scholarly journals Epitope–Paratope Interaction of a Neutralizing Human Anti-Hepatitis B Virus PreS1 Antibody That Recognizes the Receptor-Binding Motif

Vaccines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 754
Author(s):  
Jisu Hong ◽  
Youngjin Choi ◽  
Yoonjoo Choi ◽  
Jiwoo Lee ◽  
Hyo Jeong Hong
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Receptor Binding ◽  
Neutralizing Antibody ◽  
Hbv Infection ◽  
Binding Motif ◽  
Alanine Scanning Mutagenesis ◽  
B Virus ◽  
Complementarity Determining Regions

Hepatitis B virus (HBV) is a global health burden that causes acute and chronic hepatitis. To develop an HBV-neutralizing antibody that effectively prevents HBV infection, we previously generated a human anti-preS1 monoclonal antibody (1A8) that binds to genotypes A–D and validated its HBV-neutralizing activity in vitro. In the present study, we aimed to determine the fine epitope and paratope of 1A8 to understand the mechanism of HBV neutralization. We performed alanine-scanning mutagenesis on the preS1 (aa 19–34, genotype C) and the heavy (HCDR) and light (LCDR) chain complementarity-determining regions. The 1A8 recognized the three residues (Leu22, Gly23, and Phe25) within the highly conserved receptor-binding motif (NPLGFFP) of the preS1, while four CDR residues of 1A8 were critical in antigen binding. Structural analysis of the epitope–paratope interaction by molecular modeling revealed that Leu100 in the HCDR3, Ala50 in the HCDR2, and Tyr96 in the LCDR3 closely interacted with Leu22, Gly23, and Phe25 of the preS1. Additionally, we found that 1A8 also binds to the receptor-binding motif (NPLGFLP) of infrequently occurring HBV. The results suggest that 1A8 may broadly and effectively block HBV entry and thus have potential as a promising candidate for the prevention and treatment of HBV infection.

scholarly journals Primary Tupaia Javanica Hepatocyte Culture as an In Vitro Model for Human Hepatitis B Virus Infection

2022 ◽  
Vol 22 (3) ◽  
pp. 203-209
Author(s):  
Kemal Fariz Kalista ◽  
Maryati Surya ◽  
Silmi Mariya ◽  
Diah Iskandriati ◽  
Irsan Hasan ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
In Vitro Model ◽  
Hbv Dna ◽  
Hbv Infection ◽  
Primate Research ◽  
Qualitative And Quantitative ◽  
B Virus ◽  
Vitro Model

Background: Hepatitis B virus (HBV) infection is still one of the biggest health problems in the world, which could lead to chronic hepatitis, cirrhosis and hepatocellular carcinoma. Treatment for HBV infection has not yet achieved a functional cure. More studies are needed to investigate human HBV (HuHBV), but the scarcity of animal models for HuHBV infection became a barrier. Recently, many studies have shown that Tupaia are suitable for the study of HuHBV. The purpose of this study was to develop a primary tupaia hepatocyte (PTH) culture from T. javanica, a species of Tupaia found in Indonesia, and to prove that HuHBV can replicate in the PTH.Method: In vitro experimental study using PTH isolated from five wild adult T. javanica in Primate Research Center, IPB University. HuHBV was taken from humans with HBsAg and HBV-DNA (+). PTH cells then were infected with HuHBV after reaching 80% confluence. Observation on PTH cells was done everyday for 20 days. Qualitative and quantitative HBsAg were measured using a CMIA while HBV-DNA and cccDNA were measured by RT-PCR.Results: A cytopathic effect was seen on day post infection (DPI)-16. HBsAg and HBV-DNA were detected from DPI-2 until DPI-18, with HBV-DNA level peaked on DPI-12. cccDNA concentration was fluctuating from DPI-2 until DPI-20 with highest level on DPI-16.Conclusion: HuHBV could infect and replicate in PTH from T. javanica can be infected with HuHBV and HuHBV can replicate in the PTH from T. javanica.

Over IFI16 expression increased inflammation in Hepatitis B Virus-Associated Glomerulonephritis by Regulating Caspase-1 and IL-1 ß

2020 ◽  
Author(s):  
zhaoqing zeng ◽  
yuyang li ◽  
jinhong yu ◽  
jing liu ◽  
shijun chen ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Cell Line ◽  
Renal Damage ◽  
Hbv Infection ◽  
Inflammatory Factors ◽  
Inflammasome Activation ◽  
Caspase 1 ◽  
B Virus

Abstract Aims & background: IFI16 plays an important role in innate immunity against invasive microbial infection by sensing double-stranded DNA viruses due to caspase-1-dependent inflammasome activation and subsequent maturation and secretion of IL-1β. However, the role of IFI16 in regulating the immune response to viruses in vivo and in vitro, especially in sensing hepatitis B virus (HBV), has not been examined. We hypothesized that the expression of IFI16 increases corresponding to HBV-mediated inflammation in patients with hepatitis B virus associated glomerulonephritis (HBV-GN), a condition which activates inflammatory mechanisms and causes renal damage. To test this hypothesis, we therefore analyzed the expression of IFI16 and inflammatory factors in HBV-GN tissues and cell lines relative to the inflammatory response to HBV infection. Methods: A total 75 patients with chronic nephritis(CN) including 50 with HBV-GN and 25 with chronic glomerulonephritis (CCN) involved in this study. Each CN patient received renal biopsy, and immunohistochemistry(IHC) was used to detect the expression of IFI16 and inflammatory factors Caspase-1 and IL-1β in the biopsy specimens. Following IFI16 was transfected in HBV-infected and HBV-uninfected human glomerular mesangial (HGM) cell line and HEK-293T cell line, expression of Caspase-1 and IL-1β were detected by Western blot and qRT- PCR. Results: IFI16 expression in HBV-GN biopsies (80.0%) was significantly higher than in CGN (24.0%) and positively correlated with caspase-1 and IL-1𝛽 expression in HBV-GN. In vitro, over expression IFI16 increased caspase-1 and IL-1𝛽 expression in HBV -infected HGM and HEK-293T. Conclusions: The elevation of IFI16 during HBV infection or replication may contribute to renal damage due to inflammation, thus providing a putative therapeutic target and a new avenue for researching the pathogenesis of HBV-GN.

scholarly journals Identification and characterization of SEC24D as a susceptibility gene for hepatitis B virus infection

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Xianzhong Jiang ◽  
Bin Zhang ◽  
Junsheng Zhao ◽  
Yi Xu ◽  
Haijun Han ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Time Course ◽  
Expression Profiles ◽  
Association Studies ◽  
Susceptibility Gene ◽  
Hbv Infection ◽  
Genome Wide Association Studies ◽  
B Virus

Abstract Single nucleotide polymorphisms (SNPs) and genes associated with susceptibility to hepatitis B virus (HBV) infection that have been identified by genome-wide association studies explain only a limited portion of the known heritability, indicating more genetic variants remain to be discovered. In this study, we adopted a new research strategy to identify more susceptibility genes and variants for HBV infection. We first performed genetic association analysis of 300 sib-pairs and 3,087 case-control samples, which revealed that 36 SNPs located in 31 genes showed nominal associations with HBV infection in both samples. Of these genes, we selected SEC24D for further molecular analysis according to the following two main lines of evidence. First, a time course analysis of the expression profiles from HBV-infected primary human hepatocytes (PHH) demonstrated that SEC24D expression increased markedly as time passed after HBV infection (P = 4.0 × 10−4). Second, SNP rs76459466 in SEC24D was adversely associated with HBV risk (ORmeta = 0.82; Pmeta = 0.002), which again indicated that SEC24D represents a novel susceptibility gene for HBV infection. Moreover, SEC24D appeared to be protective against HBV infection in vitro. Consistently, we found that SEC24D expression was significantly enhanced in non-infected liver tissues (P = 0.002). We conclude that SEC24D is a novel candidate gene linked to susceptibility to HBV infection.

scholarly journals IFI16 induces inflammation in Hepatitis B Virus-Associated Glomerulonephritis by Regulating the Caspase-1 /IL-1ß pathway

2021 ◽  
Author(s):  
Li Liu ◽  
Xiuhua Zhao ◽  
Shuangshuang Xie ◽  
Cheng Li ◽  
Yue Guo ◽  
...  
Keyword(s):  
Immune Response ◽  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Cell Line ◽  
293T Cell ◽  
Hbv Infection ◽  
Caspase 1 ◽  
B Virus

Abstract Aims & backgroundIFI16 plays an important role in innate immunity against invasive microbial infection by sensing double-stranded DNA viruses due to caspase-1-dependent inflammasome activation and subsequent maturation and secretion of IL-1β. However, the role of IFI16 in regulating the immune response to viruses in Hepatitis B Virus-Associated Glomerulonephritis(HBV-GN), especially in sensing the hepatitis B virus (HBV), has not been determined. In this study,, we investigated the inflammatory role of IFI16 in HBV-GN.MethodsA total of 75 kidney tissues including 50 HBV-GN and 25 chronic glomerulonephritis (CCN) were collected to determine expression of IFI16, Caspase-1, and IL-1𝛽 by immunohistochemistry (IHC), and then the correlation between them was analyzed. In vitro, the overexpression or knockdown of IFI16 in regulating the immune response to HBV infection in the human glomerular mesangial (HGM) cell line and HEK-293T cell line. Quantitative Real-time PCR and western blotting were used to determine the expression of IFI16, Caspase-1 and IL-1β. The role effect of IFI16 in vivo was further investigated.ResultsIFI16 expression in HBV-GN biopsies (80.0%) was significantly higher than in CGN (24.0%) and was positively correlated with caspase-1 and IL-1𝛽 expression in HBV-GN. In vitro, over expression of IFI16 increased caspase-1 and IL-1𝛽 expression in HBV-infected HGM and HEK-293T cell lines, whereas knockdown of IFI16 mRNA by siRNA resulted in downregulation of the caspase-1 and IL-1𝛽 expression in both cell lines.ConclusionsThe elevation of IFI16 during HBV infection or replication may contribute to renal damage due to inflammation, thus providing a putative therapeutic target and a new avenue for studying the pathogenesis of HBV-GN.

scholarly journals RNA-Binding Motif Protein 24 (RBM24) Is Involved in Pregenomic RNA Packaging by Mediating Interaction between Hepatitis B Virus Polymerase and the Epsilon Element

2019 ◽  
Vol 93 (6) ◽  
Author(s):  
Yongxuan Yao ◽  
Bo Yang ◽  
Yingshan Chen ◽  
Hui Wang ◽  
Xue Hu ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Rna Binding ◽  
Binding Activity ◽  
Hbv Infection ◽  
Binding Motif ◽  
Independent Manner ◽  
Stem Loop ◽  
Hbv Replication ◽  
B Virus

ABSTRACTEncapsidation of pregenomic RNA (pgRNA) is a crucial step in hepatitis B virus (HBV) replication. Binding by viral polymerase (Pol) to the epsilon stem-loop (ε) on the 5′-terminal region (TR) of pgRNA is required for pgRNA packaging. However, the detailed mechanism is not well understood. RNA-binding motif protein 24 (RBM24) inhibits core translation by binding to the 5′-TR of pgRNA. Here, we demonstrate that RBM24 is also involved in pgRNA packaging. RBM24 directly binds to the lower bulge of ε via RNA recognition submotifs (RNPs). RBM24 also interacts with Pol in an RNA-independent manner. The alanine-rich domain (ARD) of RBM24 and the reverse transcriptase (RT) domain of Pol are essential for binding between RBM24 and Pol. In addition, overexpression of RBM24 increases Pol-ε interaction, whereas RBM24 knockdown decreases the interaction. RBM24 was able to rescue binding between ε and mutant Pol lacking ε-binding activity, further showing that RBM24 mediates the interaction between Pol and ε by forming a Pol-RBM24-ε complex. Finally, RBM24 significantly promotes the packaging efficiency of pgRNA. In conclusion, RBM24 mediates Pol-ε interaction and formation of a Pol-RBM24-ε complex, which inhibits translation of pgRNA and results in pgRNA packing into capsids/virions for reverse transcription and DNA synthesis.IMPORTANCEHepatitis B virus (HBV) is a ubiquitous human pathogen, and HBV infection is a major global health burden. Chronic HBV infection is associated with the development of liver diseases, including fulminant hepatitis, hepatic fibrosis, cirrhosis, and hepatocellular carcinoma. A currently approved vaccine can prevent HBV infection, and medications are able to reduce viral loads and prevent liver disease progression. However, current treatments rarely achieve a cure for chronic infection. Thus, it is important to gain insight into the mechanisms of HBV replication. In this study, we found that the host factor RBM24 is involved in pregenomic RNA (pgRNA) packaging and regulates HBV replication. These findings highlight a potential target for antiviral therapeutics of HBV infection.

Involvement of phosphatidylserine and non-phospholipid components of the hepatitis B virus envelope in human Annexin V binding and in HBV infection in vitro

1999 ◽  
Vol 31 (5) ◽  
pp. 783-790 ◽  
Author(s):  
Sandra De Meyer ◽  
Zuojiong Gong ◽  
Erik Depla ◽  
Geert Maertens ◽  
Sing Hiem Yap
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Annexin V ◽  
Hbv Infection ◽  
Virus Envelope ◽  
B Virus

scholarly journals AIM2 Mediates Inflammation-Associated Renal Damage in Hepatitis B Virus-Associated Glomerulonephritis by Regulating Caspase-1, IL-1β, and IL-18

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Junhui Zhen ◽  
Le Zhang ◽  
Jiachao Pan ◽  
Shumin Ma ◽  
Xiaojian Yu ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Renal Damage ◽  
Hbv Infection ◽  
Inflammatory Factors ◽  
Chronic Glomerulonephritis ◽  
Caspase 1 ◽  
Chronic Nephritis ◽  
B Virus

Background & Aims. AIM2 plays an important role in innate immunity, but its role in regulating the immune response to hepatitis B virus (HBV) is unknown. We hypothesized that AIM2 expression is positively correlated with HBV-mediated inflammation in patients with HBV-associated glomerulonephritis (HBV-GN), potentiating inflammation and leading to renal damage. We therefore analyzed the expression of AIM2 and inflammatory factors in HBV-GN tissues and cell lines relative to the inflammatory response to HBV infection and HBV status.Methods. Seventy-nine patients with chronic nephritis (CN) were included: 54 with HBV-GN and 24 with chronic glomerulonephritis (CGN). Expression of AIM2, caspase-1, and IL-1βwas detected by immunohistochemistry in renal biopsies from each patient. Following siRNA-mediated knockdown of AIM2 in HBV-infected and HBV-uninfected human glomerular mesangial (HGM) cells, expression of caspase-1, IL-1β, and IL-18 was detected by qRT-PCR and Western blot.Results. AIM2 expression in HBV-GN biopsies (81.4%) was significantly higher than in CGN (4.0%) and positively correlated with caspase-1 and IL-1βexpression in HBV-GN. In vitro, AIM2 knockdown reduced caspase-1, IL-1β, and IL-18 expression in HBV-infected and HBV-uninfected HGM cells.Conclusion. AIM2 elevation during HBV infection or replication may contribute to inflammatory damage, thus providing a putative therapeutic target for HBV-GN.

scholarly journals Analysis of Host Range Phenotypes of Primate Hepadnaviruses by In Vitro Infections of Hepatitis D Virus Pseudotypes

2004 ◽  
Vol 78 (10) ◽  
pp. 5233-5243 ◽  
Author(s):  
Azeneth Barrera ◽  
Bernadette Guerra ◽  
Helen Lee ◽  
Robert E. Lanford
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Host Range ◽  
Receptor Binding ◽  
Human Hepatocytes ◽  
Spider Monkey ◽  
Hepatitis D ◽  
Hepatitis D Virus ◽  
B Virus

ABSTRACT Hepatitis B virus (HBV) and woolly monkey hepatitis B virus (WMHBV) have natural host ranges that are limited to closely related species. The barrier for infection of primates seems to be at the adsorption and/or entry steps of the viral replication cycle, since a human hepatoma cell line is permissive for HBV and WMHBV replication following transfection of cloned DNA. We hypothesized that the HBV and WMHBV envelope proteins contain the principal viral determinants of host range. As previously shown by using the hepatitis D virus (HDV) system, recombinant HBV-HDV particles were infectious in chimpanzee as well as human hepatocytes. We extended the HDV system to include HDV particles pseudotyped with the WMHBV envelope. In agreement with the natural host ranges of HBV and WMHBV, in vitro infections demonstrated that HBV-HDV and WM-HDV particles preferentially infected human and spider monkey cells, respectively. Previous studies have implicated the pre-S1 region of the large (L) envelope protein in receptor binding and host range; therefore, recombinant HDV particles were pseudotyped with the hepadnaviral envelopes containing chimeric L proteins with the first 40 amino acids from the pre-S1 domain exchanged between HBV and WMHBV. Surprisingly, addition of the human amino terminus to the WMHBV L protein increased infectivity on spider monkey hepatocytes but did not increase infectivity for human hepatocytes. Based upon these data, we discuss the possibility that the L protein may be comprised of two domains that affect infectivity and that sequences downstream of residue 40 may influence host range and receptor binding or entry.

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