microscope (TEM); Stability and immunogenicity of the p222 exhibited higher than other mutated proteins; LC/MS/MS analysis identified four disulfide bonds in the p222. The novel findings suggest that the three cysteines contribute to structural and functional properties of ORF2 protein, highlighting the indispensability of each cysteine.

Identification of interferon-stimulated genes with modulated expression during hepatitis E virus infection in pig liver tissues and human HepaRG cells

Introduction

Hepatitis E virus (HEV) is a common cause of enterically transmitted acute hepatitis worldwide. The virus is transmitted by the fecal-oral route via the consumption of contaminated water supplies and is also a zoonotic foodborne pathogen. Swine are the main reservoir of zoonotic HEV. In humans, HEV infection is usually asymptomatic or causes acute hepatitis that is self-limited. However, fulminant hepatic failure and chronic cases of HEV infection can occur in some patients. In contrast, HEV infection in pigs remains asymptomatic, although the virus replicates efficiently, suggesting that swine are able to control the virus pathogenesis. Upon viral infection, IFN is secreted and activates cellular pathways leading to the expression of many IFN-stimulated genes (ISGs). ISGs can restrict the replication of specific viruses and establish an antiviral state within infected and neighboring cells.

Methods

In this study, we used PCR arrays to determine the expression level of up to 168 ISGs and other IFN-related genes in the liver tissues of pigs infected with zoonotic HEV-3c and HEV-3f and in human bipotent liver HepaRG cells persistently infected with HEV-3f.

Results and discussion

The expression of 12 and 25 ISGs was found to be up-regulated in infected swine livers and HepaRG cells, respectively. The expression of CXCL10, IFIT2, MX2, OASL and OAS2 was up-regulated in both species. Increased expression of IFI16 mRNA was also found in swine liver tissues. This study contributes to the identification of potential ISGs that could play a role in the control or persistence of HEV infection.

Discovery of Hepatitis E and Its Impact on Global Health: A Journey of 44 Years about an Incredible Human-Interest Story

The story of the discovery of hepatitis E originated in the late 1970s with my extreme belief that there was a hidden saga in the relationship between jaundice and pregnancy in developing countries and the opportunity for a massive epidemic of viral hepatitis, which hit the Gulmarg Kashmir region in November 1978. Based on data collected from a door-to-door survey, the existence of a new disease, epidemic non-A, non-B hepatitis, caused by a hitherto unknown hepatitis virus, was announced. This news was received by the world community with hype and skepticism. In the early 1980s, the world watched in awe as an extreme example of human self-experimentation led to the identification of VLP. In 1990, a cDNA clone from the virus responsible for epidemic non-A, non-B hepatitis was isolated. Over the years, we traversed three eras of ambiguity, hope, and hype of hepatitis E research and conducted several seminal studies to understand the biology of HEV and manifestations of hepatitis E. Many milestones have been reached on the long and winding road of hepatitis E research to understand the structure, biology, and diversity of the agent, changing the behavior of the pathogen in developed countries, and the discovery of a highly effective vaccine.

Characterization of genotype IV hepatitis E virus-like particles expressed in E.coli

HEV (Hepatitis E virus) is an infectious disease transmitted between humans and animals, which poses a severe threat to the biological safety and property throughout the world. The disease is especially severe in patients with potential liver cirrhosis and women during pregnancy. There is no specific and thorough HEV treatment at present. The development of hepatitis E virus vaccine is vital to the prevention of viral hepatitis worldwide. Since HEV cannot grow adequately in vitro, vaccine developed by devitalized virus particles does not work. Exploration of HEV-like structures is essential for the development of functional vaccines against HEV infection. ORF2 encodes the structural proteins of HEV, some of which can automatically assemble into virus-like particles (VLP) in this experiment, the recombinant capsid protein p27 was expressed in E. coli and the VLP formed by p27 was used to immunize mice. The results showed that the VLP formed by recombinant P27 had similar particle size to that of HEV; the immune dose produced by p27 was positively correlated with the immune effect. Compared with other genetic engineering subunit vaccines, P27 protein has a better application prospect.

Severe hepatitis E infection in pregnancy: a case report

Hepatitis E virus causes self limiting hepatitis most of the times but, during pregnancy it can lead to severe hepatitis along with various complications thereby increasing the mortality.

Case presentation

A 27-year-old woman gravida two, para one at 38 weeks and 6 days of gestation presented with multiple episodes of nonbilious vomiting, severe dehydration, and later developed right upper quadrant abdominal pain. The patient had a positive serological test for the hepatitis E virus, and liver enzymes were severely elevated. Under supportive treatment she delivered a healthy baby, and her liver enzymes returned to normal levels after 2 weeks of delivery.

Clinical discussion

Although the hepatitis E virus usually causes self-limiting hepatitis, it can quickly progress to severe hepatitis, liver failure, and even death during pregnancy. Immunological change with a Th2 biased response and increased hormonal levels during pregnancy could possibly facilitate the development of severe liver damage. No particular drug has been approved for the treatment of hepatitis E viral infection in pregnant women, and the commonly used drugs are contraindicated due to the risk of teratogenicity. Supportive therapy and intensive monitoring are the core management techniques for hepatitis E virus infection in pregnant women.

Conclusion

Due to the high mortality risk, pregnant women should try to avoid possible exposure to the hepatitis E virus, but once infected, symptomatic therapy is the mainstay.

Molecular docking and dynamic simulation analysis of Hepatitis E virus protease in complexing with the E64 inhibitor

The unavailability of a suitable treatment for human Hepatitis E virus (HEV) infection necessitate the development of anti HEV drugs. The HEV papain-like cysteine proteases (HEV PCP) is a crucial target to prevent viral replication and progression. E64 is a known HEV PCP inhibitor; however, its molecular mechanism of inhibition is not yet known. Since the crystal structure of HEV PCP is not available, the primary focuses of the present study was to refine the predicted HEV PCP structural model by molecular dynamics (MD) simulation. Further, we performed a 200 ns MD simulation to understand the structural complexity of HEV PCP and the effect of E64 binding with HEV PCP. The E64 binding with active site residues Gln48, Thr51, Gln55, Cys52, Ser81, Gln 98, Cys 132, Arg158, His159, Asn 160 and Ala96 leads to reduced fluctuations in the residue at N-terminal (18-41) that include the CHC motif (26-28). However, most of the other non interacting residues, including the inter-domain linker region (46-87), showed increased fluctuations in the HEV PCP-E64 complex. The residue Asp21 and Ala96 are involved in the formation of interdomain interactions in the HEV PCP apo enzyme. While in the PCP-E64 complex, E64 binds to Ala96 and creates a steric hindrance to prevent interdomain interactions. Thus, the E64 binding reduces interdomain interactions and restrict domain movements in the HEV PCP-E64 complex. This information will be important for the chemically designing more effective derivatives of E64 developing HEV PCP specific inhibitors.Communicated by Ramaswamy H. Sarma.

Hepatitis Virus and Hepatocellular Carcinoma: Recent Advances

Hepatocellular carcinoma (HCC) remains a global health challenge, causing 600,000 deaths each year. Infectious factors, including hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV), have long been considered the major risk factors for the development and progression of HCC. These pathogens induce hepatocyte transformation through a variety of mechanisms, including insertional mutations caused by viral gene integration, epigenetic changes, and the induction of long-term immune dysfunction. The discovery of these mechanisms, while advancing our understanding of the disease, also provides targets for new diagnostic and therapeutic approaches. In addition, the discovery and research of chronic HEV infection over the past decade indicate that this common hepatitis virus also seems to have the potential to induce HCC. In this review, we provide an overview of recent studies on the link between hepatitis virus and HCC, as well as new diagnostic and therapeutic approaches to HCC based on these findings. Finally, we also discuss the potential relationship between HEV and HCC. In conclusion, these associations will further optimize the diagnosis and treatment of infection-associated HCC and call for better management policies.

Detection of Nonenveloped Hepatitis E Virus in Plasma of Infected Blood Donors

BACKGROUND

Transfusion-transmitted hepatitis E virus (HEV) infections have raised many concerns regarding the safety of blood products. To date, enveloped HEV particles have been described in circulating blood, whereas nonenveloped HEV virions have only been found in feces; however, no exhaustive studies have been performed to fully characterize HEV particles in blood.

METHODS

Using isopycnic ultracentrifugation, we determined the types of HEV particles in plasma of HEV-infected blood donors.

RESULTS

Nonenveloped HEV was detected in 8 of 23 plasma samples, whereas enveloped HEV was found in all of them. No association was observed between the presence of nonenveloped HEV and viral load, gender, or age at infection. However, samples with HEV-positive serology and/or increased levels of liver injury markers contained a higher proportion of nonenveloped HEV than samples with HEV-negative serology and normal levels of liver enzymes. These results were further confirmed by analyzing paired donation and follow-up samples of 10 HEV-infected donors who were HEV seronegative at donation but had anti-HEV antibodies and/or increased levels of liver enzymes at follow up.

CONCLUSIONS

The HEV-contaminated blood products may contain nonenveloped HEV, which may pose an additional risk to blood safety by behaving differently to pathogen inactivation treatments or increasing infectivity.

Chronic hepatitis E: Advancing research and patient care

The hepatitis E virus (HEV) was initially thought to exclusively cause acute hepatitis. However, the first diagnosis of chronic hepatitis E in transplant recipients in 2008 profoundly changed our understanding of this pathogen. We have now begun to understand that specific HEV genotypes can cause chronic infection in certain immunocompromised populations. Over the past decade, dedicated clinical and experimental research has substantiated knowledge on the epidemiology, transmission routes, pathophysiological mechanisms, diagnosis, clinical features and treatment of chronic HEV infection. Nevertheless, many gaps and major challenges remain, particularly regarding the translation of knowledge into disease prevention and improvement of clinical outcomes. This article aims to highlight the latest developments in the understanding and management of chronic hepatitis E. More importantly, we attempt to identify major knowledge gaps and discuss strategies for further advancing both research and patient care.

Development of 68Ga-Labeled Hepatitis E Virus Nanoparticles for Targeted Drug Delivery and Diagnostics with PET

Targeted delivery of diagnostics and therapeutics offers essential advantages over nontargeted systemic delivery. These include the reduction of toxicity, the ability to reach sites beyond biological barriers, and the delivery of higher cargo concentrations to diseased sites. Virus-like particles (VLPs) can efficiently be used for targeted delivery purposes. VLPs are derived from the coat proteins of viral capsids. They are self-assembled, biodegradable, and homogeneously distributed. In this study, hepatitis E virus (HEV) VLP derivatives, hepatitis E virus nanoparticles (HEVNPs), were radiolabeled with gallium-68, and consequently, the biodistribution of the labeled [⁶⁸Ga]Ga-DOTA-HEVNPs was studied in mice. The results indicated that [⁶⁸Ga]Ga-DOTA-HEVNPs can be considered as promising theranostic nanocarriers, especially for hepatocyte-targeting therapies.

Viral Hepatitis, Cholesterol Metabolism, and Cholesterol-Lowering Natural Compounds

Hepatitis is defined as inflammation of the liver; it can be acute or chronic. In chronic cases, the prolonged inflammation gradually damages the liver, resulting in liver fibrosis, cirrhosis, and sometimes liver failure or cancer. Hepatitis is often caused by viral infections. The most common causes of viral hepatitis are the five hepatitis viruses—hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), and hepatitis E virus (HEV). While HAV and HEV rarely (or do not) cause chronic hepatitis, a considerable proportion of acute hepatitis cases caused by HBV (sometimes co-infected with HDV) and HCV infections become chronic. Thus, many medical researchers have focused on the treatment of HBV and HCV. It has been documented that host lipid metabolism, particularly cholesterol metabolism, is required for the hepatitis viral infection and life cycle. Thus, manipulating host cholesterol metabolism-related genes and proteins is a strategy used in fighting the viral infections. Efforts have been made to evaluate the efficacy of cholesterol-lowering drugs, particularly 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, in the treatment of hepatitis viral infections; promising results have been obtained. This review provides information on the relationships between hepatitis viruses and host cholesterol metabolism/homeostasis, as well as the discovery/development of cholesterol-lowering natural phytochemicals that could potentially be applied in the treatment of viral hepatitis.

First Report of the HEV Seroprevalence and the Risk Factor Assessment in the West Bank, Palestine, during the Period of 2015-2017

Hepatitis E virus is emerging viral hepatitis with hyperendemicity in many countries. Data on the burden of disease is not available in Palestine. This study aims to determine the seroprevalence and the risk factors of the HEV among the general population of the West Bank, Palestine. In this cross-sectional study, a total of 432 sera samples from 40 localities in the eleven districts of the West Bank and Jerusalem, Palestine, during the period of March 2015 to March 2017, were tested for HEV-IgG. A structured questionnaire was used to collect data of the participants' demographics and disease risk factors. The overall seroprevalence was 3.7%. Level of education was significantly inversely associated with HEV seropositivity (P=0.04). Purely spatial analysis did not detect any significant cluster related to the distribution of HEV-IgG cases; however, living in the southern West Bank is shown to be significantly associated with HEV. Age was also associated with HEV seropositivity. The young (<19 years) and adults (>40 years) had the highest prevalence, compared to those between 20 to 39 years old (P=0.12). Furthermore, males and those in contact with animals were associated with HEV seropositivity (P=0.1 and 0.3, respectively). In conclusion, the seroprevalence of HEV IgG in the West Bank, Palestine is low. Several well-investigated risk factors cannot be supported by our results due to the small number of the positive HEV-IgG samples. Finally, this study is useful for providing a first look into the seroepidemiology of HEV in Palestine.

Transfusion-transmitted hepatitis E: What we know so far?

Hepatitis E virus (HEV) is a major cause of viral hepatitis globally. There is growing concern about transfusion-transmitted HEV (TT-HEV) as an emerging global health problem. HEV can potentially result in chronic infection in immunocompromised patients, leading to a higher risk of liver cirrhosis and even death. Between 0.0013% and 0.281% of asymptomatic blood donors around the world have HEV viremia, and 0.27% to 60.5% have anti-HEV immunoglobulin G. HEV is infectious even at very low blood concentrations of the virus. Immunosuppressed patients who develop persistent hepatitis E infection should have their immunosuppressant regimen reduced; ribavirin may be considered as treatment. Pegylated interferon can be considered in those who are refractory or intolerant to ribavirin. Sofosbuvir, a nucleotide analog, showed modest antiviral activity in some clinical studies but sustained viral response was not achieved. Therefore, rescue treatment remains an unmet need. The need for HEV screening of all blood donations remains controversial. Universal screening has been adopted in some countries after consideration of risk and resource availability. Various pathogen reduction methods have also been proposed to reduce the risk of TT-HEV. Future studies are needed to define the incidence of transmission through transfusion, their clinical features, outcomes and prognosis.

Risk of transfusion-transmitted hepatitis E virus infection from pool-tested platelets and plasma

BACKGROUND AND AIMS

Immunocompromised patients are at risk of chronic hepatitis E which can be acquired by blood transfusions. Currently, screening of blood donors (BDs) for HEV RNA with a limit of detection (LOD) of 2,000 IU/ml is required in Germany. However, this may result in up to 440,000 IU of HEV RNA in blood products depending on their plasma volume. We studied the residual risk of transfusion-transmitted (tt) HEV infection when an LOD of 2,000 IU/ml is applied.

METHODS

Highly sensitive individual donor testing for HEV RNA on the Grifols Procleix Panther system (LOD 7.89 IU/ml) was performed. HEV loads were quantified by real-time PCR.

RESULTS

Of 16,236 donors, 31 (0.19%) were HEV RNA positive. Three BDs had viral loads between 710 and 2,000 IU/ml, which pose a significant risk of tt hepatitis E with any type of blood product. Eight BDs had viral loads of >32 to 710 IU/ml, which pose a risk of tt hepatitis E with platelet or plasma transfusions because of their higher plasma volume compared to red blood cell concentrates. Eight of these 11 potentially infectious BDs were seronegative for HEV, indicating a recent infection. Only 8 of 31 donors had viral loads >2,000 IU/ml that would also have been detected by the required screening procedure and 12 had very low HEV loads (<32 IU/ml).

CONCLUSIONS

Screening of BDs with an LOD of 2,000 IU/ml reduced the risk of tt HEV infection by about 73% for red blood cell concentrates but by just 42% for platelet and fresh frozen plasma transfusions. Single donor screening (LOD <32 IU/ml) should lead to an almost 100% risk reduction.

LAY SUMMARY

Immunocompromised patients, such as solid organ or hematopoietic stem cell recipients, are at risk of chronic hepatitis E, which can be acquired via blood transfusions. The risk of transfusion-transmitted hepatitis E in these patients may not be sufficiently controlled by (mini-)pool hepatitis E virus RNA screening of blood donors. Single donor screening should be considered to improve the safety of blood products.

[Viral hepatitis A to E: prevalence, pathogen characteristics, and pathogenesis]

Bei der viralen Hepatitis handelt es sich um eine akute oder chronische Entzündung der Leber, die durch verschiedene Viren verursacht wird. Weltweit leiden derzeit ca. 325 Mio. Menschen an der chronischen Form. Jährlich versterben insgesamt ca. 1,6 Mio. an den Folgen einer viralen Hepatitis. Die Hepatitisviren werden in 5 Erregergruppen unterteilt, die mit den Buchstaben A bis E bezeichnet werden (HAV–HEV). Diese unterscheiden sich in Phylogenie, Übertragung, Epidemiologie, Wirtsspezifität, Lebenszyklus, Struktur und in speziellen Aspekten der Pathogenese.

Das strikt humanpathogene HAV, Teil der Familie Picornaviridae, induziert meist nur akute Hepatitiden und ist primär in Entwicklungsländern verbreitet. Das den Hepeviridae zugeordnete HEV beschreibt eine ähnliche Epidemiologie, ist jedoch durch sein zoonotisches Potenzial auch in Industrienationen weitverbreitet und kann zusätzlich eine chronische Erkrankung induzieren. Eine Chronifizierung tritt ebenso bei dem weltweit verbreiteten HBV (Hepadnaviridae) auf, dessen Satellitenvirus HDV (Kolmioviridae) das vorhandene kanzerogene Potenzial noch einmal erhöht. Das ebenfalls weltweit verbreitete HCV (Flaviviridae) birgt ein äußerst hohes Risiko der Chronifizierung und somit ebenfalls ein stark erhöhtes, kanzerogenes Potenzial.

Die Erreger der viralen Hepatitis unterscheiden sich in ihren Eigenschaften und Lebenszyklen. Eine differenzierte Betrachtung im Hinblick auf Epidemiologie, Nachweismethoden und Prävention ist daher angezeigt. Obwohl robuste Therapien, und im Falle einzelner Erreger auch Vakzine, vorhanden sind, muss die Forschung insbesondere in Hinblick auf die armutsassoziierten Erreger erheblich vorangetrieben werden.

Cell Division Control Protein 42 Interacts With Hepatitis E Virus Capsid Protein and Participates in Hepatitis E Virus Infection

Hepatitis E Virus (HEV) causes viral hepatitis in humans worldwide, while a subset of HEV species, avian HEV, causes hepatitis-splenomegaly syndrome in chickens. To date, there are few reports on the host proteins interacting with HEV and being involved in viral infection. Previous pull-down assay combining mass spectrometry indicated that cell division control protein 42 (CDC42), a member belonging to the Rho GTPase family, was pulled down by avian HEV capsid protein. We confirmed the direct interaction between CDC42 and avian and mammalian HEV capsid proteins. The interaction can increase the amount of active guanosine triphosphate binding CDC42 state (GTP-CDC42). Subsequently, we determined that the expression and activity of CDC42 were positively correlated with HEV infection in the host cells. Using the different inhibitors of CDC42 downstream signaling pathways, we found that CDC42-MRCK (a CDC42-binding kinase)-non-myosin IIA (NMIIA) pathway is involved in naked avian and mammalian HEV infection, CDC42-associated p21-activated kinase 1 (PAK1)-NMIIA/Cofilin pathway is involved in quasi-enveloped mammalian HEV infection and CDC42-neural Wiskott-Aldrich syndrome protein-actin-polymerizing protein Arp2/3 pathway (CDC42-(N-)WASP-Arp2/3) pathway participates in naked and quasi-enveloped mammalian HEV infection. Collectively, these results demonstrated for the first time that HEV capsid protein can directly bind to CDC42, and non- and quasi-enveloped HEV use different CDC42 downstream signaling pathways to participate in viral infection. The study provided some new insights to understand the life cycle of HEV in host cells and a new target of drug design for combating HEV infection.

Assessment of Knowledge, Attitude, and Practice among Saudi Residents Regarding Hepatitis E Virus

Global data, including those from Saudi Arabia, that examined public knowledge, attitudes, and practices (KAP) toward hepatitis E virus (HEV) are limited. This study examined KAP levels of the general population in Saudi Arabia toward HEV. A cross-sectional study was conducted among 768 participants. An Arabic electronic questionnaire that contained demographic data and had 35 questions was used to measure KAP of the participants concerning HEV. Collected data were analyzed at a significance level of 0.05. A total of 768 individuals participated in the study, of whom 16.3% (N = 125) were males and 83.7% (N = 643) were females. Study subjects were 18 years and above. Most of the participants were Saudi citizens (95.6%; N = 734), and from Western Saudi Arabia (76.4%; N = 587). Thirty-four percent (N = 261) of the participants had not heard of HEV, and 48% were aware that yellowish skin or eyes are the most important sign of hepatitis. The level of participants' knowledge about HEV was low (39.5%). However, positive attitudes and practices were apparent and tended to aim at how to avoid becoming infected with HEV. In conclusion, the level of HEV-related knowledge among the participants was low, and their practices and attitudes were aimed at avoiding HEV infection. Awareness campaigns are required to increase the public's HEV-related knowledge.

A quadruple recombination event discovered in hepatitis E virus

Hepatitis E virus (HEV) can infect humans, pigs, and many other animals, but recombination in HEV has rarely been reported. In the present study, phylogenetic and recombination analysis was performed on 557 complete HEV genome sequences from the GenBank database. A potentially significant quadruple recombination event was identified by recombination detection analysis. The recombinant progeny virus, HEV_32_Manchester_301214, was produced by inter-genotype recombination between the major parent HEPAC-44 and the minor parent HE-JA15-1335. HEV_32_Manchester_301214 and HEPAC-44 belong to genotype 3, while HE-JA15-1335 belongs to genotype 1, and these three strains were all isolated from humans. Three breakpoints of the four recombination events occurred in the ORF2 region, while another occurred in the ORF1 region. This quadruple recombination event was confirmed by phylogenetic analysis. The genotype, host, and recombination regions of the three strains were analyzed, and the analysis results provide valuable information for future research on HEV diversity.

Interplay between Hepatitis E Virus and Host Cell Pattern Recognition Receptors

Hepatitis E virus (HEV) usually causes self-limiting acute hepatitis, but the disease can become chronic in immunocompromised individuals. HEV infection in pregnant women is reported to cause up to 30% mortality, especially in the third trimester. Additionally, extrahepatic manifestations like neuronal and renal diseases and pancreatitis are also reported during the course of HEV infection. The mechanism of HEV pathogenesis remains poorly understood. Innate immunity is the first line of defense triggered within minutes to hours after the first pathogenic insult. Growing evidence based on reverse genetics systems, in vitro cell culture models, and representative studies in animal models including non-human primates, has implicated the role of the host’s innate immune response during HEV infection. HEV persists in presence of interferons (IFNs) plausibly by evading cellular antiviral defense. This review summarizes our current understanding of recognizing HEV-associated molecular patterns by host cell Pattern Recognition Receptors (PRRs) in eliciting innate immune response during HEV infection as well as mechanisms of virus-mediated immune evasion.

A Putative Novel Hepatitis E Virus Genotype 3 Subtype Identified in Rabbit, Germany 2016

Hepatitis E is an emerging viral disease that is the leading cause of viral hepatitis in the world. The vast majority of hepatitis E cases in developed countries are caused by zoonotic genotypes 3 and 4 of hepatitis E virus (HEV) for which pig and wild boar and to lesser extent rabbits are the main reservoir. According to recent reports rabbits are a source of human HEV infection and highlight the risk of zoonotic foodborne transmission. Here we report the molecular analysis of a novel HEV strain identified in a rabbit during a countrywide surveillance of rabbits and hares in Germany, 2016. The analysis of the complete genome reveals characteristics of a putative novel recombinant subtype of the species Orthohepevirus A within the clade of genotype 3 but not closely related to any known subtypes. Importantly, the genome of this strain possesses a nucleotide exchange in the overlapping region of open reading frames ORF2/ORF3 interfering with a broadly applied diagnostic real-time RT-PCR. In conclusion, a new type of HEV strain was identified in a German rabbit with atypical and novel sequence characteristics.

The different replication between nonenveloped and quasi-enveloped hepatitis E virus

Hepatitis E virus (HEV) is the major pathogen of viral hepatitis. However, the understanding of the HEV life cycle is limited. In the present study, cells were separately infected with nonenveloped HEV (derived from feces or bile) or quasi-enveloped HEV (derived from the cell culture after serial passages, eHEV) and observed by confocal fluorescence microscopy to investigate the life cycle of HEV. HEV finished its binding and entry into host cells at first 6 h postinoculation (hpi). Cells inoculated with eHEV showed less infectivity than cells inoculated with nonenveloped HEV. Newly synthesized progeny virions were released into the supernatant of cell cultures from 48 hpi. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis results showed that the supernatant's progeny viruses were infectious even after five serial passages. These results show the significant difference between nonenveloped HEV and eHEV, which will provide novel insights into the HEV replication cycle. The efficient cell culture of HEV will promote the development of anti-HEV drugs and vaccines.

Hepatitis E virus infection and waste pickers: A case-control seroprevalence study

Whether waste pickers are a risk group for hepatitis E virus (HEV) infection is largely unknown. This study aimed to determine the association between HEV exposure and the occupation of waste pickers and the work characteristics of waste pickers. An age-and gender-matched case-control seroprevalence study of 86 waste pickers and 86 control subjects of the general population was performed. We determined anti-HEV IgG antibodies in sera of cases and controls using a commercially available enzyme-linked immunoassay. The McNemar's test was used to assess the association between HEV seropositivity and the occupation of waste picker. The association between HEV seropositivity and work characteristics of waste pickers was assessed by bivariate and logistic regression analyses. Anti-HEV IgG antibodies were detected in 14 (16.3%) of the 86 waste pickers and in 8 (9.3%) of the 86 control subjects (McNemar's pair test: odds ratio (OR) = 13.0; 95% confidence interval (CI): 0.73-230.77; p = .02). Bivariate analysis showed that HEV exposure was associated with an ill status (p = .01) and reflexes impairment (p = .009). Logistic regression analysis showed that HEV seropositivity was associated with increasing age (OR = 6.52; 95% CI: 1.95-21.78; p = .002) and raising pigs (OR = 12.01; 95% CI: 1.48-97.26; p = .02). This is the first age- and gender-matched case-control study on the association between HEV infection and the occupation of waste picker. Waste pickers represent a risk group for HEV infection. Factors associated with HEV seropositivity found in this study may help in the design of optimal planning to avoid HEV infection.

Molecular Characterization and Seroprevalence of Hepatitis E Virus in Inflammatory Bowel Disease Patients and Solid Organ Transplant Recipients

Seroprevalence rates and molecular characterization of hepatitis E virus (HEV) prevalent in the Lithuanian human population has not yet been evaluated. Immunosuppressed individuals have been recognized as a risk group for chronic hepatitis due to HEV genotype 3 (HEV-3) infections. The objectives of the present study were to determine prevalence rates of anti-HEV antibodies among inflammatory bowel disease (IBD) patients and solid organ transplant (SOT) recipients, to isolate and characterize HEV strain present in the Lithuanian human population, and to investigate its capacity to infect non-human primate (MARC-145 and Vero), swine (PK-15) and murine (Neuro-2a) cells in vitro. In the present study, the significant difference of anti-HEV IgG prevalence between healthy (3.0% (95% CI 0–6.3)) and immunosuppressed individuals (12.0% [95% CI 8.1–15.9]) was described. Moreover, our findings showed that anti-HEV IgG seropositivity can be significantly predicted by increasing age (OR = 1.032, p < 0.01), diagnosis of IBD (OR = 4.541, p < 0.01) and reception of SOT (OR = 4.042, <0.05). Locally isolated HEV strain clustered within genotype 3i subtype of genotype 3 and was capable of infecting MARC-145 cells. This study demonstrates higher HEV seroprevalence in the risk group compared to healthy control individuals without confidence interval overlap. The high level of genetic homology between human and animal strains in Lithuania and the capacity of locally isolated strains to infect cells of non-human origin suggests its potential for zoonotic transmission.

Advances in Hepatitis E Virus Biology and Pathogenesis

Hepatitis E virus (HEV) is one of the causative agents for liver inflammation across the world. HEV is a positive-sense single-stranded RNA virus. Human HEV strains mainly belong to four major genotypes in the genus Orthohepevirus A, family Hepeviridae. Among the four genotypes, genotype 1 and 2 are obligate human pathogens, and genotype 3 and 4 cause zoonotic infections. HEV infection with genotype 1 and 2 mainly presents as acute and self-limiting hepatitis in young adults. However, HEV infection of pregnant women with genotype 1 strains can be exacerbated to fulminant hepatitis, resulting in a high rate of case fatality. As pregnant women maintain the balance of maternal-fetal tolerance and effective immunity against invading pathogens, HEV infection with genotype 1 might dysregulate the balance and cause the adverse outcome. Furthermore, HEV infection with genotype 3 can be chronic in immunocompromised patients, with rapid progression, which has been a challenge since it was reported years ago. The virus has a complex interaction with the host cells in downregulating antiviral factors and recruiting elements to generate a conducive environment of replication. The virus-cell interactions at an early stage might determine the consequence of the infection. In this review, advances in HEV virology, viral life cycle, viral interference with the immune response, and the pathogenesis in pregnant women are discussed, and perspectives on these aspects are presented.

Intestinal Viral Loads and Inactivation Kinetics of Livestock Viruses Relevant for Natural Casing Production: a Systematic Review and Meta-Analysis

Animal intestines are the source of edible sausage casings, which are traded worldwide and may come from areas where notifiable infectious animal diseases are prevalent. To estimate the risks of virus contamination, knowledge about the quantity of virus and decimal reduction values of the standard preservation method by salting is of great importance. A literature search, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, was performed in search engine CAB Abstracts to determine the viral load of 14 relevant animal viruses in natural casings or intestines. Only a very limited number of scientific publications per virus were found and viral loads in the intestines varied from high for ASFV (five publications), BVDV (3), CSFV (6), PPRV (3), RPV (2) and TGEV (3) to moderate for PEDV (2) and SVDV (3), low for HEV (2) and FMDV (5), very low for VESV (1) and negative for PrV (2) and VSV (1). PRRSV was found in intestines, however, viral titers were not published. Three viruses (BVDV, CSFV and PPRV) with high viral loads were selected to search for their inactivation kinetics. For casings, no inactivation data were found, however, thermal inactivation data of these viruses were available, but differed in quantity, quality and matrices. In conclusion, important data gaps still exist when it comes to the quantitative inactivation of viruses in sausage casings or livestock intestines.

Immunogenicity of gold nanoparticle-based truncated ORF2 vaccine in mice against Hepatitis E virus

This study presents nanoparticle-based vaccine development for Hepatitis E virus (HEV). Gold nanoparticles (GNP) of average size 12 nm were synthesized by citrate reduction method followed by functionalization with cysteamine hydrochloride for nano-conjugation. Immune response of nano-conjugates of GNP with 26 kDa protein (368-606 amino acids) and 54 kDa protein (112-606 amino acids) were evaluated. In vitro release kinetics of GNP-conjugated 54 kDa (GNP54) and 26 kDa (GNP26) proteins showed slower rate of release of 54 kDa protein as compared to 26 kDa protein. Humoral immune response of mice immunized intramuscularly with GNP54, GNP26 and GNP alone, exhibited HEV-specific IgG titer of 7.9 ± 2.9, 5.686 ± 4.098 and 0.698 ± 0.089, respectively, after 14 days of booster immunization. In addition to this, HEV-specific cell-mediated immune response was demonstrated by splenocyte proliferation assay. Analysis of results using one-way ANOVA, showed statistically significant (p value < 0.05) increase in splenocyte proliferation for GNP54- and GNP26-immunized mice in comparison to GNP alone immunized mice. Stimulation index of HEV ORF2 proteins in GNP54/GNP26-immunized mice were comparable to Concanavalin A-treated positive control. These results indicate GNP-based vaccine as a promising candidate for efficiently mediating both humoral and cell-mediated immune response against HEV.

Towards the Improved Accuracy of Hepatitis E Diagnosis in Vulnerable and Target Groups: A Global Perspective on the Current State of Knowledge and the Implications for Practice

The hepatitis E virus (HEV) is a positive single-stranded, icosahedral, quasi-enveloped RNA virus in the genus Orthohepevirus of the family Hepeviridae. Orthohepevirus A is the most numerous species of the genus Orthohepevirus and consists of eight different HEV genotypes that can cause infection in humans. HEV is a pathogen transmitted via the fecal-oral route, most commonly by consuming fecally contaminated water. A particular danger is the HEV-1 genotype, which poses a very high risk of vertical transmission from the mother to the fetus. Several outbreaks caused by this genotype have been reported, resulting in many premature births, abortions, and also neonatal and maternal deaths. Genotype 3 is more prevalent in Europe; however, due to the openness of the market, i.e., trade-in animals which represent a natural reservoir of HEV (such as pigs), there is a possibility of spreading HEV infections outside endemic areas. This problem is indeed global and requires increased hygiene measures in endemic areas, which entails special care for pregnant women in both endemic and non-endemic regions. As already highlighted, pregnant women could have significant health consequences due to the untimely diagnosis of HEV infection; hence, this is a population that should be targeted with a specific combination of testing approaches to ensure optimal specificity and sensitivity. Until we advance from predominantly supportive treatment in pregnancy and appraise the safety and efficacy of a HEV vaccine in this population, such screening approaches represent the mainstay of our public health endeavors.

Hepatitis E should be a global public health priority: recommendations for improving surveillance and prevention

INTRODUCTION

Hepatitis E virus (HEV) is an important cause of enterically transmitted viral hepatitis and a significant contributor to maternal mortality in endemic regions around the world, yet the global response has been limited. HEV is a disease of poverty, and the populations experiencing the greatest burden of HEV-associated illness are not benefitting from existing interventions, including WASH strategies and immunization.

AREAS COVERED

Though a vaccine exists (HEV 239, Hecolin®, Xiamen Innovax Biotech, China), it is only licensed and available in the private market in China and has yet to be prequalified by the WHO for use in endemic settings and outbreaks. This review of the current state of HEV disease and subsequent recommendations for a coordinated public health response are intended to guide the global health community towards breaking the current 'vicious cycle,' in which a lack of data prevents actions that would improve health outcomes.

EXPERT OPINION

Vaccine implementation in future outbreaks, targeted studies assessing vaccine effectiveness and immunogenicity in endemic regions and populations, improved understanding of the global burden, and improvements in diagnostic and epidemiologic tools are urgently needed. Strategies for implementing routine vaccination programs, improving water, sanitation, and hygiene in endemic regions.

Detection of Hepatitis E Virus in the Pig Livers and Retail Pork Samples Collected in Selected Cities in China

Hepatitis E virus (HEV) is a biological hazard that must be controlled and is a recognized etiological agent in viral hepatitis. This is a zoonotic virus and can be transmitted through the fecal-oral route. The pig is an important reservoir host of HEV, and is a source of contamination for the consumer after the consumption of raw or undercooked pork products. When detected, the most prevalent genotype of HEV in China is genotype 4 (denoted as HEV-4). To ensure the safety of this food of animal origin, we undertook a survey of HEV contamination in pig livers and pork samples available for sale, in retail outlets in selected cities in China. Viral RNA was purified from samples collected by lysing in Trizol followed by purification using trichloromethane and virus RNA extract kit. An additional step was applied to improve the recovery rate by adding RNase OUT when extracting virus RNA from pig livers, and the RNA productions were washed in 75% (v/v) ethanol to remove inhibitors. In total, 158 pig livers and 80 pork samples were procured and analyzed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). After purification of total RNA from all samples taken and analyzed by RT-qPCR, a single pig liver was positive by this method for HEV. The positive rate was calculated as 0.63%. In this study, a single positive sample was detected. Considering the dietary habits of Chinese people, pork is a popular food that on occasion may be contaminated with HEV, thereby posing a threat to consumer health. Ongoing surveillance is required to assess the risk to human health arising from HEV-contaminated pork being offered for sale, at retail outlets, especially in the areas of China where pig production is practiced.

Reverse genetics approaches for hepatitis E virus and related viruses

The hepatitis E virus (HEV) is the causative agent of acute and chronic hepatitis in humans. Related viruses have been found in several animal species. Reverse genetics systems (RGSs), which enable the generation of infectious virus from cloned cDNA by transfection of cultured cells or intrahepatic injection into laboratory animals, have been developed for HEV genotypes 1, 3, 4, 5 and 7 as well as for avian HEV and rat HEV. However, low virus recovery rates and slow replication in cell cultures are observed for most of the HEV types. Nevertheless, the RGSs enabled the site-directed mutagenesis of single nucleotides, deletion of genome fragments, insertion of sequence tags and a marker gene as well as the generation of chimeric viruses.

Hepatitis E virus infection during pregnancy

BACKGROUND

Hepatitis E virus (HEV) generally causes self-limiting viral hepatitis. However, in pregnant women, HEV infection can be severe and has been associated with up to 30% mortality in the third trimester. Additionally, HEV infection in pregnancy is also associated with high rates of preterm labor and vertical transmission.

MAIN BODY

HEV is now recognized as a global health problem in both developing and industrialized countries. HEV can be transmitted via the fecal-oral route, zoonotic route, and blood transfusion route. An altered immune status, hormonal levels, and viral factors may be related to the severity of the disease. Currently, no established treatment is available for HEV in pregnant women. A Chinese vaccine has been demonstrated to be protective against HEV in the general population and seems to be safe in pregnancy; however, its safety and efficacy in a large population of pregnant women remain to be determined.

CONCLUSION

This review summarizes the current knowledge about HEV infection during pregnancy and focuses on the epidemiology, clinical manifestations, mechanisms underlying severe liver injury, and management and prevention of HEV infection during pregnancy. Considering that HEV infection during pregnancy may result in poor outcomes, screening for and monitoring HEV infection early in pregnancy should be taken into account. In addition, a better understanding of the pathogenesis will help to develop potential treatment strategies targeting HEV infection in pregnancy.

Seroepidemiology of hepatitis E virus infection in patients undergoing maintenance hemodialysis: Systematic review and meta-analysis

Patients undergoing regular hemodialysis (HD) are at an extreme risk of acquiring bloodstream infections compared to the general population. Hepatitis E virus (HEV) infection is an important emerging health issue in these patients. To date, numerous studies have investigated the seroprevalence of HEV among HD patients across the world; however, the data are conflicting. The present study aimed to measure the exposure rate of HD patients to HEV infection by estimating the overall seroprevalence of HEV in this high-risk group. A systematic literature search was carried out using five electronic databases from inception to January 10, 2020, with standard keywords. Pooled seroprevalence estimates with 95% confidence intervals (CIs) were calculated using a random intercept logistic regression model. The seroprevalence of HEV increased from 6.6% between the years of 1994 and 2000 to 11.13% from 2016 to 2020. Blood transfusion was associated with a nearly 2-fold increase in the rate of HEV seropositivity (OR = 1.99; 95% CI: 1.50-2.63, P < .0001, I² = 6.5%). HEV seroprevalence among patients with HD for more than 60 months was significantly higher than those with HD for less than 60 months (27.69%, 95% CI: 20.69%-35.99% vs 15.78%, 95%CI: 8.85%-26.57%, respectively) (P = .06). Our results indicated increased exposure of HD patients with HEV infection over the last decade. We concluded that blood transfusion and duration of HD are considerable risk factors for acquiring HEV infection among HD patients.

Seroprevalence of Dromedary Camel HEV in Domestic and Imported Camels from Saudi Arabia

Hepatitis E Virus (HEV) imposes a major health concern in areas with very poor sanitation in Africa and Asia. The pathogen is transmitted mainly through ingesting contaminated water or food, coming into contact with affected people, and blood transfusions. Very few reports including old reports are available on the prevalence of HEV in Saudi Arabia in humans and no reports exist on HEV prevalence in camels. Dromedary camel trade and farming are increasing in Saudi Arabia with importation occurring unidirectionally from Africa to Saudi Arabia. DcHEV transmission to humans has been reported in one case from the United Arab Emeritus (UAE). This instigated us to perform this investigation of the seroprevalence of HEV in imported and domestic camels in Saudi Arabia. Serum samples were collected from imported and domestic camels. DcHEV-Abs were detected in collected sera using ELISA. The prevalence of DcHEV in the collected samples was 23.1% with slightly lower prevalence in imported camels than domestic camels (22.4% vs. 25.4%, p value = 0.3). Gender was significantly associated with the prevalence of HEV in the collected camels (p value = 0.015) where males (31.6%) were more infected than females (13.4%). This study is the first study to investigate the prevalence of HEV in dromedary camels from Saudi Arabia. The high seroprevalence of DcHEV in dromedaries might indicate their role as a zoonotic reservoir for viral infection to humans. Future HEV seroprevalence studies in humans are needed to investigate the role of DcHEV in the Saudi human population.

Stability of hepatitis E virus at different pH values

Infection with the hepatitis E virus (HEV) can cause acute and chronic hepatitis in humans. The zoonotic HEV genotype 3 is mainly transmitted by consumption of raw and fermented meat products prepared from infected pigs or wild boars. Lowering of pH during fermentation is one of the microbiological hurdles considered to inhibit growth of certain pathogens. However, no data are currently available on pH stability of HEV. As a reliable and reproducible measurement of HEV infectivity in meat products is not established so far, the stability of the cell culture-adapted HEV genotype 3 strain 47832c was analyzed here in phosphate-buffered saline (PBS) at different pH values. Only a minimal decrease of infectivity (up to 0.6 log₁₀ focus forming units) was found after treatment at pH 2 to 9 for 3 h at room temperature. At pH 10, a decrease of about 3 log₁₀ was evident, whereas no remaining virus (>3.5 log₁₀ decrease) was detected at pH 1. The conditions usually achieved during curing of raw sausages were simulated using D/L-lactic acid added to PBS resulting in pH 4.5 to 6.5. After incubation at 4 °C for 7 days at these conditions, no significant differences as compared to a standard PBS solution at pH 7.7 were evident. At room temperature, a 0.8 log₁₀ decrease was found at pH 4.7 after 7 days incubation compared to pH 7.7, but less at the other pH values. In conclusion, only minimal inactivating effects were found at pH conditions commonly occurring during food processing. Therefore, remaining infectious virus might be present in fermented meat products if HEV-contaminated starting material was used. Additional effects of other factors like high salt concentrations and low a_w values should be investigated in future studies.

Heterogeneous Nuclear Ribonucleoproteins Participate in Hepatitis E Virus Replication

Coordinated assembly of viral and host factors is essential for the successful propagation of viruses as well as the generation of host antiviral response. Previous studies from our group, as well as from other groups, have identified host proteins interacting with various components of the hepatitis E virus (HEV). However, the functional relevance of host protein interactions in HEV replication context has been notably overlooked. The present study reports that heterogeneous nuclear ribonucleoproteins (hnRNPs), namely hnRNPK, hnRNPA2B1, hnRNPH, PCBP1 and PCBP2, interact with HEV RNA promoter and RNA-dependent RNA polymerase to regulate HEV replication. We found that hnRNPK and hnRNPA2B1 are the virus-supportive factors interacting with HEV RNA at promoter regions along with HEV polymerase protein, which are essential for HEV replication in the cells. Contrarily, hnRNPH, PCBP1 and PCBP2 are the antiviral factors that interact exclusively with HEV genomic promoter and inhibit HEV replication in Huh7 S10-3 cells. In vitro RNA-binding assays revealed that the antiviral hnRNP proteins hamper the binding of virus-supportive hnRNP proteins at HEV genomic promoter. In the binding reaction, the binding of HEV polymerase protein to the genomic promoter is slightly affected by the presence of antiviral hnRNPH. In an effort of visualizing the subcellular localization of hnRNP proteins in the HEV replication scenario in the Huh7 cells, we showed that hnRNPK, hnRNPA2B1, hnRNPH, PCBP1 and PCBP2 redistribute from nucleus to cytoplasm. In conclusion, our study highlights the importance of hnRNP proteins in HEV replication regulation.

Advancement of capture immunoassay for real-time monitoring of hepatitis E virus-infected monkey

Rapid increasing outbreak of Hepatitis E virus (HEV) shows an urgent need of HEV detection. Instead of time consuming and expensive RT-qPCR, an efficient and quick monitoring system is in utmost demand which can be comparable with the RT-qPCR in term of reliability and detection limit. An advanced platform for immunoassay has been constructed in this study by a nanozyme that constitutes anti-HEV IgG antibody-conjugated gold nanoparticles (Ab-AuNPs) as core and in situ silver deposition on the surface of Ab-AuNPs as outer shell. The virus has been entrapped on the nanocomposites while the silver-shell has decomposed back to the silver ions (Ag⁺) by adding a tetramethylbenzidine (TMBZ) and hydrogen peroxide (H₂O₂) which indirectly quantifies the target virus concentration. Counterpart to only applying nanozyme, by incorporation of the enhanced effect of Ag shell on the AuNP-based nanozyme, the advance deposition has been confirmed to prove the signal amplification mechanism in the proposed immunoassay. Most importantly, the sensor performances have examined on the HEV, collected from the HEV-infected monkey over a period of 45 days. It was successfully correlated with the standard RT-qPCR data, showing the applicability of this immunoassay as a real-time monitoring on the HEV infection. The in situ formation of AuNPs@Ag as nanozyme in this capture immunoassay leads to a promising advancement over the conventional methods and nanozyme-based immunoassay in real application which can be a good substitute of RT-qPCR in near future.

Hepatitis E-related adverse pregnancy outcomes and their prevention by hepatitis E vaccine in a rabbit model

Hepatitis E virus (HEV) can lead to high mortality during pregnancy. This study was to investigate the adverse pregnancy outcomes caused by different HEV genotypes and their prevention by HEV 239 vaccine in rabbits. Forty-two female rabbits were randomly and equally divided into 7 groups (A-G). HEV 239 vaccine and a placebo were administered to groups E (10 μg×2), F (5 μg×2) and G (1 mL of PBS×2) before copulation. After pregnancy, 1 mL of 1.5×106 copies/mL rabbit HEV3 was inoculated to groups A, E, F and G, swine HEV4/human HEV3 to groups B/C, and group D was a negative control. Anti-HEV antibody, HEV RNA, and alanine aminotransferase (ALT)/aspartate aminotransferase (AST) levels were monitored. Pregnant rabbits infected by HEV manifested HEV infection symptoms including fecal virus shedding, ALT/AST elevation, and histopathological changes, and adverse pregnancy outcomes. Immunized pregnant rabbits in groups E and F showed no HEV infection symptoms and adverse outcomes. The newborn rabbits delivered by pregnant rabbits with/without immunization showed without/with HEV infection symptoms. This study demonstrated that multiple genotypes of HEV infection can cause adverse outcomes and HEV 239 vaccine can prevent HEV-related adverse outcomes in pregnant rabbits.

Protein Interactions Network of Hepatitis E Virus RNA and Polymerase With Host Proteins

Host-pathogen interactions are crucial for the successful propagation of pathogens inside the host cell. Knowledge of interactions between host proteins and viral proteins or viral RNA may provide clues for developing novel antiviral strategies. Hepatitis E virus (HEV), a water-borne pathogen that causes acute hepatitis in humans, is responsible for epidemics in developing countries. HEV pathology and molecular biology have been poorly explored due to the lack of efficient culture systems. A contemporary approach, to better understand the viral infection cycle at the molecular level, is the use of system biology tools depicting virus-host interactions. To determine the host proteins which participate in the regulation of HEV replication, we indentified liver cell proteins interacting with HEV RNA at its putative promoter region and those interacting with HEV polymerase (RdRp) protein. We employed affinity chromatography followed by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF/MS) to identify the interacting host proteins. Protein-protein interaction networks (PPI) were plotted and analyzed using web-based tools. Topological analysis of the network revealed that the constructed network is potentially significant and relevant for viral replication. Gene ontology and pathway enrichment analysis revealed that HEV RNA promoter- and polymerase-interacting host proteins belong to different cellular pathways such as RNA splicing, RNA metabolism, protein processing in endoplasmic reticulum, unfolded protein response, innate immune pathways, secretory vesicle pathway, and glucose metabolism. We showed that hnRNPK and hnRNPA2B1 interact with both HEV putative promoters and HEV RdRp, which suggest that they may have crucial roles in HEV replication. We demonstrated in vitro binding of hnRNPK and hnRNPA2B1 proteins with the HEV targets in the study, assuring the authenticity of the interactions obtained through mass spectrometry. Thus, our study highlights the ability of viruses, such as HEV, to maneuver host systems to create favorable cellular environments for virus propagation. Studying the host-virus interactions can facilitate the identification of antiviral therapeutic strategies and novel targets.