Immune Netw.  2013 Oct;13(5):168-176. 10.4110/in.2013.13.5.168.

The Natural Killer Cell Response to HCV Infection

• Ahlenstiel G

• KMID: 1493610
• DOI: http://doi.org/10.4110/in.2013.13.5.168

Abstract

In the last few years major progress has been made in better understanding the role of natural killer (NK) cells in hepatitis C virus (HCV) infection. This includes multiple pathways by which HCV impairs or limits NK cells activation. Based on current genetic and functional data, a picture is emerging where only a rapid and strong NK cell response early on during infection which results in strong T cell responses and possible subsequent clearance, whereas chronic HCV infection is associated with dysfunctional or biased NK cells phenotypes. The hallmark of this NK cell dysfunction is persistent activation promoting ongoing hepatitis and hepatocyte damage, while being unable to clear HCV due to impaired IFN-gamma responses. Furthermore, some data suggests certain chronically activated subsets that are NKp46high may be particularly active against hepatic stellate cells, a key player in hepatic fibrogenesis. Finally, the role of NK cells during HCV therapy, HCV recurrence after liver transplant and hepatocellular carcinoma are discussed.

Keyword

Natural killer cell; Hepatitis C virus; Viral hepatitis; Chronic infection

MeSH Terms

Bias (Epidemiology)
Carcinoma, Hepatocellular
Hepacivirus
Hepatic Stellate Cells
Hepatitis
Hepatocytes
Killer Cells, Natural*
Liver
Phenotype
Recurrence
Transplants

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