scholarly journals Properties of Subviral Particles of Hepatitis B Virus

2008 ◽  
Vol 82 (16) ◽  
pp. 7812-7817 ◽  
Author(s):  
Ning Chai ◽  
Ho Eun Chang ◽  
Emmanuelle Nicolas ◽  
Ziying Han ◽  
Michal Jarnik ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Hepatitis Delta Virus ◽  
Envelope Proteins ◽  
Infectious Particle ◽  
B Virus ◽  
Made In ◽  
Delta Virus ◽  
Bind Cell Surface ◽  
Subviral Particles

ABSTRACT In the sera of patients infected with hepatitis B virus (HBV), in addition to infectious particles, there is an excess (typically 1,000- to 100,000-fold) of empty subviral particles (SVP) composed solely of HBV envelope proteins in the form of relatively smaller spheres and filaments of variable length. Hepatitis delta virus (HDV) assembly also uses the envelope proteins of HBV to produce an infectious particle. Rate-zonal sedimentation was used to study the particles released from liver cell lines that produced SVP only, HDV plus SVP, and HBV plus SVP. The SVP made in the absence of HBV or HDV were further examined by electron microscopy. They bound efficiently to heparin columns, consistent with an ability to bind cell surface glycosaminoglycans. However, unlike soluble forms of HBV envelope protein that were potent inhibitors, the SVP did not inhibit the ability of HBV and HDV to infect primary human hepatocytes.

scholarly journals Role of N Glycosylation of Hepatitis B Virus Envelope Proteins in Morphogenesis and Infectivity of Hepatitis Delta Virus

2003 ◽  
Vol 77 (9) ◽  
pp. 5519-5523 ◽  
Author(s):  
Camille Sureau ◽  
Chantal Fournier-Wirth ◽  
Patrick Maurel
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Hepatitis Delta Virus ◽  
Envelope Proteins ◽  
Virus Envelope ◽  
Hepatitis Delta ◽  
B Virus ◽  
L Proteins ◽  
Delta Virus

ABSTRACT Hepatitis delta virus (HDV) particles are coated with the large (L), middle (M), and small (S) hepatitis B virus envelope proteins. In the present study, we constructed glycosylation-defective envelope protein mutants and evaluated their capacity to assist in the maturation of infectious HDV in vitro. We observed that the removal of N-linked carbohydrates on the S, M, and L proteins was tolerated for the assembly of subviral hepatitis B virus (HBV) particles but was partially inhibitory for the formation of HDV virions. However, when assayed on primary cultures of human hepatocytes, virions coated with S, M, and L proteins lacking N-linked glycans were infectious. Furthermore, in the absence of M, HDV particles coated with nonglycosylated S and L proteins retained infectivity. These results indicate that carbohydrates on the HBV envelope proteins are not essential for the in vitro infectivity of HDV.

scholarly journals Role of the Antigenic Loop of the Hepatitis B Virus Envelope Proteins in Infectivity of Hepatitis Delta Virus

2005 ◽  
Vol 79 (16) ◽  
pp. 10460-10466 ◽  
Author(s):  
Georges Abou Jaoudé ◽  
Camille Sureau
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Viral Entry ◽  
Hepatitis Delta Virus ◽  
Envelope Proteins ◽  
Single Amino Acid ◽  
Hepatitis Delta ◽  
B Virus ◽  
Virion Surface ◽  
Delta Virus

ABSTRACT The infectious particles of hepatitis B virus (HBV) and hepatitis delta virus (HDV) are coated with the large, middle, and small envelope proteins encoded by HBV. While it is clear that the N-terminal pre-S1 domain of the large protein, which is exposed at the virion surface, is implicated in binding to a cellular receptor at viral entry, the role in infectivity of the envelope protein antigenic loop, also exposed to the virion surface and accessible to neutralizing antibodies, remains to be established. In the present study, mutations were created in the antigenic loop of the three envelope proteins, and the resulting mutants were evaluated for their capacity to assist in the maturation and infectivity of HDV. We observed that short internal combined deletions and insertions, affecting residues 109 to 133 in the antigenic loop, were tolerated for secretion of both subviral HBV particles and HDV virions. However, when assayed for infectivity on primary cultures of human hepatocytes or on the recently described HepaRG cell line, virions carrying deletions between residues 118 and 129 were defective. Single amino acid substitutions in this region revealed that Gly-119, Pro-120, Cys-121, Arg-122, and Cys-124 were instrumental in viral entry. These results demonstrate that in addition to a receptor-binding site previously identified in the pre-S1 domain of the L protein, a determinant of infectivity resides in the antigenic loop of HBV envelope proteins.

scholarly journals Entry of Hepatitis Delta Virus Requires the Conserved Cysteine Residues of the Hepatitis B Virus Envelope Protein Antigenic Loop and Is Blocked by Inhibitors of Thiol-Disulfide Exchange

2007 ◽  
Vol 81 (23) ◽  
pp. 13057-13066 ◽  
Author(s):  
Georges Abou-Jaoudé ◽  
Camille Sureau
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Viral Entry ◽  
Hepatitis Delta Virus ◽  
Envelope Proteins ◽  
Single Amino Acid ◽  
Hepatitis Delta ◽  
Disulfide Exchange ◽  
B Virus ◽  
Delta Virus

ABSTRACT Hepatitis delta virus (HDV) particles are coated with the envelope proteins (large, middle, and small) of the hepatitis B virus (HBV). The large protein bears an infectivity determinant in its pre-S1 domain, whereas a second determinant has been proposed to map to the cysteine-rich antigenic loop (AGL) within the S domain of all three envelope proteins (G. Abou Jaoudé and C. Sureau, J. Virol. 79:10460-10466, 2006). In this study, the AGL cysteines were substituted by serine or alanine, and the mutants were evaluated for their function at viral entry using HDV particles and susceptible HepaRG cells. Mutations of cysteines 121 to 149 were tolerant of the production of HDV virions. The mutations altered the structure and antigenicity of the conserved “a” determinant of the AGL, as measured by conformation-sensitive antibodies, and they created a block to infectivity. Substitution of Cys-90 or Cys-221, located outside of the AGL, had no impact on the “a” determinant or viral entry. Furthermore, infectivity was maintained when the AGL CxxC motif at position 121 to 124 was modified by single-amino-acid deletion or insertion, suggesting that cysteines 121 and 124 are not catalyzers of thiol/disulfide exchange. However, membrane-impermeable inhibitors of thiol/disulfide isomerazation demonstrated a dose-dependent inhibition of infection in an in vitro assay when applied to the virus prior to inoculation or during the virus-cell interaction period. Overall, the results demonstrate the essential role of the AGL cysteines at viral entry, and they establish a correlation between the cysteine disulfide network, the conformation of the “a” determinant, and infectivity.

scholarly journals Analysis of Multiple Liver Explant Pieces Reveals that Levels of Hepatitis Delta Virus RNA Are Independent of Hepatitis B Virus Expression

2021 ◽  
Author(s):  
Kasthuri Prakash ◽  
Simon B. Larsson ◽  
Gustaf E. Rydell ◽  
Johan Ringlander ◽  
Catarina Skoglund ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Hepatitis Delta Virus ◽  
Hepatitis Delta ◽  
Virus Rna ◽  
B Virus ◽  
Virus Expression ◽  
Delta Virus

Occurrence of Hepatitis Delta Virus Infection in Hepatitis B Virus-Infected Patients with Different Serum Patterns of PreS Gene-Encoded Proteins

Digestion ◽  
1993 ◽  
Vol 54 (1) ◽  
pp. 9-14
Author(s):  
Nicola Napoli ◽  
Giorgio Fiore ◽  
Giacomo Fera ◽  
Angela Modugno ◽  
Gianluigi Giannelli ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Virus Infection ◽  
Hepatitis B ◽  
Hepatitis Delta Virus ◽  
Hepatitis Delta ◽  
Hepatitis Delta Virus Infection ◽  
B Virus ◽  
Encoded Proteins ◽  
Delta Virus

scholarly journals A Divergent Hepatitis D-Like Agent in Birds

Viruses ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 720 ◽  
Author(s):  
Michelle Wille ◽  
Hans Netter ◽  
Margaret Littlejohn ◽  
Lilly Yuen ◽  
Mang Shi ◽  
...  
Keyword(s):  
Amino Acid ◽  
Hepatitis B Virus ◽  
Sequence Analysis ◽  
Hepatitis B ◽  
Hepatitis Delta Virus ◽  
Amino Acid Similarity ◽  
Hepatitis D ◽  
Delta Antigen ◽  
B Virus ◽  
Delta Virus

Hepatitis delta virus (HDV) is currently only found in humans and is a satellite virus that depends on hepatitis B virus (HBV) envelope proteins for assembly, release, and entry. Using meta-transcriptomics, we identified the genome of a novel HDV-like agent in ducks. Sequence analysis revealed secondary structures that were shared with HDV, including self-complementarity and ribozyme features. The predicted viral protein shares 32% amino acid similarity to the small delta antigen of HDV and comprises a divergent phylogenetic lineage. The discovery of an avian HDV-like agent has important implications for the understanding of the origins of HDV and sub-viral agents.

Sign in / Sign up

Export Citation Format

Share Document