Hepatitis Delta Virus
Introduction
Hepatitis delta virus or HDV was discovered in patients with a more severe
form of human hepatitis B virus (HBV) infection
HDV is often called a virus but strictly speaking, it does not satisfy the
definition of a virus and should be called subviral.
Morphology and structural features
HDV is a small, spherical RNA virus measuring 36 nm in diameter with an
inner nucleocapsid that consists of a short single-stranded, circular RNA
and approximately molecules of hepatitis D antigen (HDAg)
The outer coat of the HDV virion consists of components taken from HBV,
thus mandating a coinfection process with HBV
The envelope of HDV particles contains the HDV surface antigen
(HBsAg), which includes the small, medium, and large HbsAg
Characteristics and life cycle
This pathogen replicates in the liver and frequently causes fulminant
hepatitis
Hepatitis delta virus has also been associated with the development of liver
cancer.
The process of their invasion and proliferation takes place through
the following steps
First, the HDV virion binds to the human hepatocyte through an interaction
between the large HBsAg and the host receptor
Entry, the HDV genome is translocated to the nucleus via the HDAg
Upon arriving in the nucleus, HDV commandeers host RNA polymerase II,
a DNA-directed RNA polymerase, for transcription of HDV RNA.
Replication of the HDV occurs through a rolling-circle mechanism
The next step is the synthesis of multimeric linear transcripts from the
circular genomic template
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Introduction
Hepatitis delta virus or HDV was discovered in patients with a more severe
form of human hepatitis B virus (HBV) infection
HDV is often called a virus but strictly speaking, it does not satisfy the
definition of a virus and should be called subviral.
Morphology and structural features
HDV is a small, spherical RNA virus measuring 36 nm in diameter with an
inner nucleocapsid that consists of a short single-stranded, circular RNA
and approximately molecules of hepatitis D antigen (HDAg)
The outer coat of the HDV virion consists of components taken from HBV,
thus mandating a coinfection process with HBV
The envelope of HDV particles contains the HDV surface antigen
(HBsAg), which includes the small, medium, and large HbsAg
Characteristics and life cycle
This pathogen replicates in the liver and frequently causes fulminant
hepatitis
Hepatitis delta virus has also been associated with the development of liver
cancer.
The process of their invasion and proliferation takes place through
the following steps
First, the HDV virion binds to the human hepatocyte through an interaction
between the large HBsAg and the host receptor
Entry, the HDV genome is translocated to the nucleus via the HDAg
Upon arriving in the nucleus, HDV commandeers host RNA polymerase II,
a DNA-directed RNA polymerase, for transcription of HDV RNA.
Replication of the HDV occurs through a rolling-circle mechanism
The next step is the synthesis of multimeric linear transcripts from the
circular genomic template
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