The immunologic basis for hepatitis C infection

Jiaren Sun, Kui Li, Mohamed Tarek Shata, Teh Sheng Chan

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

Purpose of review: The host immune system is arguably involved in nearly every step of hepatitis C virus (HCV) infection. In patients, the outcome, whether it is a natural infection or results from an interferon-α-based treatment, is determined by a series of complex host-virus interactions. In this review, we focus on the state of research addressing the immune mechanisms critical for viral clearance and disease resolution. Additional discussion is devoted to the evasion and blockade tactics of HCV as well as to current efforts aimed at disrupting the replication cycle of this well-evolved virus. Current theories of immune-mediated injury of hepatocytes are also discussed. Recent findings: Strong and persistent CD8 + and CD4 + T-cell responses are critical in HCV clearance. Although each may play a unique role in the process, the intrahepatic interferon (IFN)-γ produced by these cells is central to their antiviral action. IFN-α/β alone, without triggering subsequent HCV-specific T-cell responses, may not lead to a sustained viral response in vivo. Synergism among several immune cells, including T, NK, and NKT cells is important for disease resolution. Additional data raise the possibility that viral clearance and liver injury are mediated through different effector mechanisms of T cells. HCV employs evasion and sabotage tactics to escape from the host's immune system. HCV NS3/4A serine protease can block viral activation of a key transcription factor in initiating cellular IFN response. A newly identified NS3 protease inhibitor can result in a reduction of viremia, illustrating the potential of the viral-enzyme-targeted drug in patients. Summary: Current data provide a rationale to further explore immune augmentation as a therapeutic intervention in HCV infection.

Original languageEnglish (US)
Pages (from-to)598-602
Number of pages5
JournalCurrent Opinion in Gastroenterology
Volume20
Issue number6
DOIs
StatePublished - Nov 2004

Fingerprint

Hepatitis C
Hepacivirus
Interferons
Infection
Virus Diseases
T-Lymphocytes
Immune System
Viruses
Virus Activation
Natural Killer T-Cells
Viremia
Wounds and Injuries
Serine Proteases
Protease Inhibitors
Natural Killer Cells
Antiviral Agents
Hepatocytes
Transcription Factors
Liver
Enzymes

Keywords

  • Cytotoxic T lymphocytes
  • Hepatitis C virus
  • Immune responses
  • Liver
  • Viral hepatitis

ASJC Scopus subject areas

  • Gastroenterology

Cite this

The immunologic basis for hepatitis C infection. / Sun, Jiaren; Li, Kui; Shata, Mohamed Tarek; Chan, Teh Sheng.

In: Current Opinion in Gastroenterology, Vol. 20, No. 6, 11.2004, p. 598-602.

Research output: Contribution to journalArticle

Sun, Jiaren ; Li, Kui ; Shata, Mohamed Tarek ; Chan, Teh Sheng. / The immunologic basis for hepatitis C infection. In: Current Opinion in Gastroenterology. 2004 ; Vol. 20, No. 6. pp. 598-602.
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