IFNL3

interferon lambda 3

IL-28 belongs to the IFN lambda family, a novel family of cytokines within the IL-10 superfamily. The three members of this family are IL-29 (IFN lambda 1), IL-28A (IFN lambda 2), and IL-28B (IFN lambda 3), and are also known as the type III Interferons. An active IL-29 gene is absent in mice, and sequence homology between mouse IL-28A and B is 97%. Expression of these cytokines has been observed in a wide variety of cells in response to viral infection and in response to TLR3 or TLR9 ligands. The IFN lambda family signals through a heterodimeric receptor of which one subunit, IL-10R2, is shared with other members of the superfamily. The second subunit, IFN lambda R1 or IL-28R alpha, is unique to the IFN lambdas. Signaling occurs through the Jak/STAT pathway in a similar manner to signaling by the type I IFNs (IFN alpha/beta) and activates many of the same genes despite low sequence homology between the cytokines and receptors in the two families. Both IFN families display antiviral, antitumor, and antiproliferative effects, making the IFN lambdas potential alternatives to IFN-alpha for anticancer and antiviral therapies. Unlike the type I IFNs, which are able to stimulate most cells, response to IFN lambda stimulation appears to be limited to dendritic, epithelial, and some tumor cells. Another notable difference is the ability of the IFN lambda stimulation to drive dendritic cells towards the production of CD4+CD25+FoxP3+ regulatory T-cells, suggesting a possible immunoregulatory role.;