Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2012 Feb 16;13(3):214-22.
doi: 10.1038/ni.2229.

Intrinsic antiviral immunity

Nan Yan  1 , Zhijian J Chen
Affiliations
Review

Intrinsic antiviral immunity

Nan Yan et al. Nat Immunol. .

Abstract

Intrinsic antiviral immunity refers to a form of innate immunity that directly restricts viral replication and assembly, thereby rendering a cell nonpermissive to a specific class or species of viruses. Intrinsic immunity is conferred by restriction factors that are mostly preexistent in certain cell types, although these factors can be further induced by viral infection. Intrinsic virus-restriction factors recognize specific viral components, but unlike other pattern-recognition receptors that inhibit viral infection indirectly by inducing interferons and other antiviral molecules, intrinsic antiviral factors block viral replication immediately and directly. This review focuses on recent advances in understanding of the roles of intrinsic antiviral factors that restrict infection by human immunodeficiency virus and influenza virus.

PubMed Disclaimer

Figures

Figure 1
Figure 1. Evolution of innate immunity
A diagram illustrating the evolutionary progression from `RNA-based' immunity in plant and invertebrate cells (a) to `Protein-based' immunity in vertebrate cells (b). In `RNA-based' immunity, incoming viral RNA is processed by Dicer into small RNAs that directly target the virus through RISC-mediated RNAi. In `Protein-based' immunity, incoming viral RNA is recognized by PRRs that signals to activate IFN expression, which then activates the expression of many interferon-stimulated genes (ISGs) to inhibit viral replication. Some of the ISGs are intrinsic antiviral factors that are constitutively present in certain cell types and can block viral replication immediately and directly.
Figure 2
Figure 2. Intrinsic antiviral factors against HIV-1
Many steps of the HIV-1 life cycle are targeted by intrinsic antiviral factors. HIV-1 has evolved strategies to counteract these intrinsic antiviral factors, through accessory proteins or other unknown mechanisms that are currently under investigation.
Figure 3
Figure 3. Intrinsic antiviral factors against influenza virus
A diagram of influenza virus life cycle and known intrinsic antiviral factors against influenza virus.
See this image and copyright information in PMC

References

    1. Hamilton AJ, Baulcombe DC. A species of small antisense RNA in posttranscriptional gene silencing in plants. Science. 1999;286:950–952. - PubMed
    1. Zamore PD, Tuschl T, Sharp PA, Bartel DP. RNAi: double-stranded RNA directs the ATP-dependent cleavage of mRNA at 21 to 23 nucleotide intervals. Cell. 2000;101:25–33. - PubMed
    1. Aoki K, Moriguchi H, Yoshioka T, Okawa K, Tabara H. In vitro analyses of the production and activity of secondary small interfering RNAs in C. elegans. EMBO J. 2007;26:5007–5019. - PMC - PubMed
    1. Diaz-Pendon JA, Li F, Li WX, Ding SW. Suppression of antiviral silencing by cucumber mosaic virus 2b protein in Arabidopsis is associated with drastically reduced accumulation of three classes of viral small interfering RNAs. Plant Cell. 2007;19:2053–2063. - PMC - PubMed
    1. Umbach JL, Cullen BR. The role of RNAi and microRNAs in animal virus replication and antiviral immunity. Genes & development. 2009;23:1151–1164. - PMC - PubMed

Publication types