Interferon response pathway

The interferon response pathway is a complex cellular signaling network activated primarily by infection with viruses and other pathogens. It is not a single molecule or receptor but rather encompasses multiple classes of interferons—Type I (e.g., IFN-alpha, IFN-beta), Type II (IFN-gamma), and Type III (IFN-lambda)—and their respective cell surface receptors. Upon recognition of pathogen-associated molecular patterns by pattern recognition receptors like toll-like receptors or RIG-I/MDA5, cells secrete interferons that bind to their cognate heterodimeric receptor complexes on target cells. This binding activates associated Janus kinases (JAKs) and leads to phosphorylation and activation of STAT transcription factors. The resulting transcriptional complexes induce expression of hundreds of interferon-stimulated genes (ISGs) that mediate antiviral responses, enhance antigen presentation via upregulation of MHC class I/II molecules, modulate cell proliferation/apoptosis, suppress angiogenesis in tumors, and coordinate broader immune responses. Therapeutically relevant drugs include recombinant forms of various interferons used for viral infections and some cancers; however, these drugs act on specific proteins within this broader signaling cascade rather than "the interferon response pathway" as a whole. Note: "Interferon response pathway" refers to an entire biological process/signaling network—not a discrete therapeutic target such as a receptor or enzyme. For structured data purposes it should be flagged as incorrect if used where an individual molecular target is required. Key points supporting this assessment: The pleiotropic biological activities...are initiated by binding...of heterodimeric receptor complexes...Each receptor heterodimer consists...for their cognate IFNs... Interferons are classified into three types according to different receptors... The 'interferon response' involves many downstream effectors including JAKs/STATs...

Other names

IFN signaling pathwayInterferon signaling cascadeIFN pathwayType I/II/III interferon pathways