Interferon-stimulated genes (ISGs) (ISGs)

Interferon-stimulated genes (ISGs) are a vast collection of genes—numbering in the hundreds—that are transcriptionally activated in response to interferon (IFN) signaling through the JAK-STAT pathway (Schoggins JW, Annu Rev Virol, 2019). These genes encode proteins that collectively establish an antiviral state within cells, inhibiting viral replication at multiple stages, from entry to egress (Schneider WM, et al., Annu Rev Immunol, 2014). Beyond viral defense, ISGs play pivotal roles in regulating cell proliferation, apoptosis, and the activation of the innate and adaptive immune systems. In clinical settings, the term interferon efficacy-related genes often refers to specific subsets of ISGs used as biomarkers to predict or monitor the response to interferon-based therapies in chronic viral infections like Hepatitis C or autoimmune disorders like Multiple Sclerosis (Messmer MN, et al., Front Immunol, 2021). An elevated interferon signature is also a hallmark of certain autoimmune diseases, such as Systemic Lupus Erythematosus (SLE), where it serves as a marker of disease activity and a potential target for pathway-modulating drugs like JAK inhibitors or anti-IFN antibodies (Crow YJ, et al., Nat Rev Immunol, 2015). Because this term refers to a broad functional group of genes rather than a single molecular entity, it is typically utilized for patient stratification and pharmacodynamic monitoring rather than as a singular therapeutic target.

Other names

Interferon efficacy-related genesInterferon-responsive genesInterferon-regulated genesType I interferon signatureInterferon-stimulated gene signature

Drugs targeting the interferon pathway either mimic natural interferons to induce these genes (agonists like Peginterferon) or inhibit the signaling cascade (antagonists like Anifrolumab or JAK inhibitors) to prevent their over-expression in inflammatory states.