Interferon-λs: the modulators of antivirus, antitumor, and immune responses

IFN-lambda s, including IFN-lambda 1, IFN-lambda 2, and IFN-lambda 3, also known as IL-29, IL-28A, or IL-28B, are a newly described group of cytokines distantly related to the type I IFNs and IL-10 family members. The IFN-lambda R complex consists of a unique ligand-binding chain, IFN-lambda R1 (also designated IL-28R alpha), and an accessory chain, IL-10R2, which is shared with receptors for IL-10-related cytokines. IFN-lambda s signal through the IFN-lambda R and activate pathways of JAK-STATs and MAPKs to induce antiviral, antiproliferative, antitumor, and immune responses. In this review, we summarize recent findings about the biology of IFN-lambda s and their pathophysiological roles in viral infection, cancer, and immune responses of the innate and adaptive arms. J. Leukoc. Biol. 86: 23-32; 2009.