IFN-λ: Novel Antiviral Cytokines

Abstract

The first line of defense against viral infections is mediated by interferons (IFN)s, which are produced rapidly by the infected host. Type I IFNs (IFN-alpha/beta) are known to combat viruses both directly by inhibiting viral replication in the cells and indirectly by stimulating the innate and adaptive immune responses. Recently, a novel class of cytokines was discovered and named IFN-lambda (alternatively type III IFN or interleukin-28/29 [IL- 28/29]), based on IFN-like antiviral activity and induction of typical IFN-inducible genes. Here, we review the literature on IFN-lambda and discuss the current knowledge of the functions and mechanisms of action of IFN-lambda.

Immunobiology of Japanese Encephalitis Virus

“…In addition to their antiviral activity, type I IFNs are key to efficient establishment of the adaptive immune responses (Borden et al, 2007). Type III IFNs (IFN-1, -2 and -3) are new members of the IFN superfamily first discovered in 2003 and shown to be related to type I IFN (Ank et al, 2006). However, they differ by signalling through a receptor complex that is different from that used by type I IFNs.…”

IL-27, a Cytokine, and IFN-λ1, a Type III IFN, Are Coordinated To Regulate Virus Replication through Type I IFN

“…Although IFN-l binds to distinct receptors, IL-28R1 and IL-10Rb (24), it activates signal transduction pathways by a manner similar to that activated by type I IFN (23,24) through inducing tyrosine phosphorylation of STAT proteins (27). IFN-l also shows antiviral abilities, similar to those of type I IFN (28), by inhibiting the replication of a number of viruses, including HCV, hepatitis B virus (HBV), encephalomyocarditis virus, IAV, and vesicular stomatitis virus (23,24,(28)(29)(30)(31).…”

Inhibition of type I and type III interferons by a secreted glycoprotein from Yaba-like disease virus

“…Type I and type III IFNs are produced in response to viral infections (3,4,8,9). Binding of IFNs to their corresponding cellular receptor complexes, despite their differences, induces similar signaling events of the Janus kinase (JAK)-signal transducers and activators of transcription (STAT) signal transduction pathway, including phosphorylation of kinases Jak1 and Tyk2 and activation of latent transcriptional factors STAT1 and STAT2 as well as STAT3, STAT4, and STAT5 to a lesser extent (3,4,6,10).…”

“…Activated STATs regulate gene expression, and both types of IFNs induce very similar sets of genes, including many genes that encode important mediators of antiviral response (11,12). Consequently, type III and type I IFNs are both able to induce an antiviral state in cells (3,8). However, whereas type I IFN receptors are expressed in most cell types, IFN-R1 demonstrates a more restricted pattern of expression, limiting the response to type III IFNs to primarily epithelium-like tissues (13).…”