Type I interferon (IFN-I)

Type I interferons are a family of cytokines primarily comprised of multiple IFN-α subtypes, IFN-β, IFN-ε, IFN-κ, and IFN-ω in humans; these are encoded by genes clustered on chromosome 9p21.3[6]. All type I interferons bind to a shared receptor complex known as the type I interferon receptor (IFNAR), which includes two subunits: IFNAR1 and IFNAR2[6][1][5]. Upon ligand binding, the receptor-associated kinases JAK1 and TYK2 are activated, leading to phosphorylation of STAT1 and STAT2, formation of the ISGF3 transcription complex, and induction of hundreds of interferon-stimulated genes[5][3]. Type I interferons play fundamental roles in the immune system, particularly in antiviral defense, immunosuppression, tumor surveillance, and the regulation of innate and adaptive immune responses[6][5][1]. Clinically, recombinant type I interferons are used to treat diseases such as chronic viral hepatitis, multiple sclerosis, and certain hematologic and solid cancers; their use is limited by flu-like and neuropsychiatric side effects and the risk of autoimmune activation[1][5].

Other names

Interferon type IIFN type IIFN-α/βIFN-αIFN-βIFN-ɛIFN-κIFN-ω

Activation of the JAK-STAT signaling pathway via the type I interferon receptor (IFNAR1/IFNAR2), leading to induction of interferon-stimulated genes and antiviral, antiproliferative, and immunomodulatory effects[1][5][3][7] Inhibition of viral protein synthesis by inactivation of eukaryotic translation initiation factor 2α (eIF-2α)[1] Activation of RNase L, leading to degradation of viral RNA[1]