HBcAg

Last updated
Capsid protein
Identifiers
Organism Hepatitis B virus genotype B2 (isolate Vietnam/9873/1997)
SymbolC
UniProt Q9QAB9
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Structures Swiss-model
Domains InterPro
Hepatitis core antigen
Identifiers
SymbolHepatitis_core
Pfam PF00906
InterPro IPR002006
CATH 7abl
SCOP2 7abl / SCOPe / SUPFAM
Available protein structures:
Pfam   structures / ECOD  
PDB RCSB PDB; PDBe; PDBj
PDBsum structure summary
Schematic overview of the hepatitis B virus particle. HBcAg is a constituent of the nucleocapsid core (green hexagon). HBV.png
Schematic overview of the hepatitis B virus particle. HBcAg is a constituent of the nucleocapsid core (green hexagon).
The genome organisation of HBV. Some genes overlap. (ORF Core, at bottom left, encodes HBcAg. HBV Genome.svg
The genome organisation of HBV. Some genes overlap. (ORF Core, at bottom left, encodes HBcAg.

HBcAg (core antigen) is a hepatitis B viral protein. [1] [2] It is an indicator of active viral replication; this means the person infected with Hepatitis B can likely transmit the virus on to another person (i.e. the person is infectious).

Contents

Structure and function

HBcAg is an antigen that can be found on the surface of the nucleocapsid core (the inner most layer of the hepatitis B virus). While both HBcAg and HBeAg are made from the same open reading frame, HBcAg is not secreted. HBcAg is considered "particulate" and it does not circulate in the blood but recent study show it can be detected in serum by Radioimmunoassay. However, it is readily detected in hepatocytes after biopsy. When both HBcAg and HBeAg proteins are present, it acts as a marker of viral replication, and antibodies to these antigens indicates declining replication.

Interactions

Tapasin can interact with HBcAg18-27 and enhance cytotoxic T-lymphocyte response against HBV. [3]

See also

Related Research Articles

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References

  1. Kimura T, Rokuhara A, Matsumoto A, et al. (May 2003). "New enzyme immunoassay for detection of hepatitis B virus core antigen (HBcAg) and relation between levels of HBcAg and HBV DNA". J. Clin. Microbiol. 41 (5): 1901–6. doi:10.1128/JCM.41.5.1901-1906.2003. PMC   154683 . PMID   12734224.
  2. Cao T, Meuleman P, Desombere I, Sällberg M, Leroux-Roels G (December 2001). "In vivo inhibition of anti-hepatitis B virus core antigen (HBcAg) immunoglobulin G production by HBcAg-specific CD4(+) Th1-type T-cell clones in a hu-PBL-NOD/SCID mouse model". J. Virol. 75 (23): 11449–56. doi:10.1128/JVI.75.23.11449-11456.2001. PMC   114731 . PMID   11689626.
  3. Chen X (May 2014). "Tapasin modification on the intracellular epitope HBcAg18-27 enhances HBV-specific CTL immune response and inhibits hepatitis B virus replication in vivo". Lab. Invest. 94 (5): 478–90. doi: 10.1038/labinvest.2014.6 . PMID   24614195.